Assessing community attitudes toward medical practitioner authority Ken Rigby and Jacques C. Metzer University of South Australia, Adelaide Abstract:Despite the widespread belief that medical authority is under increasing challenge, no adequate research instrument has been available to measure relevant community attitudes. This paper reports the development of the Attitude Toward Medical Practitioners Scale (the AMPS). Samples of Australians (in total N > 1000) completed the AMPS, using three different procedures. The reliability of the scale, assessed by coefficient alpha, ranged from 0.80 to 0.86. A principal component analysis of the AMPS yielded loadings on each item exceeding 0.3 on the first unrotated factor; subsequent varimax rotation revealed dimensions associated with critical attitudes to doctors and evaluations of doctors' interpersonal competence and technical expertise. Positive and significant correlations between the AMPS and one measure of the General Attitude toward Institutional Authority (GAIAS) strongly suggested that the scale is consistent with generalised evaluations of community authorities. The specific validity of the AMPS was supported for each of three samples, using as validating criteria respondent ratings of the last doctor visited, satisfaction with the consultation and reported compliance with the doctor's advice. Significant improvements were found in the prediction of each of these criteria by the addition of the AMPS to contributions made by the GAIAS and the demographic variables, age and sex. The AMPS is an appropriate measure for assessing community attitudes towards medical practitioners conceived as institutional authorities, at least in the Australian context. ( A w t J Public Health 1992; 16: 403-12) t is generally assumed that the authority of medical practitioners is increasingly under challenge. Haug and Lavin, for instance, have noted that views expressed in the popular media have generally supported the existence of such a trend, as also have those of physicians and academics,' yet there is a paucity of research instruments suitable for assessment of relevant community attitudes. It is not known to what extent attitudes towards medical practitioners are, in fact, critical or challenging, from which sections of the community they are more (or less) pronounced and whether any trend in such attitudes is continuing. Despite a widespread readiness to assume a crisis in public confidence in doctors, until an acceptable measure of respect for practitioner authority has been developed, the matter cannot be examined adequately. Currently one may identify three different approaches to the assessment of attitudes to medical practitioners, each having claims for consideration. These comprise, firstly, patient satisfaction scales; secondly, health locus-of-control measures; and thirdly, tests of acceptance or rejection of medical authority. None of these approaches has so far yielded a measure suitable for assessing levels of community respect for medical practitioners. Patient satisfaction with medical care has, in recent years, received considerable attention, resulting in the development of a number of psychometrically adequate measures.4-6These and others have been ably reviewed by Zastowny et al and by Patrick et al.7.n
I
Correspondence to Dr K Rigby, School of Social Studies, University of South Australia, Adelaide, SA 5000
Such measures are typically multifaceted, covering a wide range of factors that may be expected to give rise to satisfaction or dissatisfaction with the services provided by doctors. They characteristically include the means of appraising the doctor's conduct, especially in relation to perceived technical competence and interpersonal care,g but also go beyond these. As Patrick et al have shown, such scales are typically and appropriately concerned with matters like the accessibility or convenience of getting an appointment, the mechanism of payment and the availability of doctorss Such scales do not tell us how people feel about doctors themselves. Indeed, a strong feeling that doctors are 'not available enough' might well reflect a positive attitude towards doctors. The development of measures for beliefs about the determinants of a person's health also relates to the question of doctor evaluation. Based upon Rotter's concept of internal and external locus of contro1,'O a number of scales dealing exclusively with health have been developed."J2 Locus of control refers to an expectations people have about ,whether they can effectively control outcomes; if they believe they can, they have an internal locus of control; if they believe outcomes are controlled by others, they have an external locus of control. It may be surmised that patients who have an external rather than an internal locus of control for health outcomes would value doctors relatively highly and accept their authority. Any challenge to medical authority, it seems, would be more likely to come from patients with an internal rather than an external locus of control. However, Lau and Ware's research
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employing a health-specific locus of control measure, controlling for acquiescence set, has shown that belief in personal (internal locus) control and belief in provider (external locus) control were unexpectedly positively and significantly correlated.l 2 The assumption that there is a polarity of internal and external attributions with respect to health was clearly not supported. One cannot therefore infer a challenge to medical authority from a patient with a relatively internal health locus of control if such a person is, in fact, also likely to have a relatively high external health locus of control. Nevertheless, some aspect or factor of a healthspecific locus of control measure may be relevant to the task of assessing community attitudes towards medical practitioners. A possible candidate is the provider-control subscale of the health-specific locus of control measure proposed by Lau and Ware.” This eight-item scale consists of a set of items intended to tap the belief that doctors are effective in helping their patients. It does, however, have some important shortcomings. Despite its narrow range of item content, the internal consistency or reliability of the measure is quite low (a= 0.67). Also its limitation in scope must count against it. It is reasonable to suppose that evaluative reactions towards doctors embrace a much wider range of issues (some of which are included in patient satisfaction scales) than are covered by measures which focus only on the doctor’s perceived helpfulness, important though that must be. In addition, locus of control measures are basically concerned with cognitive aspects of attitudes. Affective or emotional aspects of attitudes towards doctors are at least equally important, as Wolf, Putnam, James and Stiles correctly assumed in constructing their measure of ‘patient’s perception of physician’s behaviour’.IY A further approach to gauging public attitudes towards doctors involves assessing in a relatively direct manner the extent to which people are predisposed to accept or reject medical authority. This approach has much to commend it, since it is unambiguously concerned with evaluation of doctors themselves, whether they are seen as trustworthy, deserving of respect, or alternatively not trustworthy and needing to be challenged. Haug and Lavin pioneered such an approach in their construction of a scale to assess ‘willingness to challenge MD authority’. Unfortunately, that measure was closely modelled upon the California F ScaleI5and as such, made certain questionable assumptions about the nature of attitudes to authority. The Haug and Lavin Scale consists of four forcedchoice items. In each case one may choose the ‘authoritarian-submissive’alternative, for example: ‘Every person should have complete faith in doctors and do what they tell you to do without a lot of questions’ or the corresponding ‘non-authoritarian’ alternative: ‘It’s alright for people to raise questions with doctors about anything they tell you to do’. According to the rationale underlying the F Scale and its derivative formulated by Haug and Lavin, acceptance of authority is part of an authoritarian syndrome which characterises a deeply prejudiced, 404
rigid, repressed and socially undesirable personality. This view has been trenchantly criti~ised’~*’’ and the F Scale itself has been shown to have highly dubious external validity.’&-‘OIt seems likely that the Haug and Lavin Scale is based upon a false dichotomy: that either one challenges medical authority or one is submissively authoritarian. Alternative models for assessing attitudes to authority, with no such built-in assumptions about psychopathology, offer greater promise for the development of an appropriate A recently published scale in this area, the General Attitude towards Institutional Authority Scale (GAIAS) is composed of four significantly intercorrelated subscales, assessing attitudes towards various institutional authorities, namely the police, the army, the law and teachers.“ The GAIAS has avoided assumptions of psychopathologyand irrationality on the part of either supporters or opponents of institutional authorities. Correlations with measures of I Q and self-acceptance have been non~ignificant.‘~.’~ The generality and behavioural validity of the measure has been confirmed in a variety of population^.'^-^^ Since medical practitioners undoubtedly constitute an institutional authority, it was proposed that an appropriate attitude towards medical practitioners scale (or AMPS) should be constructed along lines followed in the construction of the subscales of the GAIAS, but with medical practitioners as the target. This approach involves initially collecting a large number of statements which are judged to imply, quite unambiguously, respect or disrespect for the medical practitioner. Item content may be derived from judgments made in a variety of areas, such as the doctor’s competence, capacity to care and general character. The final arbiter of item-relevance is determined by the capacity of items to show relatively high levels of interrelationship. Although the initial choice of items with this method tends to be intuitive and not theoretical (compared, for instance, with that of locus of control measures), there is good reason to suppose that this method yields measures which not only have enough psychometric properties, but also predict relevant behaviour.YO The qualities required of the proposed scale were: 1. The items should be unambiguously relevant to the issue of respect or disrespect for the authority of doctors; in short, the scale should have face-validity. 2. The scale should contain items which correlate significantly with the scale total, should be balanced to control for acquiescence set, and should show a satisfactory level of internal consistency, as assessed by coefficient alpha. 3. The scale should correlate significantly and positively with other measures of attitude towards institutional authorities, such as the GAIAS and its subscales. This follows from the assumption of a general attitude to authority, which has been confirmed in series of studies with diverse
population^.^^^^^^^ 4.
