Journal of Psychosomatic Research,Vol. 20, pp. 37 to 44. PergamonPress, 1976.Printedin Great Britain
PSYCHOSOMATIC ILLNESS, BIRTH ORDER AND INTELLECTUAL PREFERENCE-I. MEN* PETER SHELDRAKE,
MARGARET
(Received
CORMACK
10 July
and
JAMES MCGUIRE
1975)
Abstract-The paper reports on a survey of students at Edinburgh University, presenting findings for the male respondents. Data was collected on faculty, course, and year of study, on birth order position, and on the reported incidence of a number of illnesses. The incidence of the illnesses in relation to year of study, faculty, and birth order position are first examined, and then the interaction between these variables. The paper ends with a discussion of the sources of the differences found, and the factors that may influence willingness to report illness. FOR SOME time now research in Edinburgh University’s Research Unit on Intellectual Development has been concerned with looking at some of the concomitants of variations in cognitive style, with a particular interest in differences between convergers and divergers [l]. Much of this research has been concerned with looking at dreaming and dream recall [2-41, and with differences in life style, family size, and marriage [5, 61. More recently we have become interested in differences in the incidence of various illnesses, particularly those conventionally labelled as “psychosomatic disorders”, and this paper is a first report on a survey that was carried out in 1974, to look at this area. There have been a number of previous studies which have suggested links between the four variables that interest us, namely cognitive style, intellectual preference, birth order and the reported incidence of illness. First, studies on the reporting of psychosomatic illness among university students have offered some indication of subject differences and the importance of intellectual preference. One study in Edinburgh suggested that, for men, there is a higher susceptibility to emotional disturbance and other manifestations of psychiatric disorders in students in the arts and social sciences faculties as compared to those reading medicine, law or science [7, 81. This study also reported faculty differences for women: as well as reporting more disorders overall the data suggest that women in the arts, science and medicine report more than those in law and social science. A similar study carried out by Ryle [9] at Sussex offered support for the view that the reporting of psychiatric illness is higher in the arts than in the sciences, and higher for women than for men. If we turn to look at studies of the relations of birth order to psychosomatic illness the evidence is somewhat more controversial. A number of studies have suggested that first-boms are more likely to report psychiatric illness, and other related illnesses such as rheumatoid arthritis, e.g. [lO-121 but more recent work suggests that this is more characteristic of first-borns from small families only, and that later-borns also give a relatively high frequency of reporting of such disorders [13]. Schooler argues, in fact, that these differences are a function of family size rather than birth order. However, other research has suggested that asthma is more likely to be affected by “emotionally related” factors in first-borns than in later-borns [14]. In other words, evidence on the relationship of birth order and illness remains problematic.
*Research Unit on Intellectual Development,
23 Buccleuch Place, Edinburgh EH8 9JT, Scotland. 37
38
PETER SHELDRAKE,MARGARETCORMACKand JAMESMcGunts
Our own interest lies in looking at variations in cognitive style, but as this is not easily measured in large-scale surveys, we resorted to looking at two related variablesthose of intellectual preference and birth order. There are, of course, many studies which have suggested that there is an important relationship between birth order and intellectual ability, with first-borns and only children being over-represented in higher education [15, 161.There has been some recent debate over these findings, however cf. [13]. At the same time, a number of studies have shown quite clearly that there is an important relationship between cognitive style and subject preference, with considerable evidence to suggest that convergers tend to prefer the sciences, divergers to prefer the arts [l, 171. These 2 sets of findings suggest that there may well be birth order-cognitive style effects and a recent study of our own has shown that first-borns tend to be more convergent and later-borns tend to be more divergent (with only children falling between these 2 extremes) [18]. With these findings in mind we decided to collect data on the student population of Edinburgh University, asking them to give information about birth order, faculty, year and course and reported incidence of a number of illnesses, in order to investigate the relationships between these variables in more detail. METHOD At Edinburgh University, all students are required to matriculate for each year of the course they are attending, and the majority do so in a period of approximately four weeks at the beginning of the first term of the academic year, During matriculation of 1974 (October) we administered a simple one-page questionnaire to all students who attended the matriculation offices. Altogether 10,051 students matriculated during that month, 9,134 in person and the remainder by post (the questionnaire was not sent to those who matriculated by post). Completion of the questionnaire was not mandatory, but its association with matriculation meant that we had a very high response rate of 88.4%. The questionnaire asked respondents to indicate faculty, year, the degree for which they were registered, whether or not they had experienced asthma, eczema, hay fever, migraine, rheumatoid arthritis, peptic ulcer, high blood pressure, insomnia, nervous tension or nervous exhaustion in the previous 5 yr, and details of their dream recall, and birth order position. The questionnaires for the women included anorexia nervosa in the list of illnesses, and several questions on their menstrual cycles and associated complaints. Altogether there were 10,792 students registered at Edinburgh University for the 74/75 session and the 8,078 students who completed the questionnaire represents 74.9% of this population (the proportions of men and women were 74.3 and 75.6% respectively). We are unable to ascertain how far the sample is representative of the student population as a whole, except in relation to the proportion of men to women, and the proportion of students in each faculty, as shown in Table 1. AS TABLE1.-PROPORTION OF RESPONDENTS ( % AGES)* W0men
Men
Arts
Undergraduate
Postgraduate
Undergraduate
Postgraduate
75.0 (1017)
56.7 (326)
70.8 (1646)
41.1 (168)
Sot. Sciences 73.0 (855)
58.3 (398)
70.3 (1005)
76.2 (214)
Professionalt 79.1 (1353)
29.1 (327)
74.6 (616)
19.7 (66)
Sciences
39.3 (461)
wk.8 (594)
39.8 (103)
83.4 (1659)
*Numbers in brackets refer to the actual numbers.
TMedicine, Law, Veterinary Medicine.
Table 1 suggests, we had a relatively high proportion of completed forms from the undergraduate population, and it is likely that the sample is fairly representative of these, but the same cannot be
Psychosomatic
illness, birth order and intellectual preference-I.