The scale should yield evidence of concurrent validity based upon criteria clearly relevant to
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positive and negative reactions towards particular medical practitioners. 5. Finally, the AMPS should show greater validity than an alternative, more general measure of attitude to authority, such as the GAIAS, that is, a degree of specific validity should be demonstrated. To establish concurrent validity for the AMPS, one may draw upon the respondents’ reactions towards the last doctor they visited how positively or negatively the doctor was evaluated, and to what extent the doctor’s advice was complied with. Both kinds of criteria are important: the former, since positive ratings would clearly be expected of respondents with a generally high level of respect for medical practitioners, and the latter, since behavioural compliance is especially relevant to the question of acceptance of medical authority. Whilst doing what a doctor says may on occasions result from a doctor being manipulated by a patient to say what the patient wants to hear, it is reasonable to suppose that for the most part the compliant patient is responding positively to a medical authority whom he or she respects. There are problems of assessing compliance, especially outside the hospital setting where one may be forced to rely upon self-report data for which the reliability may be questioned. Highly accurate information on compliance using such an approach may be difficult to achieve. Nevertheless, there is evidence that self-reported ratings of frequencies of compliant and non-compliant behaviours do correlate significantly with corresponding peer-reported ratings, at least under conditions in which the information is provided anonymously so that any tendency to give the socially desirable response is reduced.Y0 A further issue of relevance to the proposed validating scheme concerns the extent to which attitudes and behaviour may be expected to correlate. Following the trail of La Piere$’ and later Wicker,Y2it became fashionable to dismiss the possibility of all but the weakest connections between attitudes and behaviour. Clearly there are substantial and often countervailing situational influences that would tend to weaken any relationship. However, more recent research into the conditions governing attitude/ behaviour consistency has encouraged the belief that where correspondence between an attitudinal and a behavioural measure exists, a real relationship may be f o ~ n d With . ~ ~a ~ single ~ ~ behavioural index, as opposed to a multiple index, the relationship of behaviour to attitude is likely to be comparatively small, yet significant. It follows that a measure of attitudes to medical practitioners should yield small but significant correlations with measures of appropriately corresponding behavior, such as reported compliance with a doctor’s advice given on a particular occasion. I n o b t a i n i n g d a t a f o r this study t w o methodological considerations were considered important: first, to sample among different subpopulations, where possible drawing upon a wide cross-section of respondents, and second, to employ different methods of data collection to demonstrate
that the obtained results did not depend on a particular research method. Students from Australian universities formed one type of respondent; members of the general population of Adelaide, South Australia, the other. Data collection techniques included mass administered questionnaires, individual interviews and a postal survey. Because people are more likely to respond in a socially desirable manner when they are talking to another person, compared with responding privately to a questionnaire item, one might reasonably assume that there were variations between samples because degree of anonymity varied. Analyses of results for subsamples using different respondent types and data collection methods were carried out separately. In this way it was hoped that obtaining results that were consistent across samples would confirm the robust nature of the scale. In summary, it was proposed to develop a scale for the assessment of community attitudes towards medical practitioners that was especially relevant to the question of community respect for their authority. The validity the AMPS was to be investigated by correlation with validating criteria derived from ratings of the last doctor visited and reported compliance with that doctor’s advice. Higher correlations were predicted with these validating criteria than with those obtained using the GAIAS. Replications were intended using different types of respondents (students and non-students) and employing a variety of data gathering procedures.
Methods Initially 40 items, consisting of equal numbers of favourable and unfavourable statements about medical practitioners, were assembled. Some related to the professional competence of doctors, others to more personal of general qualities. Each statement was phrased in such a way that agreement or disagreement with it would indicate a comparatively positive or negative attitude towards doctors in general. For example, agreeing with: ‘doctors generally know what is best for their patients’ implied a positive attitude to the practitioner, ‘a lot of doctors are more interested in money than in helping people’ a negative attitude. Using a Likert format in which scores for each item were summated, high scorers were expected to show favourable and very respectful attitudes toward medical practitioners, low scorers, unfavourable and disrespectful ones. The items were presented as statements that had been made about medical practitioners, and respondents were invited to give their reactions to each of them. The instructions were: write 1 if you agree strongly, 2 if you agree, 3 if you are neutral or uncertain, 4 if you disagree, and 5 if you disagree strongly. The questionnaire was administered to 100 nonstudent respondents who were personally contacted and asked to complete the 40-item questionnaire. The scale proved to be highly reliable, with a Cronbach alpha coefficient of 0.95. It appeared feasible to reduce the length of the scale to 16 items and still preserve adequate reliability. Two versions, Scale A and Scale B, were devised using the items with the
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highest item-total correlations consistent with providing equal numbers of positively and negatively keyed items. Scale A was chosen for use in the major study in which cross-validation would occur. The initial alpha coefficient for Scale A was 0.89; the correlation between the positively and negatively keyed halves (after appropriate item score reversals) was 0.79 (P < 0.001). In the major study reported in this paper, the proposed AMPS was presented with its 16 items interspersed with those comprising the short version of the GAIAS.” This scale also consists of 16 items and has 4 balanced subscales with items tapping attitudes toward the army, the law, teachers and the police. Therefore a 32-item scale was assembled, employing the same format and instructions as those used in the pilot study. The combined AMPS and GAIAS were included in a questionnaire which sought additional information. Respondents were asked to rate the last doctor they saw in terms of each of the following qualities: 1. ability to listen to you, 2. ability to find out what’s wrong, 3. conscientiousness, 4. concern for you as a person, 5. deservingness of respect as a medical doctor, 6. personal warmth, and 7. ability to communicate effectively. A five-point scale was provided for each criterion: 1 very low; 2 fairly low; 3 moderate extent; 4 fairly high, and 5 very high. To assess general satisfaction with the last consultation, respondents were asked to indicate: 1 for extremely dissatisfied, 2 for rather dissatisfied, 3 for moderately satisfied, and 4 for highly satisfied. Compliance was assessed by asking respondents to indicate the extent to which they followed the last doctor’s advice: 1 for not at all, 2 a small extent, 3 about half, 4 to a large extent, and 5 completely. To obtain demographic data, questions were included to provide age, occupation and sex. Respondents’ names were not required. Three samples of respondents were used, each providing information following a different procedure. Sample 1 consisted of first year university students attending classes in the School of Social Studies at the University of South Australia in the cities of Adelaide and Whyalla, and students attending the Northern Territory University in the Northern Territory of Australia. Questionnaires were administered to these respondents in groups. The remaining respondents were nonstudents. One group was contacted by social work students who were each asked, as part of a research assignment, to contact three nonstudents, where possible choosing individuals who differed in occupational status. Occupational status was defined operationally according to the Congalton Scale, a comprehensive list of occupations classified on a seven-point scale according to status values provided by a wide crosssection of the Australian public acting as raters.Y5For the purpose of this inquiry the classifications were collapsed into three categories: high (status 1 and 2), medium (status 3, 4 and 5), and low (status 6 and 7). Respondents were interviewed and while no names 406
were required, the degree of anonymity was obviously lower than in the first sample. Sample 3 was a stratified random sample contacted by l e t t e r . I n ‘an a t t e m p t t o maximise representativeness, names were randomly selected from the South Australian Electoral Roll. Equal numbers of respondents were chosen from Adelaide suburbs classified (according to the Adelaide socioeconomic atlas), as high, medium and low social status.36As the electoral rolls also contained stated occupations for each person listed, only people with occupations of a status (defined by the Congalton Scale) corresponding to their suburbs were selected to form the population from which the final sample of 1 000, half male and half female, was drawn. About one third of the persons to whom letters were sent returned completed questionnaires. Details of sex, age and social status are presented in Table 1 for each of the samples. No attempt was made to identify the social status of the student respondents. For a proportion of nonstudents, especially female respondents, information regarding occupation was not available, and they too were unclassified. From Table 1 it is apparent that, for the most part, the student sample consisted of ‘mature-age’ people, their mean age being about 30 years. The interviewed respondents were, on average, about four years older. The postal survey provided the oldest respondents, on average 44 years. Age variability, as indicated by standard deviations and ranges, was much more evident among the postal respondents. Respondents of the different social status groups were well represented in samples 2 and 3, especially the middle status category. The relatively large proportion of ‘unclassified’females resulted from many of them describing themselves as having ‘home duties’. Results The reliability of the AMPS was examined independently for each of the three samples. Cronbach’s alpha, a measure of overall inter-item consistency, and correlations between positively and negatively keyed halves of the scale are given in Table 2 for the AMPS and, for comparison, for the GAIAS, a measure that figured largely in subsequent analyses. Table 2 shows that upon cross-validation, the AMPS, with alpha coefficients ranging from 0.80 to 0.87, had adequate internal consistency, despite the expected shrinkage in alpha from the original 0.89. Correlations between differently keyed halves were all statistically significant (P < 0.001). This is an important point since it shows that controlling for acquiescence has not occurred, as it sometimes does in the development of unrelated subscales.J7 A detailed analysis of the relationship between each item and the total scale (corrected for the contribution of the item) is presented in Table 3. This shows that every item for each of the three samples correlated significantly with the sum of the remaining items. The validity of each of the items as a contributor to the AMPS was thus confirmed, with correlations ranging from 0.28 to 0.68.
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Table 1 : Age, sex and social status composition of samples
Mean
Age (years) Standard deviation
Range
High
Social status level % Middle Low
Not classified
~~
Sample 1 - students, group questionnaire Males In = 771 29.48 Females In = I931 30.12 Total In = 2701 29.94
8.25 9.44 9.1 1
16-53 16-54 16-54
0.0 0.0 0.0
Sample 2 - nonstudents, interviewed Males In = 1531 Females In = 236) Total In= 389)
35.01 32.34 33.96
9.96 8.63 9.54
18-73 20-64 18-73
33.5 24.2 29.8
39.8 48.4 43.2
25.8 22.9 24.7
0.8 4.6 2.3
Sample 3 - contacted by letter Males ( n = 156) Females In= 1901 Total In= 3461
45.52 42.08 43.63
17.26 16.14 17.72
17-90 17-79 17-90
20.5 4.7 11.9
48.1 52.7 50.6
24.4 13.7 18.5
7.1 28.9 19.1
In order to examine the internal structure of the AMPS, a principal components analysis of the 16-item scale was undertaken using results for the total set of 977 respondents, for whom a subsequent validation study was undertaken (See Table 6). This produced three factors with eigenvalues greater than one. In Table 4 factor loadings are given for each item; first, for Factor 1 in its unrotated form; and then for each of the three factors following varimax rotation. Factor 1 (unrotated) accounted for 33.1 per cent of the variance, each item being substantially loaded on it ( > 0.3). This result confirms the view that each of the items contributed effectively in the assessment of a coherent generalised tendency to evaluate medical practitioners positively or negatively. Varimax rotation enabled us to identify subfactors. The first factor is loaded substantially ( > 0.4) on items that express sentiments critical of doctors. This suggests that such feelings are particularly coherent regardless of their specific content. To some degree, however, this factor may be an artefact of balancing the scale to control for acquiescence set. As already noted, however, the two halves of the scale were positively correlated after reverse scoring, thus supporting the overall integrity of the scale. The second and third factors, accounting for 9.4 per cent and 6.6 per cent of the variance respectively, suggest a distinction between a dimension concerned with the personal helpfulness of doctors (‘a doctor is probably the best person to help with a personal problem’-loading of 0.74 on factor 2), and technical efficiency (‘treatments administered by doctors generally have a valid scientific basis’-loading of 0.65 on factor 3). It has already been noted that the
0.0 0.0 0.0
0.0 0.0 0.0
100.0 100.0 100.0
emergence of factors relating to interpersonal and technical aspects of medical care is commonly found with patient satisfaction scales. With the AMPS, however, they evidently account for a relatively small amount of the scale variance. In order to investigate the relationship between these last two dimensions, subscale scores were computed for sets of items loaded predominantly on one or other of these factors-the ‘personal helpfulness’subscale on items 5, 7, 9 and 14 and the ‘technical efficiency’ subscale on items 3, 6, 13 and 15. The two subscales were found to be moderately correlated (r = 0.46.975 df, P < 0.001). Despite some differentiation suggested by the factor analysis, the overall impression is of coherence. The most central item of the AMPS (as indicated by an unrotated factor loading of 0.74) was: ‘doctors deserve the high regard in which they are commonly held’. This item had loadings of > 0.3 on each one of the rotated factors. It may be taken as catching the essence of what was intended by the scale: a reliable measure of the extent to which members of the community feel respect for the medical profession as an institution. Before seeking to validate the AMPS, it was important to establish whether the extraneous variables for which data were available for each respondent, namely, age and sex, were related to scale scores and potentially capable of determining a significant relationship with validating criteria. Because data on the occupational status variable were missing, especially for the postal survey, this variable was not to be included in the analysis. In the event, correlations between occupational status and the AMPS were very low: for sample 2, r = -0.06, 378 df; for
Table 2: Internal consistency indices for the Attitude to Medical Practitioners Scale (AMPS) and the General Attitude towards Institutional Authority Scale (GAIAS) for three samples of respondents AMPS Sample Students lnterviewees Postal
GAIAS
Number
Alpha
‘pn”
Alpha
‘pn”
270 389 346
0.80 0.87 0.86
0.45 0.59
0.79 0.84 0.77
0.58 0.67 0.48
0.60
Note: la) ‘pn, the conelotion between positively and negatively keyed halves of o scale, wos calculated after appropriate item score reversals.
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Table 3: The Attitudes to Medical PractitionersScale (AMPS). Items for the AMPS with corrected item-total correlationsfor three samples of respondents.
-
Items
1
Students ( n = 270)
lnterviewees ( n = 389)
Postal ( n = 346)
Doctors generally know what is best for their patients Doctors have too much power in our society I R O I
0.46
0.65
0.61
0.52
0.57
0.58
3
It is wise to follow a doctor's directions very carefully
0.47
0.42
0.45
4
Doctors frequently pretend to knowledge they do not have IRI
0.51
0.59
0.55
5
Doctors often show a pretty shrewd understanding of human nature
0.32
0.39
0.49
6
You can possibly get better medical treatment from so-called 'quacks' than you can from most doctors IRI
0.34
0.43
0.40
7
Doctors deserve the high regard in which they are commonly held
0.43
0.68
0.68
8
A lot of doctors are more interested in money than in helping the patients (RI
0.46
0.55
0.65
9
A doctor is probably the best person to help with a personal problem
0.28
0.47
0.50
0.49
0.59
0.58
2
10 Doctors use their professional standing to get unfair odvantages over people IRI 1 1 A high proportion of doctors are negligent IR)
.
0.33
0.50
0.42
.
12
It is reasonable to choose a medical practitioner to lead a team in a health setting
0.21
0.39
0.37
'
13
Treatments administered by doctors generally have a valid scientific basis
0.36
0.37
0.24
14
Doctors are often deficient in interpersonal skills IR)
0.47
0.59
0.54
15
It requires o high level of ability and hard work to become a doctor
0.26
0.31
0.23
16
Doctors ore often irresponsible in prescribing drugs IRI
0.42
0.55
0.51
Note: ( 0 ) R = reverse scored
sample 3, r = 0.01,278 df; in both cases, P > 0.05. Thus occupational status appears unlikely to have influenced attitudes to medical practitioners. Scores of respondents on the AMPS and the GAIAS for each sample are summarised in Table
5. Mean scores on the two pro-authority scales were highest for the postal sample and lowest for the students. However, it was unclear whether the discrepancy was a result of university attendance or age differences, on average some 14 years. Sex differences appeared small, except for the sample interviewed, in which mean pro-authority scores were higher for males. Analyses of covariance were carried out with first the AMPS and then the GAIAS as dependent variables, using educational status (student o r nonstudent) and sex as independent variables, and with age as covariate. Results confirmed that university attendance (F = 11.71 for the AMPS and 16.79 for the GAIAS)were significant (for all Fvalues, P < 0.001, with non-students (samples2 and 3 combined) and older respondents being more pro-authority. In these analyses sex was not significant. However, s e p arate regression analyses carried out using scores 408
obtained within each of the three samples, showed that for sample 2 (interviewees) sex was a significant factor for the AMPS (F = 7.10, P < 0.01) and also for the GAIAS (F = 16.12, P < 0.01); in each case females were less pro-authority, controlling for age. N o significant differenceswere obtained for sex with the other samples. Given the foregoing analysis, it became necessary to control for both age and sex in examining the relationship between the attitude scales and the validating criteria for each sample. It had been predicted that scores on the AMPS would be positively correlated with scores on the GAIAS. Partial correlations are presented in Table 6, controlling for age and sex. Table 6 shows that the correlations between the AMPS and the GAIAS were positive, significant (P < 0.001) and moderate in size, ranging from 0.44 to 0.60 for each of the three samples of respondents. In addition, correlations with each of the four-item subscales of the GAIAS (the army, the law, teachers and the police) were also positive and significant. It may be concluded that the AMPS is closely related to measures of attitudes towards other institutions notable for the exercise of authority. The validity of the AMPS as a more specific
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posite rating scale. Correlations with this criterion may be regarded as the most reliable. Correlations between the attitude scales (the AMPS and GAIAS) and the validating criteria are given in Table 8, again after partitioning for the contribution of age and sex. AU the correlations between the AMPS and the validating criteria were positive (as predicted) and significant for each of the three samples (see Table 8). These correlationswere small to moderate in size: for the composite rating scale, they ranged from 0.34 to 0.46. Correlations with the AMPS were in all cases higher than those obtained with the GAIAS, suggesting that regardless of sample and or data collection procedure employed the AMPS was a better predictor of scores on the validating criteria. Nevertheless it may be noted that the discrepancy between the sets of correlationsobtained with the two scales was smallest with the interviewed sample. This suggests that in the interview situation, as opposed to one in which selfadministered questionnaires are completed, attitudes to doctors and attitudes to other forms of institutional authorities may have similar implications. It would seem that whilst interacting with another person, the respondents sought to respond with a somewhat higher degree of consistency in relation to the questionnaire items. The higher alpha coefficientsobtained with the interviewed group (see Table 2) gives some support to this interpretation. The question whether it could be claimed that the AMPS adds a significant degree of predictive power to that associated with the GAIAS and other demographic factors was examined using the pooled data (N = 977). Specifically, regression analyses sought to establish whether 1. the AMPS as well as other independent variables, the GAIAS, age and sex (coded as 1 = male, 2 = female), yielded independent contributions in predicting the criteria, and 2. whether the AMPS in particular provided additional predictive power after the effects of the other independent variables had been accounted for.