39
Men
said for the post-graduate sample. Many postgraduates do not, in fact, matriculate at the beginning of the year, especially those who are registered for various diploma courses, etc. and the sample contains a higher proportion of those reading for higher degrees than the overall percentages indicate. In all sections of this paper, except where looking at year differences, undergraduate and graduate responses are merged, as the differences between them were insignificant. In this paper we look at the findings for the men only; those for women will be the subject of a subsequent paper.
FINDINGS (a) Principal variables 1. Faculty. Tables 2, 3 and 4 show the faculty, year and birth order differences in the reporting of the various illnesses, (these results are for the total sample as differences between undergraduate and graduate responses are minimal). If we look at faculty differences it is clear that the general findings reported by Kapur and Ryle are sustained and there is a higher reporting of illness as a whole by arts students than by those in the social sciences, whereas the science students show a relatively low incidence of reporting. In particular the arts students gave reports of a high incidence of migraine, nervous tension, nervous exhaustion and insomnia, as well as being high on peptic ulcer, rheumatoid arthritis, high blood pressure and hay fever. Science students gave low reports of migraine, nervous tension, nervous exhaustion and peptic ulcer and reported a fairly low incidence of insomnia. Comparisons between the reported incidence for migraine, nervous tension, insomnia and nervous exhaustion is particularly revealing of the difference between the arts and science students, with the arts students reporting an average of 66.7% more of those illnesses than the science students. Further, this clear difference between the arts and science students appears in relation to those illnesses which are conventionally (i.e. in lay terms) identified with stress, the arts students being high in the reporting of these “stress-related illnesses”, the science students being low, (these illnesses including nervous tension, nervous exhaustion, insomnia and migraine, as above, and also peptic ulcers and high blood pressure). TABLE 2.-_%
AGE
REPORTING
ILLNESS BY FACULTY*
11.6
5.4
7.5
2.2
1.4
0.8
3.8
2.7
17.4
fi-917
SocialSciences 12.2
7.8
4.7
6.3
1.3
0.8
0.6
4.7
2.2
14.6
N-87"
Professioml' 9.8
6.1
3.0
6.7
1.0
1.5
0.3
2.9
2.8
17.)
ii-1175
Science
7.0
3.0
5.8
1.2
0.4
0.5
3.9
3.0
17.0
K-1581
lirta
16.9
10.0
N = 4543.
*Undergraduates
TABLET.-_% Insomnia
Nervous
Year
Tension
and graduates-men
only.
AGEREPORTINGILLNESBYYEAR(IJNDERGRADUATESONLY)
Nervous
Migraine
Exhaustion
High Blood PI-e*SUre
Peptic Ulcers
Rheumatoid Arthritis
Asthma
Eczema
Hay Fever
1
7.0
5.4
2.1
0.7
0.2
0.1
3.8
2.2
15.9
N-1093
2
9.0
6.1
3.7
'6.1
1.7
1.0
0.9
5.0
2.7
17.4
N-963
3
12.2
8.2
3.6
6.7
1.3
0.9
0.4
3.6
3.0
17.6
N-929
4
16.9
10.7
6.0
7.4
1.6
1.3
0.5
3.2
3.9
16.9
w747
5.
17.4
a.3
6.1
8.3
2.3
3.0
0.8
6.0
1.5
22.6
x-133
14:o
12.3
1.8
8.9
1.8
1.8
0.0
5.3
3.5
21.1
tG- 57
6+
N = 3922.
*Veterinary
5.9
and Medical students
only.
TMedical students
only.
PETERSHELDRAKE,MARGARET CORMACK and JAMESMCGUIRE TABLE4.-x
N = 4740.
AGE REPORTING ILLNESS BY BIRTH ORDER POSITION
*“Other only” refers to children with siblings who are 7 or more years older or
younger. The third faculty group that we looked at we have labelled “professionals”. This includes students reading law, medicine, or veterinary medicine. In many ways this group is similar to the scientists in the population with the majority of “stress-related” illnesses showing relatively infrequent reporting among the students-although students of medicine gave a relatively high incidence of reports of migraine, and the law students gave relatively frequent reports of nervous exhaustion. These students also reported a relatively high incidence of peptic ulcers. In other words, students reading for professional subjects appear to be very similar to those reading subjects in the sciences. In the same way students reading for the social sciences are similar to arts students in the pattern of their reporting of illnesses, with the incidence of some illnesses appearing midway between the reported extremes for arts and science students; but they differ from all the other three groups in having a high incidence of reporting asthma and a relatively low incidence of reports of hay fever and eczema. 2. Year. These findings on the differences between the faculty groups in relation to what we have termed stress-related illnesses is given support in Table 3 by the change in incidence in the reporting of illness according to the year of the course. On the assumption that academic work, and therefore academic pressures, increase year by year, we would expect those illnesses that were directly related to stress to increase year by year, whereas those whose aetiology is more complex would not show such a straightforward relationship. This is indeed the case. A clear year by year increase in the incidence of the reporting of illness is found for migraine, nervous tension, nervous exhaustion and insomnia. A general pattern of increase year by year is shown by eczema, hay fever, peptic ulcer and high blood pressure, but there is no clear year pattern shown for the reporting of asthma or rheumatoid arthritis. 3. Birth order. Finally, when we turn to look at the distribution of reported illnesses by birth order position, as in Table 4, we find that only children tend to report more illnesses, and particularly more stress-related illnesses, than the others. This is particularly true for “true only” children who give a high incidence of reports of nervous tension, nervous exhaustion and insomnia, although they give low reports of migraine. In contrast, first-born children give low reports of nervous tension and nervous exhaustion and are also fairly low in the reporting of insomnia, but they offer fairly high reports of migraine. Later-borns seem to fall somewhat between these two groups, with higher reports of migraine and insomnia and fairly average incidence of reporting for most of the other illnesses. In the table we have distinguished one other birth order group-“other only” children, these being children who were brought up with siblings at 7 or more years distant from them. As the table shows, this group is more variable than any of the others, tending to be like true only children in reporting some illnesses-mainly the stress-related ones-but quite unlike them in othes. We have also included data on twins, of whom there were 67 in the sample: as the numbers are small we have left these for interest only, and they are not commented on in relation to Table 4, or any of the other subsequent tables in which they appear. Not surprisingly, there are differences in the proportion of first, only and later-born children between the faculties, as shown in Table 5, with only children being over-represented in the arts and science faculties, (less so in the social science faculty) and first and later-born children being over-represented in the science and professional subjects faculties. In the next section of this paper we want to go on to look at the interaction of birth order, faculty and the reporting of illness.