Table 4: Factor loadings for a principal components analysis for the AMPS for 977 respondents Factor loadings Scale'itema
First unrotated factor
1
2 3 4 5 6 7 8 9 10 11
12 13 14 15
16
0.68 0.66 0.52 0.63 0.52 0.47 0.74 0.66 0.56 0.66
0.52 0.41 0.41 0.65 0.32 0.61
Rotated factors 1
2
3
0.31 0.66' 0.19 0.61 0.08 0.44' 0.39 0.73' 0.17 0.73' 0.65' 0.06 0.08 0.52' 0.00 0.61*
0.51b* 0.27 0.21 0.19 0.64' -0.13 0.59' 0.21 0.74' 0.15 -0.08 0.32 0.12 0.51' 0.1 1 0.31
0.42' 0.09 0.62' 0.20 0.28 0.50' 0.33 0.04 0.09 0.12 0.21 0.45' 0.65' 0.01 0.60' 0.00
Notes.
la1 Item numbers are those given in Table 3. (bl = items with substantial I > 0.401 loadings on rotated factors.
measure of reactions towards doctors was ncxt tested by means of correlations with criteria derived from respondent ratings of the last doctor visited, satisfaction with the consultation and reported compliance with the doctor's advice. In addition to the individual criteria, a more general criterion, a composite rating index, was obtained by summing scores on the seven doctor rating measures (an alpha coefficient of 0.93 for this criterion, considered as a seven-item Likert Scale,jpstifiesthe summating). Mean values for each of the criteria are given in Table 7 together with standard deviations, which indicate the extent of the variability associated with each measure. Respondent ratings tended to be fairly positive and reported compliance was relatively high. The highest degree of variance was found in relation to the com-
Table 5: Mean scores and standard deviations for three samples of respondents on the Attitude to Medical Practitioners Scale (AMPS) and the General Attitude toward Institutional Authority Scale (GAIAS) AMPS
GAIAS
Number
Mean
SD
Mean
77 193 270
.
50.23 49.93 50.01
7.27 7.77 7.61
49.48 49.74 49.67
8.58 7.96' 8.13
153 236 . 389
56.71 . 53.57 54.81
9.94 8.92 9.43
49.47 53.01 51.62
9.39 9.05 9.34
55.58 55.08 55.31
9.16 8.64 8.87
56.70 56.54 56.61
8.33 7.15 7.69
SD
*
Students Male Female Both lnterviewees Male Female Both Postal
Male Female
156
Both
346
190
,
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Table 6: Partial correlations between the AMPS and specific attitude to institutional authority scales from the GAIAS, controlling for sex and age Attitude to authority scales Y
law
Police
Teochers
GAIAS
0.29 0.43 0.30
0.39 0.47 0.36
0.27 0.47 0.32
0.3 1 0.41 0.3 1
0.44 0.60 0.48
h
Students In = 270) lnterviewees In = 389) Postal In = 346)
Note: In each case conelations were significant. P
< 0.001 lone-tail test)
The results for each of the regression analyses followed a similar pattern (Table 9). In each analysis, significant beta coefficients support the independence of the AMPS and also age, (but not the GAIAS) in predicting the validation criteria. Being older and having higher scores on the AMPS independently predicted the last doctor seen being rated more postively, being more satisfied with the consultation, and reporting a higher level of compliance with the doctor’s advice. Being female emerged as a significant factor in predicting a positive rating of doctors as well as reported compliance with the doctor’s advice but not satisfaction with the consultation. Whether a person was a student or not was generally unrelated to the criteria. To check whether the method of data collection affected the results obtained from the regression analysis, the three methods employed were coded and entered as dummy variables, in place of subjects, in a new analysis. The results remained substantially unchanged. Of particular importance for the validity claims of the AMPS, incremental changes in R2 were significant (P< 0.001) in relation to each criterion and this was found to be so after all of the other variables had been entered into the regression analysis. Taking the most reliable of the validation criteria, overall doctor rating, a beta coefficient of 0.447 (P < 0.001) may be taken as indicating the independent strength of the contribution of the AMPS in predicting respondent evaluations of doctor performance.
Discussion It has been argued that in addition to measures of levels of satisfaction with medical care and perceived locus of control for health, it is useful to have measures that are directly relevant to the task of assessing the degree of respect with which doctors are held in a particular community. The development of the AMPS fills a gap in the arsenal of research methodologies. allowing one to make comparisons between communities, and to examine possible differences in respect for doctors by different groups (such as those defined by gender, age, ethnicity and occupational status) within communities. It also enables one to monitor possible changes in medical practitioner authority, and to address validly the question of whether respect for doctors is, as is frequently claimed, now in a state of decline. The AMPS has certain merits that commend themselves for this task. It has been shown to be internally consistent with alpha levels of 0.80 or higher. Moreover, such reliability has been replicated with three different samples of respondents, using diverse methods of data collection. Further, the scale not only has face validity as a measure of respect for doctors but has been shown to be significantly related to measures of attitudes towards other institutional authorities, specifically the police, the law, the army and teachers. The implication is that the AMPS does, in fact, tap some of the same sentimentsfelt towards a
Table 7: Ratings of the last doctor seen according to selected qualities, and levels of satisfaction and compliance for three samples of respondents Mean volues and sbndard deviations for each rating
Satis-
COmpoJte rating
faction
Compliance
3.82 1.07
26.65 5.96
3.28 0.79
4.10 1.07
3.61 1.20
3.93 1.08
27.06
6.56
3.34 0.81
4.10 1.04
3.890 1.13
4.03 1.05
28.10 6.32
3.37 0.87
4.44 0.87
Ilb
R2
R3
R4
RS
R6
261
3.88 0.99
3.76 1.05
3.92 0.97
3.79 1.12
3.97 1.00
3.51 1.1 I
382
3.97 1.00
3.87 1.03
3.98 1.01
3.81 1.16
3.88 1.12
4.05 0.96
3.98 1.03
4.11 1.01
3.94 1.1 I
4.20 0.99
R,
Students Mean Standard
deviation
Intervieweer
lnterviewees Standard deviation
Postal
334
Mean Standard Notes:
deviation
-
(a1 Sample sires are diihtly smaller than in previous tables due to missing coses. Ibl Ratings: Scored on a &point scale, from 1 = extremely dissatisfied to 4 highly satisfied. R = ability to listen to you; R2 = ability to find out what’s wrong; R conxientiausneu; R4 = concern for you as a person; Rg = deserving of respect as a mdical doctor; R6 = personal warmth; R7 = ability to communicate eiectivety. lcl Composite rating is the sum of oU specific ratings, R, to R7 Id1 Satisfaction scored on a &point scde from I = not ot all, to 5 = completely. lel ComplPnce scored on a Spoit xole from 1 = not at all to 5 = completely.
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Table 8: Partial correlations for the AMPS and GAlAS evaluation of the last doctor seen, controlling for age and sex Criteriaa
RZ
R3
R4
RS
R6
R7
Composite rating
Satisfaction
Compliance
0.25b* -0.03
0.26' 0.02
0.26' 0.01
0.34' 0.08
0.34' 0.10'
0.20' 0.04
0.30' 0.04
0.34' 0.02
0.31' 0.03
0.34' 0.16'
lnterviewees (n = 3821 AMPS GAIAS
0.33' 0.26'
0.37' 0.21'
0.33' 0.23'
0.34' 0.23'
0.39' 0.29'
0.33' 0.24'
0.38' 0.30'
0.40' 0.28'
0.38' 0.29'
0.20' 0.19'
Postal survey In= 3341 AM?S GAIAS
0.40' 0.05'
0.40' 0.06'
0.38' 0.13'
0.39' 0.15'
0.45' 0.16'
0.40' 0.20'
0.37' 0.23'
0.46' 0.15'
0.36'
0.31' 0.15'
Rla
Students In = 2611 AMPS GAIAS
Nofes: la1 Details of he criteria ore given in Table 6 (footnote). (b) ' = significont correlation, P
range of other institutions notable for the exercise of authority. Haug and Lavin provided results pointing to a similar conclusion with their own measure of attitudinal challenge to doctors, which they report as correlating significantly (r = 0.31) with a more general measure of rejection of authority.' However, reported correlations between their measure of attitudinal challenge to doctors and potential validating criteria have tended to be nonsignificant or very low. Thus attitudinal challenge was reported as correlating with reported compliance (between -0.0 1 and -0.18).l3 By contrast, both the general attitude toward authority measure (the GAIAS) and the more specific measure (the AMPS) correlated significantly with each of the validating criteria. Moreover, the AMPS was shown to make an independent contribution as a predictor of patient reactions to doctors, and to add significantly to the predictive power provided by the combination of GAIAS, age and sex. It is especially in this last respect that the claims of the AMPS as a valid instrument for assessing attitude towards medical practitioners are advanced.
0.16'
< 0.05 lone-toil test)
There were some incidental findings during development of the AMPS. As in previously reported studies1J3there is evidence that both age and education may influence attitudes toward medical practitioner authority. Older respondents tended to be more positive in their attitudes, and respondents attending university less positive than others. Neither result is surprising; older people tend to be more conservative; university students tend to develop radical social attitudes. In general, sex differencesin attitudes were minimal and, apart from one sample, not significant. As a predictor of reaction to doctors, sex was inconsistent,among criteria and comparatively unimportant, in marked contrast to age. Consistent with their more positive attitudes to medical practitioners, older respondents appeared to evaluate their doctors more highly and report more compliance. Yet even if one considers the least attitudinally positive of the subgroups tested in this study, that is, the student sample, the average respondent still scored higher, albeit slightly, than the neutral point on the AMPS. The majority of the respondents in this study tended to feel positively
Table 9: Regression analysis for the AMPS, GAIAS, sex, subects and age as predictorsof the validating criteria using the complete set oldata ( n = 977) Predictors
Simple R
B
Rating Subiects Sex Age GAIAS AMPS
0.063' 0.03 1 0.234% 0.226% 0.438%
-0.034 0.076t 0.152%
Satisfaction Subiects Sex Age GAIAS AMPS Compliance Subiects
Sex Age GAIAS AMPS
Multiple R
RZ
Rz change
0.449+
0.063 0.078 0.240% 0.291 0.467%
0.004 0.006 0.058 0.085 0.218
0.004 0.003 0.052% 0,0279 0.133*
0.044 0.002 0.185t 0.21 1 0.377%
-0.044% 0.037 0.109% -0.024 0.374%
0.044 0.046 0.1869 0.249% 0.393%
0.002 0.002 0.035 0.062 0.1 54
0.002 0.000 0.032% 0.027% 0.093%
0.075' 0.039 0.21 1 0.237% 0.3079
-0.005 0.08 1 ' 0.136% 0.063 0.2439
0.075 0.094' 0.221 0.286% 0.348%
0.006 0.009 0.049 0.082 0.121
0.006 0.003 0.040% 0.033% 0.039%
+
+
+
-0.064
+
~~~
NO&: P
< 0.05: t P < 0.01: + P
I
Correspondence to Dr K Rigby, School of Social Studies, University of South Australia, Adelaide, SA 5000
Such measures are typically multifaceted, covering a wide range of factors that may be expected to give rise to satisfaction or dissatisfaction with the services provided by doctors. They characteristically include the means of appraising the doctor's conduct, especially in relation to perceived technical competence and interpersonal care,g but also go beyond these. As Patrick et al have shown, such scales are typically and appropriately concerned with matters like the accessibility or convenience of getting an appointment, the mechanism of payment and the availability of doctorss Such scales do not tell us how people feel about doctors themselves. Indeed, a strong feeling that doctors are 'not available enough' might well reflect a positive attitude towards doctors. The development of measures for beliefs about the determinants of a person's health also relates to the question of doctor evaluation. Based upon Rotter's concept of internal and external locus of contro1,'O a number of scales dealing exclusively with health have been developed."J2 Locus of control refers to an expectations people have about ,whether they can effectively control outcomes; if they believe they can, they have an internal locus of control; if they believe outcomes are controlled by others, they have an external locus of control. It may be surmised that patients who have an external rather than an internal locus of control for health outcomes would value doctors relatively highly and accept their authority. Any challenge to medical authority, it seems, would be more likely to come from patients with an internal rather than an external locus of control. However, Lau and Ware's research
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employing a health-specific locus of control measure, controlling for acquiescence set, has shown that belief in personal (internal locus) control and belief in provider (external locus) control were unexpectedly positively and significantly correlated.l 2 The assumption that there is a polarity of internal and external attributions with respect to health was clearly not supported. One cannot therefore infer a challenge to medical authority from a patient with a relatively internal health locus of control if such a person is, in fact, also likely to have a relatively high external health locus of control. Nevertheless, some aspect or factor of a healthspecific locus of control measure may be relevant to the task of assessing community attitudes towards medical practitioners. A possible candidate is the provider-control subscale of the health-specific locus of control measure proposed by Lau and Ware.” This eight-item scale consists of a set of items intended to tap the belief that doctors are effective in helping their patients. It does, however, have some important shortcomings. Despite its narrow range of item content, the internal consistency or reliability of the measure is quite low (a= 0.67). Also its limitation in scope must count against it. It is reasonable to suppose that evaluative reactions towards doctors embrace a much wider range of issues (some of which are included in patient satisfaction scales) than are covered by measures which focus only on the doctor’s perceived helpfulness, important though that must be. In addition, locus of control measures are basically concerned with cognitive aspects of attitudes. Affective or emotional aspects of attitudes towards doctors are at least equally important, as Wolf, Putnam, James and Stiles correctly assumed in constructing their measure of ‘patient’s perception of physician’s behaviour’.IY A further approach to gauging public attitudes towards doctors involves assessing in a relatively direct manner the extent to which people are predisposed to accept or reject medical authority. This approach has much to commend it, since it is unambiguously concerned with evaluation of doctors themselves, whether they are seen as trustworthy, deserving of respect, or alternatively not trustworthy and needing to be challenged. Haug and Lavin pioneered such an approach in their construction of a scale to assess ‘willingness to challenge MD authority’. Unfortunately, that measure was closely modelled upon the California F ScaleI5and as such, made certain questionable assumptions about the nature of attitudes to authority. The Haug and Lavin Scale consists of four forcedchoice items. In each case one may choose the ‘authoritarian-submissive’alternative, for example: ‘Every person should have complete faith in doctors and do what they tell you to do without a lot of questions’ or the corresponding ‘non-authoritarian’ alternative: ‘It’s alright for people to raise questions with doctors about anything they tell you to do’. According to the rationale underlying the F Scale and its derivative formulated by Haug and Lavin, acceptance of authority is part of an authoritarian syndrome which characterises a deeply prejudiced, 404
rigid, repressed and socially undesirable personality. This view has been trenchantly criti~ised’~*’’ and the F Scale itself has been shown to have highly dubious external validity.’&-‘OIt seems likely that the Haug and Lavin Scale is based upon a false dichotomy: that either one challenges medical authority or one is submissively authoritarian. Alternative models for assessing attitudes to authority, with no such built-in assumptions about psychopathology, offer greater promise for the development of an appropriate A recently published scale in this area, the General Attitude towards Institutional Authority Scale (GAIAS) is composed of four significantly intercorrelated subscales, assessing attitudes towards various institutional authorities, namely the police, the army, the law and teachers.“ The GAIAS has avoided assumptions of psychopathologyand irrationality on the part of either supporters or opponents of institutional authorities. Correlations with measures of I Q and self-acceptance have been non~ignificant.‘~.’~ The generality and behavioural validity of the measure has been confirmed in a variety of population^.'^-^^ Since medical practitioners undoubtedly constitute an institutional authority, it was proposed that an appropriate attitude towards medical practitioners scale (or AMPS) should be constructed along lines followed in the construction of the subscales of the GAIAS, but with medical practitioners as the target. This approach involves initially collecting a large number of statements which are judged to imply, quite unambiguously, respect or disrespect for the medical practitioner. Item content may be derived from judgments made in a variety of areas, such as the doctor’s competence, capacity to care and general character. The final arbiter of item-relevance is determined by the capacity of items to show relatively high levels of interrelationship. Although the initial choice of items with this method tends to be intuitive and not theoretical (compared, for instance, with that of locus of control measures), there is good reason to suppose that this method yields measures which not only have enough psychometric properties, but also predict relevant behaviour.YO The qualities required of the proposed scale were: 1. The items should be unambiguously relevant to the issue of respect or disrespect for the authority of doctors; in short, the scale should have face-validity. 2. The scale should contain items which correlate significantly with the scale total, should be balanced to control for acquiescence set, and should show a satisfactory level of internal consistency, as assessed by coefficient alpha. 3. The scale should correlate significantly and positively with other measures of attitude towards institutional authorities, such as the GAIAS and its subscales. This follows from the assumption of a general attitude to authority, which has been confirmed in series of studies with diverse
population^.^^^^^^^ 4.
The scale should yield evidence of concurrent validity based upon criteria clearly relevant to
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positive and negative reactions towards particular medical practitioners. 5. Finally, the AMPS should show greater validity than an alternative, more general measure of attitude to authority, such as the GAIAS, that is, a degree of specific validity should be demonstrated. To establish concurrent validity for the AMPS, one may draw upon the respondents’ reactions towards the last doctor they visited how positively or negatively the doctor was evaluated, and to what extent the doctor’s advice was complied with. Both kinds of criteria are important: the former, since positive ratings would clearly be expected of respondents with a generally high level of respect for medical practitioners, and the latter, since behavioural compliance is especially relevant to the question of acceptance of medical authority. Whilst doing what a doctor says may on occasions result from a doctor being manipulated by a patient to say what the patient wants to hear, it is reasonable to suppose that for the most part the compliant patient is responding positively to a medical authority whom he or she respects. There are problems of assessing compliance, especially outside the hospital setting where one may be forced to rely upon self-report data for which the reliability may be questioned. Highly accurate information on compliance using such an approach may be difficult to achieve. Nevertheless, there is evidence that self-reported ratings of frequencies of compliant and non-compliant behaviours do correlate significantly with corresponding peer-reported ratings, at least under conditions in which the information is provided anonymously so that any tendency to give the socially desirable response is reduced.Y0 A further issue of relevance to the proposed validating scheme concerns the extent to which attitudes and behaviour may be expected to correlate. Following the trail of La Piere$’ and later Wicker,Y2it became fashionable to dismiss the possibility of all but the weakest connections between attitudes and behaviour. Clearly there are substantial and often countervailing situational influences that would tend to weaken any relationship. However, more recent research into the conditions governing attitude/ behaviour consistency has encouraged the belief that where correspondence between an attitudinal and a behavioural measure exists, a real relationship may be f o ~ n d With . ~ ~a ~ single ~ ~ behavioural index, as opposed to a multiple index, the relationship of behaviour to attitude is likely to be comparatively small, yet significant. It follows that a measure of attitudes to medical practitioners should yield small but significant correlations with measures of appropriately corresponding behavior, such as reported compliance with a doctor’s advice given on a particular occasion. I n o b t a i n i n g d a t a f o r this study t w o methodological considerations were considered important: first, to sample among different subpopulations, where possible drawing upon a wide cross-section of respondents, and second, to employ different methods of data collection to demonstrate
that the obtained results did not depend on a particular research method. Students from Australian universities formed one type of respondent; members of the general population of Adelaide, South Australia, the other. Data collection techniques included mass administered questionnaires, individual interviews and a postal survey. Because people are more likely to respond in a socially desirable manner when they are talking to another person, compared with responding privately to a questionnaire item, one might reasonably assume that there were variations between samples because degree of anonymity varied. Analyses of results for subsamples using different respondent types and data collection methods were carried out separately. In this way it was hoped that obtaining results that were consistent across samples would confirm the robust nature of the scale. In summary, it was proposed to develop a scale for the assessment of community attitudes towards medical practitioners that was especially relevant to the question of community respect for their authority. The validity the AMPS was to be investigated by correlation with validating criteria derived from ratings of the last doctor visited and reported compliance with that doctor’s advice. Higher correlations were predicted with these validating criteria than with those obtained using the GAIAS. Replications were intended using different types of respondents (students and non-students) and employing a variety of data gathering procedures.