(b) Znteracrion between variables 1. Faculty, birth order and illness. In Table 6, we look at the percentage reporting illness by facuhy and birth order position (in this, and in the subsequent table, we looked only at the reported incidence
Psychosomatic
illness, birth order and intellectual preference-l.
Men
41
TABLE K-BIRTH ORDERBYFACULTY ( %AGES)
First Arts
Born
Later
Born
Only
‘Other
20.1
18.0
24.5
23.8
Only’*
Tvin 28.1
17.4
20.6
19.0
21.1
15.6
Professions
26.6
26.2
22.9
25.0
23.4
Science
36.0
35.1
33.6
30.1
32.8
Social
Science
N= 4465.
*See Table 4,footnote
*.
TABLET.--0/d AGE REPORTINGILLNESSBYFACLJL~
AND BIRTHORDERPOSITION
of nervous tension, insomnia, migraine and hay fever-the numbers are too small to allow systematic comparisons for the other illnesses). As the table shows, for nervous tension, arts and social science students tend to report more illness than those studying professional subjects and science. This pattern is supported within the birth order groups, except in the case of only children studying professional subjects, where the frequency of reporting rises, and in the case of “other only” children studying science, where the proportion rises again. Similarly, other only students studying the social sciences tend to report less nervous tension. Similarly the faculty variations do not alter the basic birth order pattern of reporting with only children reporting more illness than first-borns and later-borns. However, “other only? tend to vary somewhat. An essentially Cmilar pattern is revealed for the reporting of insomnia. Arts students report more insomnia than students in other faculties. This pattern is repeated within the birth order groups, except that only children studying professional subjects tend to give relatively frequent reports as do “other onlys” studying the social sciences or science. Also, later-born social scientists tend to report a relatively high amount of insomnia. Within faculties, once again, we find the birth order pattern of only children reporting more than later-borns and first-borns supported. “Other onlys” tend to report a fairly high incidence of insomnia, but there are variations for this birth order group. In the case of migraine we find that the incidence of reporting follows a somewhat different pattern, the faculties with students in the arts and professional subjects reporting more than those studying social science, with scientists falling in the middle. This pattern is supported within the birth order groups, except that both only and “other only” social science students tend to report more migraine than others. Within the faculties the birth order pattern of only children reporting more than laterborns and first-borns is not clear, although “other only? report least of all. These differences are found within faculties, except that “other onlys” tend to give low reports in the social science faculty and only children give relatively high reports in this faculty. Finally in the case of hay fever we find, once again, that the arts students report a high amount of hay fever, but in this case they are joined by students reading science and professional subjects, and all these report more than social science students. Within the various birth order groups we find that there is reasonable support for these faculty differences but only child students in the social sciences give high reports and only children in the arts give low reports; also, “other only” children in science and the professional subjects tend to give relatively low reports. Within the faculties the overall birth
N = 3757.
Later Born
First Born
0.0
3.2
1
27.1
4
9.1
6.6
4.5
8.2
15.9
1
2
15.0
6
19.4
13.0
40.5 23.4
4
14;l
'5
9.4 13.8
3
6.8
6.9
11.8
6
10.3
19.0
2.7
7.7
18.9
6.3
8.8
3.8
10.4
4.6 '10.6
5.9
10.6
0.0
20.0
11.1
11.1
0.0
30.8
0.0
5
7.3
10.8 14.7
6.0
6.6
9.1
3
8.8
12.8
2
27.3
46.2 15.4
0.0
5.3 14.3
21.1
1
6
5
4
2
19.4
7.3
7.4
8.0
6.6
0.0
8.3
0.0
4.1
tFigures
9.1
10.0
6.4
12.5
4.0
4.0
1.8
5.9
11.9
5.9
3.4
5.0
6.6
0.0
6.7
7.7
0.0
11.0
7.0
9.9
7.5
8.2 8.5
6.5
12.5
6.2
10.3
4.9
6.1
9.7
3.5
8.8
18.2
7.7
2.0
7.7
11.1
5.3 0.0
6.5 0.0
5.6
8.8
6.0
0.0
7.4
2.6
Migraine HOT Fever
ONLY)?.
10.6
7.5
2.7
4.0
9.8
8.8
6.0
3.3
0."
15.4
0.0
0.0
7.7
14.3
6.3
0.0
6.5
5.0
8.5
9.7
8.1
9.0
8.0
12.5
14.3
2.9
5.7
3.0
7.5
4.7
9.8
4.8
5.4
6.1
2.4
9.9
5.9
0.0
6.7 11.1
5.6
0.0
0.0
5.3
2.u
0.0
7.7
0.0
9.1
9.1
0.0
11.1
4.8
4.0
4.2
14.3
13.2
23.2
13.6
25.0
23.1
11.5
18.7
27.3
30.8
15.8
31.6
22.2
17.6
14.8
23.3
12.8
13.9
20.3
12.0
4.9
19.4
14.0
13.1
18.2
23.1
18.2
28.6
15.4
14.3
31.3
30.0
15.0
25.5
13.9
16.2
18.8
13.4
35.3
21.4
22.1
16.1
14.9
14.2
11.1
20.0
30.8
15.0
9.1
18.2
33.3
22.2
33.3
28.0
29.2
13.4
21.0
14.1
16.2
20.0
12.0
18.3
16.4
7.7
5.6
22.2
9.7
23.7
16.0
20.7
33.3
Aits soc sci ~rof Sciencearts soc Sci ~rof Science
6.9
6.5
Science
ANDBIRTHORDERPOSITION(UNDERGRADUATES
are only given where a box contains at least 10 cases.
19.0 23.4
11.3 10.0
13.4
9.1' 5.3
16.7
10.8
5.1
8.8
0.0
15.4
15.8
0.0 14.3
14.3 11.8
36.4
7.7
7.1
0.0
12.0
27.3
5.6
14.1
0.0 0.0
6
11.8
20.0 11.1
8.3
8.0 10.5
19.0
10.3
25.0
5.6 23.1
8.0
8.3
Insomnia Sot Sci Prof
5
32.4 14.3
0.0
4
18.5
3
13.3
1
2
Nervous Tension Sot Sci Prof Science Arts
REPORTING ILLNESS BYYEAR
*See Table 4, footnote*.
'Other Only''3
Only Children
Arts
Year
TABLE 7.-_% AGE
95
9
h- 47
x-288
N-375
N-403
N=48?
!P ib
Ic=42
EI=*iL
N=34>
x=371
h=4li,
N=
N= 50
I\'= 57
X- 68
f;=63
N= 11
N= 12
s=13ii
N-119
Ii-91
N-
h
Psychosomatic
illness, birth order and intellectual
preference-I.
Men
43
order pattern of first and later-borns reporting less than onlys and “other only? is again given reasonable support. 2. Faculty, birth order, year and illness. Finally, in Table I we look at the reporting of illness by birth order and year (in this case looking at undergraduates only). From the results reported in Table 3 we suggested that nervous tension and insomnia might be regarded as “stress related” illness, migraine as intermediate and hay fever as showing no simple relationship to stress (at least as indicated by increasing course demands). In the case of nervous tension and insomnia, then, there is an overall increase year by year in reporting. When we look within the birth order groups we find that this is supported for only, other only and first-borns, although in all these cases there is a slight tendency for the reporting of illness to drop in the later years. In the case of later-borns we find there is a tendency for reports to drop and rise again in the middle years. In the case of migraine where the overall pattern is one of a rise in the reporting of illness, also, we find that the birth order groups all tend to support this pattern with only children and other only children tending to report less in the later years. Finally, in looking at hay fever, we find once more, for the overall pattern-which is a tendency to report more hay fever in the middle years of the course except for arts students who tend to rise all the way through-all the birth order groups tend to support the distribution. However only child scientists tend to report least in the middle years, first-born students studying professional subjects tend to rise all the way through and later-born arts and science students show a somewhat less clear-cut pattern. CONCLUSION
The data we have collected in this survey of reported illness in students is complex. Nonetheless there are a number of findings which emerge from this preliminary analysis. If we look at our major variables, it is clear that arts students tend to report more illness than students in the sciences, along with students reading professional subjects who also tend to report a relatively low incidence of most illnesses, and students in the social sciences fall somewhat in the middle. This finding is particularly clear in the case of those illnesses which apparently show a fairly straightforward relationship to stress, as indicated by increasing course demands: i.e. nervous tension, nervous exhaustion, insomnia, and migraine. Similarly, and again with particular reference to this set of “stress related” illnesses, we find that “only children” tend to report more illnesses than first-borns and later-borns. The reporting of illness by “other only” children-those with a large gap between themselves and their siblingstends to be more variable in comparison with these other groups, however. These findings suggest that a greater incidence of various illnesses is reported by students whose intellectual preference lies in areas concerned with expression and communication and, equally, students whose birth position is one where they may have been more reliant on communication with adults. These findings are supported when we look at the results in a more detailed fashion and examine variations within the faculties, within birth order groups and within years. They suggest that an expressive or adult-oriented approach is influential in shaping the reporting of illness: these data cannot tell us, of course, whether or not students in the other groups are equally susceptible to the illnesses that we have surveyed but tend to repress them, or if they are, in fact, less common. In a second paper we hope to describe the comparable data that was collected for the women students in the sample, and in subsequent papers we will go on to look at inter-relations between illness, and other influences on the reporting of illness. REFERENCES 1. HUDSON L. Contrary Imaginations. Methuen. London (1966). 2. AUSTINM. D. Dream re& and the bias of intellectual ability. Nature, Vol. 231 pp. 59-60 (1971). 3. HOLMES M. A. M. REM sleep patterning and dream recall in convergers and divergers: Evidence for different defensive preferences. Occasional Paper 16, Centre for Research in the Educational Sciences, University of Edinburgh (1973).
44
PETERSHELDRAKE,MARGARETCORMACKAND JAMESMCGUIRE
4. SHELDRAKEP. and CORMACKM. Dream recall and the menstrual cycle. .I. Psychosom. Res. 18, 347 (1974). 5. HUDSONL., JACOBB. and SHELDRAKE P. Lieben und Arbeiten: Patterns of marriage and patterns of work. Occasional Paper 12, Centre for Research in the Educational Sciences, University of Edinburgh (1973). 6. HUDSONL. Fertility in the arts and sciences. Sci. Studies 3, 305-308 (1973). 7. KAFVR R. L. Student wastage: An epidemiological inquiry into psychiatric and allied factors contributing to it. Unpublished Doctorial Dissertation, University of Edinburgh (1964). 8. KIDD C. B. Epidemiological factors in mental illness: Psychiatric morbidity among students. Unpublished Doctoral Dissertation, University of Edinburgh (1963). 9. RYLE A. Student Casualties. Allen Lane and The Penguin Press, London (1973). 10. SCH~~LERC. Birth order and hospitalisation for schizophrenia. J. Abnorm. Social Psychol. 69, 574 (1964). 11. CHEN F. and COBBS. Family structure in relation to health and disease. J. Cl~ron. Dis. 12, 544 (1960). 12. ERLENMEYER-KIMLING L., VAN DEN BOSCHE. and DENHAMB. The problem of birth order and schizophrenia: A negative conclusion. Brit. J. Psych&. 115, 659 (1969). 13. SCXI~LER C. Birth order effects: Not here, not now! Psychol. Bull. 78, 161 (1972). 14. WEISS J. H. Birth order and asthma in children. J. Psychosom. Res. 12, 137 (1968). 15. SCPACHTERS. Birth order, eminence and higher education. Am. Sociological Rev. 28, 757 (1963). 16. ALTUS W. D. Birth order and its sequence. Science 151, 44 (1966). 17. HUDSONL. Frames of Mind. Methuen, London (1968). 18. SULLOWAYF. and MCGUIRE J. Birth order and cognitive style, to be published (1976).