Methods Initially 40 items, consisting of equal numbers of favourable and unfavourable statements about medical practitioners, were assembled. Some related to the professional competence of doctors, others to more personal of general qualities. Each statement was phrased in such a way that agreement or disagreement with it would indicate a comparatively positive or negative attitude towards doctors in general. For example, agreeing with: ‘doctors generally know what is best for their patients’ implied a positive attitude to the practitioner, ‘a lot of doctors are more interested in money than in helping people’ a negative attitude. Using a Likert format in which scores for each item were summated, high scorers were expected to show favourable and very respectful attitudes toward medical practitioners, low scorers, unfavourable and disrespectful ones. The items were presented as statements that had been made about medical practitioners, and respondents were invited to give their reactions to each of them. The instructions were: write 1 if you agree strongly, 2 if you agree, 3 if you are neutral or uncertain, 4 if you disagree, and 5 if you disagree strongly. The questionnaire was administered to 100 nonstudent respondents who were personally contacted and asked to complete the 40-item questionnaire. The scale proved to be highly reliable, with a Cronbach alpha coefficient of 0.95. It appeared feasible to reduce the length of the scale to 16 items and still preserve adequate reliability. Two versions, Scale A and Scale B, were devised using the items with the
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highest item-total correlations consistent with providing equal numbers of positively and negatively keyed items. Scale A was chosen for use in the major study in which cross-validation would occur. The initial alpha coefficient for Scale A was 0.89; the correlation between the positively and negatively keyed halves (after appropriate item score reversals) was 0.79 (P < 0.001). In the major study reported in this paper, the proposed AMPS was presented with its 16 items interspersed with those comprising the short version of the GAIAS.” This scale also consists of 16 items and has 4 balanced subscales with items tapping attitudes toward the army, the law, teachers and the police. Therefore a 32-item scale was assembled, employing the same format and instructions as those used in the pilot study. The combined AMPS and GAIAS were included in a questionnaire which sought additional information. Respondents were asked to rate the last doctor they saw in terms of each of the following qualities: 1. ability to listen to you, 2. ability to find out what’s wrong, 3. conscientiousness, 4. concern for you as a person, 5. deservingness of respect as a medical doctor, 6. personal warmth, and 7. ability to communicate effectively. A five-point scale was provided for each criterion: 1 very low; 2 fairly low; 3 moderate extent; 4 fairly high, and 5 very high. To assess general satisfaction with the last consultation, respondents were asked to indicate: 1 for extremely dissatisfied, 2 for rather dissatisfied, 3 for moderately satisfied, and 4 for highly satisfied. Compliance was assessed by asking respondents to indicate the extent to which they followed the last doctor’s advice: 1 for not at all, 2 a small extent, 3 about half, 4 to a large extent, and 5 completely. To obtain demographic data, questions were included to provide age, occupation and sex. Respondents’ names were not required. Three samples of respondents were used, each providing information following a different procedure. Sample 1 consisted of first year university students attending classes in the School of Social Studies at the University of South Australia in the cities of Adelaide and Whyalla, and students attending the Northern Territory University in the Northern Territory of Australia. Questionnaires were administered to these respondents in groups. The remaining respondents were nonstudents. One group was contacted by social work students who were each asked, as part of a research assignment, to contact three nonstudents, where possible choosing individuals who differed in occupational status. Occupational status was defined operationally according to the Congalton Scale, a comprehensive list of occupations classified on a seven-point scale according to status values provided by a wide crosssection of the Australian public acting as raters.Y5For the purpose of this inquiry the classifications were collapsed into three categories: high (status 1 and 2), medium (status 3, 4 and 5), and low (status 6 and 7). Respondents were interviewed and while no names 406
were required, the degree of anonymity was obviously lower than in the first sample. Sample 3 was a stratified random sample contacted by l e t t e r . I n ‘an a t t e m p t t o maximise representativeness, names were randomly selected from the South Australian Electoral Roll. Equal numbers of respondents were chosen from Adelaide suburbs classified (according to the Adelaide socioeconomic atlas), as high, medium and low social status.36As the electoral rolls also contained stated occupations for each person listed, only people with occupations of a status (defined by the Congalton Scale) corresponding to their suburbs were selected to form the population from which the final sample of 1 000, half male and half female, was drawn. About one third of the persons to whom letters were sent returned completed questionnaires. Details of sex, age and social status are presented in Table 1 for each of the samples. No attempt was made to identify the social status of the student respondents. For a proportion of nonstudents, especially female respondents, information regarding occupation was not available, and they too were unclassified. From Table 1 it is apparent that, for the most part, the student sample consisted of ‘mature-age’ people, their mean age being about 30 years. The interviewed respondents were, on average, about four years older. The postal survey provided the oldest respondents, on average 44 years. Age variability, as indicated by standard deviations and ranges, was much more evident among the postal respondents. Respondents of the different social status groups were well represented in samples 2 and 3, especially the middle status category. The relatively large proportion of ‘unclassified’females resulted from many of them describing themselves as having ‘home duties’. Results The reliability of the AMPS was examined independently for each of the three samples. Cronbach’s alpha, a measure of overall inter-item consistency, and correlations between positively and negatively keyed halves of the scale are given in Table 2 for the AMPS and, for comparison, for the GAIAS, a measure that figured largely in subsequent analyses. Table 2 shows that upon cross-validation, the AMPS, with alpha coefficients ranging from 0.80 to 0.87, had adequate internal consistency, despite the expected shrinkage in alpha from the original 0.89. Correlations between differently keyed halves were all statistically significant (P < 0.001). This is an important point since it shows that controlling for acquiescence has not occurred, as it sometimes does in the development of unrelated subscales.J7 A detailed analysis of the relationship between each item and the total scale (corrected for the contribution of the item) is presented in Table 3. This shows that every item for each of the three samples correlated significantly with the sum of the remaining items. The validity of each of the items as a contributor to the AMPS was thus confirmed, with correlations ranging from 0.28 to 0.68.
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Table 1 : Age, sex and social status composition of samples
Mean
Age (years) Standard deviation
Range
High
Social status level % Middle Low
Not classified
~~
Sample 1 - students, group questionnaire Males In = 771 29.48 Females In = I931 30.12 Total In = 2701 29.94
8.25 9.44 9.1 1
16-53 16-54 16-54
0.0 0.0 0.0
Sample 2 - nonstudents, interviewed Males In = 1531 Females In = 236) Total In= 389)
35.01 32.34 33.96
9.96 8.63 9.54
18-73 20-64 18-73
33.5 24.2 29.8
39.8 48.4 43.2
25.8 22.9 24.7
0.8 4.6 2.3
Sample 3 - contacted by letter Males ( n = 156) Females In= 1901 Total In= 3461
45.52 42.08 43.63
17.26 16.14 17.72
17-90 17-79 17-90
20.5 4.7 11.9
48.1 52.7 50.6
24.4 13.7 18.5
7.1 28.9 19.1
In order to examine the internal structure of the AMPS, a principal components analysis of the 16-item scale was undertaken using results for the total set of 977 respondents, for whom a subsequent validation study was undertaken (See Table 6). This produced three factors with eigenvalues greater than one. In Table 4 factor loadings are given for each item; first, for Factor 1 in its unrotated form; and then for each of the three factors following varimax rotation. Factor 1 (unrotated) accounted for 33.1 per cent of the variance, each item being substantially loaded on it ( > 0.3). This result confirms the view that each of the items contributed effectively in the assessment of a coherent generalised tendency to evaluate medical practitioners positively or negatively. Varimax rotation enabled us to identify subfactors. The first factor is loaded substantially ( > 0.4) on items that express sentiments critical of doctors. This suggests that such feelings are particularly coherent regardless of their specific content. To some degree, however, this factor may be an artefact of balancing the scale to control for acquiescence set. As already noted, however, the two halves of the scale were positively correlated after reverse scoring, thus supporting the overall integrity of the scale. The second and third factors, accounting for 9.4 per cent and 6.6 per cent of the variance respectively, suggest a distinction between a dimension concerned with the personal helpfulness of doctors (‘a doctor is probably the best person to help with a personal problem’-loading of 0.74 on factor 2), and technical efficiency (‘treatments administered by doctors generally have a valid scientific basis’-loading of 0.65 on factor 3). It has already been noted that the
0.0 0.0 0.0
0.0 0.0 0.0
100.0 100.0 100.0
emergence of factors relating to interpersonal and technical aspects of medical care is commonly found with patient satisfaction scales. With the AMPS, however, they evidently account for a relatively small amount of the scale variance. In order to investigate the relationship between these last two dimensions, subscale scores were computed for sets of items loaded predominantly on one or other of these factors-the ‘personal helpfulness’subscale on items 5, 7, 9 and 14 and the ‘technical efficiency’ subscale on items 3, 6, 13 and 15. The two subscales were found to be moderately correlated (r = 0.46.975 df, P < 0.001). Despite some differentiation suggested by the factor analysis, the overall impression is of coherence. The most central item of the AMPS (as indicated by an unrotated factor loading of 0.74) was: ‘doctors deserve the high regard in which they are commonly held’. This item had loadings of > 0.3 on each one of the rotated factors. It may be taken as catching the essence of what was intended by the scale: a reliable measure of the extent to which members of the community feel respect for the medical profession as an institution. Before seeking to validate the AMPS, it was important to establish whether the extraneous variables for which data were available for each respondent, namely, age and sex, were related to scale scores and potentially capable of determining a significant relationship with validating criteria. Because data on the occupational status variable were missing, especially for the postal survey, this variable was not to be included in the analysis. In the event, correlations between occupational status and the AMPS were very low: for sample 2, r = -0.06, 378 df; for
Table 2: Internal consistency indices for the Attitude to Medical Practitioners Scale (AMPS) and the General Attitude towards Institutional Authority Scale (GAIAS) for three samples of respondents AMPS Sample Students lnterviewees Postal
GAIAS
Number
Alpha
‘pn”
Alpha
‘pn”
270 389 346
0.80 0.87 0.86
0.45 0.59
0.79 0.84 0.77
0.58 0.67 0.48
0.60
Note: la) ‘pn, the conelotion between positively and negatively keyed halves of o scale, wos calculated after appropriate item score reversals.