PSYCHOSOMATIC ILLNESS, BIRTH ORDER AND INTELLECTUAL PREFERENCE-I. MEN* PETER SHELDRAKE,
MARGARET
(Received
CORMACK
10 July
and
JAMES MCGUIRE
1975)
Abstract-The paper reports on a survey of students at Edinburgh University, presenting findings for the male respondents. Data was collected on faculty, course, and year of study, on birth order position, and on the reported incidence of a number of illnesses. The incidence of the illnesses in relation to year of study, faculty, and birth order position are first examined, and then the interaction between these variables. The paper ends with a discussion of the sources of the differences found, and the factors that may influence willingness to report illness. FOR SOME time now research in Edinburgh University’s Research Unit on Intellectual Development has been concerned with looking at some of the concomitants of variations in cognitive style, with a particular interest in differences between convergers and divergers [l]. Much of this research has been concerned with looking at dreaming and dream recall [2-41, and with differences in life style, family size, and marriage [5, 61. More recently we have become interested in differences in the incidence of various illnesses, particularly those conventionally labelled as “psychosomatic disorders”, and this paper is a first report on a survey that was carried out in 1974, to look at this area. There have been a number of previous studies which have suggested links between the four variables that interest us, namely cognitive style, intellectual preference, birth order and the reported incidence of illness. First, studies on the reporting of psychosomatic illness among university students have offered some indication of subject differences and the importance of intellectual preference. One study in Edinburgh suggested that, for men, there is a higher susceptibility to emotional disturbance and other manifestations of psychiatric disorders in students in the arts and social sciences faculties as compared to those reading medicine, law or science [7, 81. This study also reported faculty differences for women: as well as reporting more disorders overall the data suggest that women in the arts, science and medicine report more than those in law and social science. A similar study carried out by Ryle [9] at Sussex offered support for the view that the reporting of psychiatric illness is higher in the arts than in the sciences, and higher for women than for men. If we turn to look at studies of the relations of birth order to psychosomatic illness the evidence is somewhat more controversial. A number of studies have suggested that first-boms are more likely to report psychiatric illness, and other related illnesses such as rheumatoid arthritis, e.g. [lO-121 but more recent work suggests that this is more characteristic of first-borns from small families only, and that later-borns also give a relatively high frequency of reporting of such disorders [13]. Schooler argues, in fact, that these differences are a function of family size rather than birth order. However, other research has suggested that asthma is more likely to be affected by “emotionally related” factors in first-borns than in later-borns [14]. In other words, evidence on the relationship of birth order and illness remains problematic.
*Research Unit on Intellectual Development,
23 Buccleuch Place, Edinburgh EH8 9JT, Scotland. 37
38
PETER SHELDRAKE,MARGARETCORMACKand JAMESMcGunts
Our own interest lies in looking at variations in cognitive style, but as this is not easily measured in large-scale surveys, we resorted to looking at two related variablesthose of intellectual preference and birth order. There are, of course, many studies which have suggested that there is an important relationship between birth order and intellectual ability, with first-borns and only children being over-represented in higher education [15, 161.There has been some recent debate over these findings, however cf. [13]. At the same time, a number of studies have shown quite clearly that there is an important relationship between cognitive style and subject preference, with considerable evidence to suggest that convergers tend to prefer the sciences, divergers to prefer the arts [l, 171. These 2 sets of findings suggest that there may well be birth order-cognitive style effects and a recent study of our own has shown that first-borns tend to be more convergent and later-borns tend to be more divergent (with only children falling between these 2 extremes) [18]. With these findings in mind we decided to collect data on the student population of Edinburgh University, asking them to give information about birth order, faculty, year and course and reported incidence of a number of illnesses, in order to investigate the relationships between these variables in more detail. METHOD At Edinburgh University, all students are required to matriculate for each year of the course they are attending, and the majority do so in a period of approximately four weeks at the beginning of the first term of the academic year, During matriculation of 1974 (October) we administered a simple one-page questionnaire to all students who attended the matriculation offices. Altogether 10,051 students matriculated during that month, 9,134 in person and the remainder by post (the questionnaire was not sent to those who matriculated by post). Completion of the questionnaire was not mandatory, but its association with matriculation meant that we had a very high response rate of 88.4%. The questionnaire asked respondents to indicate faculty, year, the degree for which they were registered, whether or not they had experienced asthma, eczema, hay fever, migraine, rheumatoid arthritis, peptic ulcer, high blood pressure, insomnia, nervous tension or nervous exhaustion in the previous 5 yr, and details of their dream recall, and birth order position. The questionnaires for the women included anorexia nervosa in the list of illnesses, and several questions on their menstrual cycles and associated complaints. Altogether there were 10,792 students registered at Edinburgh University for the 74/75 session and the 8,078 students who completed the questionnaire represents 74.9% of this population (the proportions of men and women were 74.3 and 75.6% respectively). We are unable to ascertain how far the sample is representative of the student population as a whole, except in relation to the proportion of men to women, and the proportion of students in each faculty, as shown in Table 1. AS TABLE1.-PROPORTION OF RESPONDENTS ( % AGES)* W0men
Men
Arts
Undergraduate
Postgraduate
Undergraduate
Postgraduate
75.0 (1017)
56.7 (326)
70.8 (1646)
41.1 (168)
Sot. Sciences 73.0 (855)
58.3 (398)
70.3 (1005)
76.2 (214)
Professionalt 79.1 (1353)
29.1 (327)
74.6 (616)
19.7 (66)
Sciences
39.3 (461)
wk.8 (594)
39.8 (103)
83.4 (1659)
*Numbers in brackets refer to the actual numbers.
TMedicine, Law, Veterinary Medicine.
Table 1 suggests, we had a relatively high proportion of completed forms from the undergraduate population, and it is likely that the sample is fairly representative of these, but the same cannot be
Psychosomatic
illness, birth order and intellectual preference-I.