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Table 3: The Attitudes to Medical PractitionersScale (AMPS). Items for the AMPS with corrected item-total correlationsfor three samples of respondents.
-
Items
1
Students ( n = 270)
lnterviewees ( n = 389)
Postal ( n = 346)
Doctors generally know what is best for their patients Doctors have too much power in our society I R O I
0.46
0.65
0.61
0.52
0.57
0.58
3
It is wise to follow a doctor's directions very carefully
0.47
0.42
0.45
4
Doctors frequently pretend to knowledge they do not have IRI
0.51
0.59
0.55
5
Doctors often show a pretty shrewd understanding of human nature
0.32
0.39
0.49
6
You can possibly get better medical treatment from so-called 'quacks' than you can from most doctors IRI
0.34
0.43
0.40
7
Doctors deserve the high regard in which they are commonly held
0.43
0.68
0.68
8
A lot of doctors are more interested in money than in helping the patients (RI
0.46
0.55
0.65
9
A doctor is probably the best person to help with a personal problem
0.28
0.47
0.50
0.49
0.59
0.58
2
10 Doctors use their professional standing to get unfair odvantages over people IRI 1 1 A high proportion of doctors are negligent IR)
.
0.33
0.50
0.42
.
12
It is reasonable to choose a medical practitioner to lead a team in a health setting
0.21
0.39
0.37
'
13
Treatments administered by doctors generally have a valid scientific basis
0.36
0.37
0.24
14
Doctors are often deficient in interpersonal skills IR)
0.47
0.59
0.54
15
It requires o high level of ability and hard work to become a doctor
0.26
0.31
0.23
16
Doctors ore often irresponsible in prescribing drugs IRI
0.42
0.55
0.51
Note: ( 0 ) R = reverse scored
sample 3, r = 0.01,278 df; in both cases, P > 0.05. Thus occupational status appears unlikely to have influenced attitudes to medical practitioners. Scores of respondents on the AMPS and the GAIAS for each sample are summarised in Table
5. Mean scores on the two pro-authority scales were highest for the postal sample and lowest for the students. However, it was unclear whether the discrepancy was a result of university attendance or age differences, on average some 14 years. Sex differences appeared small, except for the sample interviewed, in which mean pro-authority scores were higher for males. Analyses of covariance were carried out with first the AMPS and then the GAIAS as dependent variables, using educational status (student o r nonstudent) and sex as independent variables, and with age as covariate. Results confirmed that university attendance (F = 11.71 for the AMPS and 16.79 for the GAIAS)were significant (for all Fvalues, P < 0.001, with non-students (samples2 and 3 combined) and older respondents being more pro-authority. In these analyses sex was not significant. However, s e p arate regression analyses carried out using scores 408
obtained within each of the three samples, showed that for sample 2 (interviewees) sex was a significant factor for the AMPS (F = 7.10, P < 0.01) and also for the GAIAS (F = 16.12, P < 0.01); in each case females were less pro-authority, controlling for age. N o significant differenceswere obtained for sex with the other samples. Given the foregoing analysis, it became necessary to control for both age and sex in examining the relationship between the attitude scales and the validating criteria for each sample. It had been predicted that scores on the AMPS would be positively correlated with scores on the GAIAS. Partial correlations are presented in Table 6, controlling for age and sex. Table 6 shows that the correlations between the AMPS and the GAIAS were positive, significant (P < 0.001) and moderate in size, ranging from 0.44 to 0.60 for each of the three samples of respondents. In addition, correlations with each of the four-item subscales of the GAIAS (the army, the law, teachers and the police) were also positive and significant. It may be concluded that the AMPS is closely related to measures of attitudes towards other institutions notable for the exercise of authority. The validity of the AMPS as a more specific
AUSTRALIAN JOURNAL OF PUBLIC HEALTH
1992 vot. 16 NO. 4
ATTITUDES TO MEDICAL PRACTITIONER AUTHORITY
posite rating scale. Correlations with this criterion may be regarded as the most reliable. Correlations between the attitude scales (the AMPS and GAIAS) and the validating criteria are given in Table 8, again after partitioning for the contribution of age and sex. AU the correlations between the AMPS and the validating criteria were positive (as predicted) and significant for each of the three samples (see Table 8). These correlationswere small to moderate in size: for the composite rating scale, they ranged from 0.34 to 0.46. Correlations with the AMPS were in all cases higher than those obtained with the GAIAS, suggesting that regardless of sample and or data collection procedure employed the AMPS was a better predictor of scores on the validating criteria. Nevertheless it may be noted that the discrepancy between the sets of correlationsobtained with the two scales was smallest with the interviewed sample. This suggests that in the interview situation, as opposed to one in which selfadministered questionnaires are completed, attitudes to doctors and attitudes to other forms of institutional authorities may have similar implications. It would seem that whilst interacting with another person, the respondents sought to respond with a somewhat higher degree of consistency in relation to the questionnaire items. The higher alpha coefficientsobtained with the interviewed group (see Table 2) gives some support to this interpretation. The question whether it could be claimed that the AMPS adds a significant degree of predictive power to that associated with the GAIAS and other demographic factors was examined using the pooled data (N = 977). Specifically, regression analyses sought to establish whether 1. the AMPS as well as other independent variables, the GAIAS, age and sex (coded as 1 = male, 2 = female), yielded independent contributions in predicting the criteria, and 2. whether the AMPS in particular provided additional predictive power after the effects of the other independent variables had been accounted for.
Table 4: Factor loadings for a principal components analysis for the AMPS for 977 respondents Factor loadings Scale'itema
First unrotated factor
1
2 3 4 5 6 7 8 9 10 11
12 13 14 15
16
0.68 0.66 0.52 0.63 0.52 0.47 0.74 0.66 0.56 0.66
0.52 0.41 0.41 0.65 0.32 0.61
Rotated factors 1
2
3
0.31 0.66' 0.19 0.61 0.08 0.44' 0.39 0.73' 0.17 0.73' 0.65' 0.06 0.08 0.52' 0.00 0.61*
0.51b* 0.27 0.21 0.19 0.64' -0.13 0.59' 0.21 0.74' 0.15 -0.08 0.32 0.12 0.51' 0.1 1 0.31
0.42' 0.09 0.62' 0.20 0.28 0.50' 0.33 0.04 0.09 0.12 0.21 0.45' 0.65' 0.01 0.60' 0.00
Notes.
la1 Item numbers are those given in Table 3. (bl = items with substantial I > 0.401 loadings on rotated factors.
measure of reactions towards doctors was ncxt tested by means of correlations with criteria derived from respondent ratings of the last doctor visited, satisfaction with the consultation and reported compliance with the doctor's advice. In addition to the individual criteria, a more general criterion, a composite rating index, was obtained by summing scores on the seven doctor rating measures (an alpha coefficient of 0.93 for this criterion, considered as a seven-item Likert Scale,jpstifiesthe summating). Mean values for each of the criteria are given in Table 7 together with standard deviations, which indicate the extent of the variability associated with each measure. Respondent ratings tended to be fairly positive and reported compliance was relatively high. The highest degree of variance was found in relation to the com-
Table 5: Mean scores and standard deviations for three samples of respondents on the Attitude to Medical Practitioners Scale (AMPS) and the General Attitude toward Institutional Authority Scale (GAIAS) AMPS
GAIAS
Number
Mean
SD
Mean
77 193 270
.