39
Men
said for the post-graduate sample. Many postgraduates do not, in fact, matriculate at the beginning of the year, especially those who are registered for various diploma courses, etc. and the sample contains a higher proportion of those reading for higher degrees than the overall percentages indicate. In all sections of this paper, except where looking at year differences, undergraduate and graduate responses are merged, as the differences between them were insignificant. In this paper we look at the findings for the men only; those for women will be the subject of a subsequent paper.
FINDINGS (a) Principal variables 1. Faculty. Tables 2, 3 and 4 show the faculty, year and birth order differences in the reporting of the various illnesses, (these results are for the total sample as differences between undergraduate and graduate responses are minimal). If we look at faculty differences it is clear that the general findings reported by Kapur and Ryle are sustained and there is a higher reporting of illness as a whole by arts students than by those in the social sciences, whereas the science students show a relatively low incidence of reporting. In particular the arts students gave reports of a high incidence of migraine, nervous tension, nervous exhaustion and insomnia, as well as being high on peptic ulcer, rheumatoid arthritis, high blood pressure and hay fever. Science students gave low reports of migraine, nervous tension, nervous exhaustion and peptic ulcer and reported a fairly low incidence of insomnia. Comparisons between the reported incidence for migraine, nervous tension, insomnia and nervous exhaustion is particularly revealing of the difference between the arts and science students, with the arts students reporting an average of 66.7% more of those illnesses than the science students. Further, this clear difference between the arts and science students appears in relation to those illnesses which are conventionally (i.e. in lay terms) identified with stress, the arts students being high in the reporting of these “stress-related illnesses”, the science students being low, (these illnesses including nervous tension, nervous exhaustion, insomnia and migraine, as above, and also peptic ulcers and high blood pressure). TABLE 2.-_%
AGE
REPORTING
ILLNESS BY FACULTY*
11.6
5.4
7.5
2.2
1.4
0.8
3.8
2.7
17.4
fi-917
SocialSciences 12.2
7.8
4.7
6.3
1.3
0.8
0.6
4.7
2.2
14.6
N-87"
Professioml' 9.8
6.1
3.0
6.7
1.0
1.5
0.3
2.9
2.8
17.)
ii-1175
Science
7.0
3.0
5.8
1.2
0.4
0.5
3.9
3.0
17.0
K-1581
lirta
16.9
10.0
N = 4543.
*Undergraduates
TABLET.-_% Insomnia
Nervous
Year
Tension
and graduates-men
only.
AGEREPORTINGILLNESBYYEAR(IJNDERGRADUATESONLY)
Nervous
Migraine
Exhaustion
High Blood PI-e*SUre
Peptic Ulcers
Rheumatoid Arthritis
Asthma
Eczema
Hay Fever
1
7.0
5.4
2.1
0.7
0.2
0.1
3.8
2.2
15.9
N-1093
2
9.0
6.1
3.7
'6.1
1.7
1.0
0.9
5.0
2.7
17.4
N-963
3
12.2
8.2
3.6
6.7
1.3
0.9
0.4
3.6
3.0
17.6
N-929
4
16.9
10.7
6.0
7.4
1.6
1.3
0.5
3.2
3.9
16.9
w747
5.
17.4
a.3
6.1
8.3
2.3
3.0
0.8
6.0
1.5
22.6
x-133
14:o
12.3
1.8
8.9
1.8
1.8
0.0
5.3
3.5
21.1
tG- 57
6+
N = 3922.
*Veterinary
5.9
and Medical students
only.
TMedical students
only.
PETERSHELDRAKE,MARGARET CORMACK and JAMESMCGUIRE TABLE4.-x
N = 4740.
AGE REPORTING ILLNESS BY BIRTH ORDER POSITION
*“Other only” refers to children with siblings who are 7 or more years older or
younger. The third faculty group that we looked at we have labelled “professionals”. This includes students reading law, medicine, or veterinary medicine. In many ways this group is similar to the scientists in the population with the majority of “stress-related” illnesses showing relatively infrequent reporting among the students-although students of medicine gave a relatively high incidence of reports of migraine, and the law students gave relatively frequent reports of nervous exhaustion. These students also reported a relatively high incidence of peptic ulcers. In other words, students reading for professional subjects appear to be very similar to those reading subjects in the sciences. In the same way students reading for the social sciences are similar to arts students in the pattern of their reporting of illnesses, with the incidence of some illnesses appearing midway between the reported extremes for arts and science students; but they differ from all the other three groups in having a high incidence of reporting asthma and a relatively low incidence of reports of hay fever and eczema. 2. Year. These findings on the differences between the faculty groups in relation to what we have termed stress-related illnesses is given support in Table 3 by the change in incidence in the reporting of illness according to the year of the course. On the assumption that academic work, and therefore academic pressures, increase year by year, we would expect those illnesses that were directly related to stress to increase year by year, whereas those whose aetiology is more complex would not show such a straightforward relationship. This is indeed the case. A clear year by year increase in the incidence of the reporting of illness is found for migraine, nervous tension, nervous exhaustion and insomnia. A general pattern of increase year by year is shown by eczema, hay fever, peptic ulcer and high blood pressure, but there is no clear year pattern shown for the reporting of asthma or rheumatoid arthritis. 3. Birth order. Finally, when we turn to look at the distribution of reported illnesses by birth order position, as in Table 4, we find that only children tend to report more illnesses, and particularly more stress-related illnesses, than the others. This is particularly true for “true only” children who give a high incidence of reports of nervous tension, nervous exhaustion and insomnia, although they give low reports of migraine. In contrast, first-born children give low reports of nervous tension and nervous exhaustion and are also fairly low in the reporting of insomnia, but they offer fairly high reports of migraine. Later-borns seem to fall somewhat between these two groups, with higher reports of migraine and insomnia and fairly average incidence of reporting for most of the other illnesses. In the table we have distinguished one other birth order group-“other only” children, these being children who were brought up with siblings at 7 or more years distant from them. As the table shows, this group is more variable than any of the others, tending to be like true only children in reporting some illnesses-mainly the stress-related ones-but quite unlike them in othes. We have also included data on twins, of whom there were 67 in the sample: as the numbers are small we have left these for interest only, and they are not commented on in relation to Table 4, or any of the other subsequent tables in which they appear. Not surprisingly, there are differences in the proportion of first, only and later-born children between the faculties, as shown in Table 5, with only children being over-represented in the arts and science faculties, (less so in the social science faculty) and first and later-born children being over-represented in the science and professional subjects faculties. In the next section of this paper we want to go on to look at the interaction of birth order, faculty and the reporting of illness.
(b) Znteracrion between variables 1. Faculty, birth order and illness. In Table 6, we look at the percentage reporting illness by facuhy and birth order position (in this, and in the subsequent table, we looked only at the reported incidence
Psychosomatic
illness, birth order and intellectual preference-l.
Men
41
TABLE K-BIRTH ORDERBYFACULTY ( %AGES)
First Arts
Born
Later
Born
Only
‘Other
20.1
18.0
24.5
23.8
Only’*
Tvin 28.1
17.4
20.6
19.0
21.1
15.6
Professions
26.6
26.2
22.9
25.0
23.4
Science
36.0
35.1
33.6
30.1
32.8
Social
Science
N= 4465.
*See Table 4,footnote
*.
TABLET.--0/d AGE REPORTINGILLNESSBYFACLJL~
AND BIRTHORDERPOSITION
of nervous tension, insomnia, migraine and hay fever-the numbers are too small to allow systematic comparisons for the other illnesses). As the table shows, for nervous tension, arts and social science students tend to report more illness than those studying professional subjects and science. This pattern is supported within the birth order groups, except in the case of only children studying professional subjects, where the frequency of reporting rises, and in the case of “other only” children studying science, where the proportion rises again. Similarly, other only students studying the social sciences tend to report less nervous tension. Similarly the faculty variations do not alter the basic birth order pattern of reporting with only children reporting more illness than first-borns and later-borns. However, “other only? tend to vary somewhat. An essentially Cmilar pattern is revealed for the reporting of insomnia. Arts students report more insomnia than students in other faculties. This pattern is repeated within the birth order groups, except that only children studying professional subjects tend to give relatively frequent reports as do “other onlys” studying the social sciences or science. Also, later-born social scientists tend to report a relatively high amount of insomnia. Within faculties, once again, we find the birth order pattern of only children reporting more than later-borns and first-borns supported. “Other onlys” tend to report a fairly high incidence of insomnia, but there are variations for this birth order group. In the case of migraine we find that the incidence of reporting follows a somewhat different pattern, the faculties with students in the arts and professional subjects reporting more than those studying social science, with scientists falling in the middle. This pattern is supported within the birth order groups, except that both only and “other only” social science students tend to report more migraine than others. Within the faculties the birth order pattern of only children reporting more than laterborns and first-borns is not clear, although “other only? report least of all. These differences are found within faculties, except that “other onlys” tend to give low reports in the social science faculty and only children give relatively high reports in this faculty. Finally in the case of hay fever we find, once again, that the arts students report a high amount of hay fever, but in this case they are joined by students reading science and professional subjects, and all these report more than social science students. Within the various birth order groups we find that there is reasonable support for these faculty differences but only child students in the social sciences give high reports and only children in the arts give low reports; also, “other only” children in science and the professional subjects tend to give relatively low reports. Within the faculties the overall birth
N = 3757.
Later Born
First Born
0.0
3.2
1
27.1
4
9.1
6.6
4.5
8.2
15.9
1
2
15.0
6
19.4
13.0
40.5 23.4
4
14;l
'5
9.4 13.8
3
6.8
6.9
11.8
6
10.3
19.0
2.7
7.7
18.9
6.3
8.8
3.8
10.4
4.6 '10.6
5.9
10.6
0.0
20.0
11.1
11.1
0.0
30.8
0.0
5
7.3
10.8 14.7
6.0
6.6
9.1
3
8.8
12.8
2
27.3
46.2 15.4
0.0
5.3 14.3
21.1
1
6
5
4
2
19.4
7.3
7.4
8.0
6.6
0.0
8.3
0.0
4.1
tFigures
9.1
10.0
6.4
12.5
4.0
4.0
1.8
5.9
11.9
5.9
3.4
5.0
6.6
0.0
6.7
7.7
0.0
11.0
7.0
9.9
7.5
8.2 8.5
6.5
12.5
6.2
10.3
4.9
6.1
9.7
3.5
8.8
18.2
7.7
2.0
7.7
11.1
5.3 0.0
6.5 0.0
5.6
8.8
6.0
0.0
7.4
2.6
Migraine HOT Fever
ONLY)?.
10.6
7.5
2.7
4.0
9.8
8.8
6.0
3.3
0."
15.4
0.0
0.0
7.7
14.3
6.3
0.0
6.5
5.0
8.5
9.7
8.1
9.0
8.0
12.5
14.3
2.9
5.7
3.0
7.5
4.7
9.8
4.8
5.4
6.1
2.4
9.9
5.9
0.0
6.7 11.1
5.6
0.0
0.0
5.3
2.u
0.0
7.7
0.0
9.1
9.1
0.0
11.1
4.8
4.0
4.2
14.3
13.2
23.2
13.6
25.0
23.1
11.5
18.7
27.3
30.8
15.8
31.6
22.2
17.6
14.8
23.3
12.8
13.9
20.3
12.0
4.9
19.4
14.0
13.1
18.2
23.1
18.2
28.6
15.4
14.3
31.3
30.0
15.0
25.5
13.9
16.2
18.8
13.4
35.3
21.4
22.1
16.1
14.9
14.2
11.1
20.0
30.8
15.0
9.1
18.2
33.3
22.2
33.3
28.0
29.2
13.4
21.0
14.1
16.2
20.0
12.0
18.3
16.4
7.7
5.6
22.2
9.7
23.7
16.0
20.7
33.3
Aits soc sci ~rof Sciencearts soc Sci ~rof Science
6.9
6.5
Science
ANDBIRTHORDERPOSITION(UNDERGRADUATES
are only given where a box contains at least 10 cases.