50.23 49.93 50.01
7.27 7.77 7.61
49.48 49.74 49.67
8.58 7.96' 8.13
153 236 . 389
56.71 . 53.57 54.81
9.94 8.92 9.43
49.47 53.01 51.62
9.39 9.05 9.34
55.58 55.08 55.31
9.16 8.64 8.87
56.70 56.54 56.61
8.33 7.15 7.69
SD
*
Students Male Female Both lnterviewees Male Female Both Postal
Male Female
156
Both
346
190
,
AUSTRALIAN JOURNAL OF PUBLIC HEALTH 1992
VOL. 1 6 NO. 4
409
RIGBY AND METZER
Table 6: Partial correlations between the AMPS and specific attitude to institutional authority scales from the GAIAS, controlling for sex and age Attitude to authority scales Y
law
Police
Teochers
GAIAS
0.29 0.43 0.30
0.39 0.47 0.36
0.27 0.47 0.32
0.3 1 0.41 0.3 1
0.44 0.60 0.48
h
Students In = 270) lnterviewees In = 389) Postal In = 346)
Note: In each case conelations were significant. P
< 0.001 lone-tail test)
The results for each of the regression analyses followed a similar pattern (Table 9). In each analysis, significant beta coefficients support the independence of the AMPS and also age, (but not the GAIAS) in predicting the validation criteria. Being older and having higher scores on the AMPS independently predicted the last doctor seen being rated more postively, being more satisfied with the consultation, and reporting a higher level of compliance with the doctor’s advice. Being female emerged as a significant factor in predicting a positive rating of doctors as well as reported compliance with the doctor’s advice but not satisfaction with the consultation. Whether a person was a student or not was generally unrelated to the criteria. To check whether the method of data collection affected the results obtained from the regression analysis, the three methods employed were coded and entered as dummy variables, in place of subjects, in a new analysis. The results remained substantially unchanged. Of particular importance for the validity claims of the AMPS, incremental changes in R2 were significant (P< 0.001) in relation to each criterion and this was found to be so after all of the other variables had been entered into the regression analysis. Taking the most reliable of the validation criteria, overall doctor rating, a beta coefficient of 0.447 (P < 0.001) may be taken as indicating the independent strength of the contribution of the AMPS in predicting respondent evaluations of doctor performance.
Discussion It has been argued that in addition to measures of levels of satisfaction with medical care and perceived locus of control for health, it is useful to have measures that are directly relevant to the task of assessing the degree of respect with which doctors are held in a particular community. The development of the AMPS fills a gap in the arsenal of research methodologies. allowing one to make comparisons between communities, and to examine possible differences in respect for doctors by different groups (such as those defined by gender, age, ethnicity and occupational status) within communities. It also enables one to monitor possible changes in medical practitioner authority, and to address validly the question of whether respect for doctors is, as is frequently claimed, now in a state of decline. The AMPS has certain merits that commend themselves for this task. It has been shown to be internally consistent with alpha levels of 0.80 or higher. Moreover, such reliability has been replicated with three different samples of respondents, using diverse methods of data collection. Further, the scale not only has face validity as a measure of respect for doctors but has been shown to be significantly related to measures of attitudes towards other institutional authorities, specifically the police, the law, the army and teachers. The implication is that the AMPS does, in fact, tap some of the same sentimentsfelt towards a
Table 7: Ratings of the last doctor seen according to selected qualities, and levels of satisfaction and compliance for three samples of respondents Mean volues and sbndard deviations for each rating
Satis-
COmpoJte rating
faction
Compliance
3.82 1.07
26.65 5.96
3.28 0.79
4.10 1.07
3.61 1.20
3.93 1.08
27.06
6.56
3.34 0.81
4.10 1.04
3.890 1.13
4.03 1.05
28.10 6.32
3.37 0.87
4.44 0.87
Ilb
R2
R3
R4
RS
R6
261
3.88 0.99
3.76 1.05
3.92 0.97
3.79 1.12
3.97 1.00
3.51 1.1 I
382
3.97 1.00
3.87 1.03
3.98 1.01
3.81 1.16
3.88 1.12
4.05 0.96
3.98 1.03
4.11 1.01
3.94 1.1 I
4.20 0.99
R,
Students Mean Standard
deviation
Intervieweer
lnterviewees Standard deviation
Postal
334
Mean Standard Notes:
deviation
-
(a1 Sample sires are diihtly smaller than in previous tables due to missing coses. Ibl Ratings: Scored on a &point scale, from 1 = extremely dissatisfied to 4 highly satisfied. R = ability to listen to you; R2 = ability to find out what’s wrong; R conxientiausneu; R4 = concern for you as a person; Rg = deserving of respect as a mdical doctor; R6 = personal warmth; R7 = ability to communicate eiectivety. lcl Composite rating is the sum of oU specific ratings, R, to R7 Id1 Satisfaction scored on a &point scde from I = not ot all, to 5 = completely. lel ComplPnce scored on a Spoit xole from 1 = not at all to 5 = completely.
410
AUSTRALIAN JOURNAL OF PUBLIC HEALTH 1992 v a . 16 NO. 4
ATTITUDES T O MEDICAL PRACTITIONER AUTHORITY
Table 8: Partial correlations for the AMPS and GAlAS evaluation of the last doctor seen, controlling for age and sex Criteriaa
RZ
R3
R4
RS
R6
R7
Composite rating
Satisfaction
Compliance
0.25b* -0.03
0.26' 0.02
0.26' 0.01
0.34' 0.08
0.34' 0.10'
0.20' 0.04
0.30' 0.04
0.34' 0.02
0.31' 0.03
0.34' 0.16'
lnterviewees (n = 3821 AMPS GAIAS
0.33' 0.26'
0.37' 0.21'
0.33' 0.23'
0.34' 0.23'
0.39' 0.29'
0.33' 0.24'
0.38' 0.30'
0.40' 0.28'
0.38' 0.29'
0.20' 0.19'
Postal survey In= 3341 AM?S GAIAS
0.40' 0.05'
0.40' 0.06'
0.38' 0.13'
0.39' 0.15'
0.45' 0.16'
0.40' 0.20'
0.37' 0.23'
0.46' 0.15'
0.36'
0.31' 0.15'
Rla
Students In = 2611 AMPS GAIAS
Nofes: la1 Details of he criteria ore given in Table 6 (footnote). (b) ' = significont correlation, P
range of other institutions notable for the exercise of authority. Haug and Lavin provided results pointing to a similar conclusion with their own measure of attitudinal challenge to doctors, which they report as correlating significantly (r = 0.31) with a more general measure of rejection of authority.' However, reported correlations between their measure of attitudinal challenge to doctors and potential validating criteria have tended to be nonsignificant or very low. Thus attitudinal challenge was reported as correlating with reported compliance (between -0.0 1 and -0.18).l3 By contrast, both the general attitude toward authority measure (the GAIAS) and the more specific measure (the AMPS) correlated significantly with each of the validating criteria. Moreover, the AMPS was shown to make an independent contribution as a predictor of patient reactions to doctors, and to add significantly to the predictive power provided by the combination of GAIAS, age and sex. It is especially in this last respect that the claims of the AMPS as a valid instrument for assessing attitude towards medical practitioners are advanced.
0.16'
< 0.05 lone-toil test)
There were some incidental findings during development of the AMPS. As in previously reported studies1J3there is evidence that both age and education may influence attitudes toward medical practitioner authority. Older respondents tended to be more positive in their attitudes, and respondents attending university less positive than others. Neither result is surprising; older people tend to be more conservative; university students tend to develop radical social attitudes. In general, sex differencesin attitudes were minimal and, apart from one sample, not significant. As a predictor of reaction to doctors, sex was inconsistent,among criteria and comparatively unimportant, in marked contrast to age. Consistent with their more positive attitudes to medical practitioners, older respondents appeared to evaluate their doctors more highly and report more compliance. Yet even if one considers the least attitudinally positive of the subgroups tested in this study, that is, the student sample, the average respondent still scored higher, albeit slightly, than the neutral point on the AMPS. The majority of the respondents in this study tended to feel positively
Table 9: Regression analysis for the AMPS, GAIAS, sex, subects and age as predictorsof the validating criteria using the complete set oldata ( n = 977) Predictors
Simple R
B
Rating Subiects Sex Age GAIAS AMPS
0.063' 0.03 1 0.234% 0.226% 0.438%
-0.034 0.076t 0.152%
Satisfaction Subiects Sex Age GAIAS AMPS Compliance Subiects
Sex Age GAIAS AMPS
Multiple R
RZ
Rz change
0.449+
0.063 0.078 0.240% 0.291 0.467%
0.004 0.006 0.058 0.085 0.218
0.004 0.003 0.052% 0,0279 0.133*
0.044 0.002 0.185t 0.21 1 0.377%
-0.044% 0.037 0.109% -0.024 0.374%
0.044 0.046 0.1869 0.249% 0.393%
0.002 0.002 0.035 0.062 0.1 54
0.002 0.000 0.032% 0.027% 0.093%
0.075' 0.039 0.21 1 0.237% 0.3079
-0.005 0.08 1 ' 0.136% 0.063 0.2439
0.075 0.094' 0.221 0.286% 0.348%
0.006 0.009 0.049 0.082 0.121
0.006 0.003 0.040% 0.033% 0.039%
+
+
+
-0.064
+
~~~
NO&: P
< 0.05: t P < 0.01: + P