19.0 23.4
11.3 10.0
13.4
9.1' 5.3
16.7
10.8
5.1
8.8
0.0
15.4
15.8
0.0 14.3
14.3 11.8
36.4
7.7
7.1
0.0
12.0
27.3
5.6
14.1
0.0 0.0
6
11.8
20.0 11.1
8.3
8.0 10.5
19.0
10.3
25.0
5.6 23.1
8.0
8.3
Insomnia Sot Sci Prof
5
32.4 14.3
0.0
4
18.5
3
13.3
1
2
Nervous Tension Sot Sci Prof Science Arts
REPORTING ILLNESS BYYEAR
*See Table 4, footnote*.
'Other Only''3
Only Children
Arts
Year
TABLE 7.-_% AGE
95
9
h- 47
x-288
N-375
N-403
N=48?
!P ib
Ic=42
EI=*iL
N=34>
x=371
h=4li,
N=
N= 50
I\'= 57
X- 68
f;=63
N= 11
N= 12
s=13ii
N-119
Ii-91
N-
h
Psychosomatic
illness, birth order and intellectual
preference-I.
Men
43
order pattern of first and later-borns reporting less than onlys and “other only? is again given reasonable support. 2. Faculty, birth order, year and illness. Finally, in Table I we look at the reporting of illness by birth order and year (in this case looking at undergraduates only). From the results reported in Table 3 we suggested that nervous tension and insomnia might be regarded as “stress related” illness, migraine as intermediate and hay fever as showing no simple relationship to stress (at least as indicated by increasing course demands). In the case of nervous tension and insomnia, then, there is an overall increase year by year in reporting. When we look within the birth order groups we find that this is supported for only, other only and first-borns, although in all these cases there is a slight tendency for the reporting of illness to drop in the later years. In the case of later-borns we find there is a tendency for reports to drop and rise again in the middle years. In the case of migraine where the overall pattern is one of a rise in the reporting of illness, also, we find that the birth order groups all tend to support this pattern with only children and other only children tending to report less in the later years. Finally, in looking at hay fever, we find once more, for the overall pattern-which is a tendency to report more hay fever in the middle years of the course except for arts students who tend to rise all the way through-all the birth order groups tend to support the distribution. However only child scientists tend to report least in the middle years, first-born students studying professional subjects tend to rise all the way through and later-born arts and science students show a somewhat less clear-cut pattern. CONCLUSION
The data we have collected in this survey of reported illness in students is complex. Nonetheless there are a number of findings which emerge from this preliminary analysis. If we look at our major variables, it is clear that arts students tend to report more illness than students in the sciences, along with students reading professional subjects who also tend to report a relatively low incidence of most illnesses, and students in the social sciences fall somewhat in the middle. This finding is particularly clear in the case of those illnesses which apparently show a fairly straightforward relationship to stress, as indicated by increasing course demands: i.e. nervous tension, nervous exhaustion, insomnia, and migraine. Similarly, and again with particular reference to this set of “stress related” illnesses, we find that “only children” tend to report more illnesses than first-borns and later-borns. The reporting of illness by “other only” children-those with a large gap between themselves and their siblingstends to be more variable in comparison with these other groups, however. These findings suggest that a greater incidence of various illnesses is reported by students whose intellectual preference lies in areas concerned with expression and communication and, equally, students whose birth position is one where they may have been more reliant on communication with adults. These findings are supported when we look at the results in a more detailed fashion and examine variations within the faculties, within birth order groups and within years. They suggest that an expressive or adult-oriented approach is influential in shaping the reporting of illness: these data cannot tell us, of course, whether or not students in the other groups are equally susceptible to the illnesses that we have surveyed but tend to repress them, or if they are, in fact, less common. In a second paper we hope to describe the comparable data that was collected for the women students in the sample, and in subsequent papers we will go on to look at inter-relations between illness, and other influences on the reporting of illness. REFERENCES 1. HUDSON L. Contrary Imaginations. Methuen. London (1966). 2. AUSTINM. D. Dream re& and the bias of intellectual ability. Nature, Vol. 231 pp. 59-60 (1971). 3. HOLMES M. A. M. REM sleep patterning and dream recall in convergers and divergers: Evidence for different defensive preferences. Occasional Paper 16, Centre for Research in the Educational Sciences, University of Edinburgh (1973).
44
PETERSHELDRAKE,MARGARETCORMACKAND JAMESMCGUIRE
4. SHELDRAKEP. and CORMACKM. Dream recall and the menstrual cycle. .I. Psychosom. Res. 18, 347 (1974). 5. HUDSONL., JACOBB. and SHELDRAKE P. Lieben und Arbeiten: Patterns of marriage and patterns of work. Occasional Paper 12, Centre for Research in the Educational Sciences, University of Edinburgh (1973). 6. HUDSONL. Fertility in the arts and sciences. Sci. Studies 3, 305-308 (1973). 7. KAFVR R. L. Student wastage: An epidemiological inquiry into psychiatric and allied factors contributing to it. Unpublished Doctorial Dissertation, University of Edinburgh (1964). 8. KIDD C. B. Epidemiological factors in mental illness: Psychiatric morbidity among students. Unpublished Doctoral Dissertation, University of Edinburgh (1963). 9. RYLE A. Student Casualties. Allen Lane and The Penguin Press, London (1973). 10. SCH~~LERC. Birth order and hospitalisation for schizophrenia. J. Abnorm. Social Psychol. 69, 574 (1964). 11. CHEN F. and COBBS. Family structure in relation to health and disease. J. Cl~ron. Dis. 12, 544 (1960). 12. ERLENMEYER-KIMLING L., VAN DEN BOSCHE. and DENHAMB. The problem of birth order and schizophrenia: A negative conclusion. Brit. J. Psych&. 115, 659 (1969). 13. SCXI~LER C. Birth order effects: Not here, not now! Psychol. Bull. 78, 161 (1972). 14. WEISS J. H. Birth order and asthma in children. J. Psychosom. Res. 12, 137 (1968). 15. SCPACHTERS. Birth order, eminence and higher education. Am. Sociological Rev. 28, 757 (1963). 16. ALTUS W. D. Birth order and its sequence. Science 151, 44 (1966). 17. HUDSONL. Frames of Mind. Methuen, London (1968). 18. SULLOWAYF. and MCGUIRE J. Birth order and cognitive style, to be published (1976).
