International Journal of Speech-Language Pathology

ISSN: 1754-9507 (Print) 1754-9515 (Online) Journal homepage: http://www.tandfonline.com/loi/iasl20

The assessment for living with aphasia: Reliability and construct validity Nina Simmons-Mackie, Aura Kagan, J. Charles Victor, Alex Carling-Rowland, Ada Mok, Jeffrey S. Hoch, Maria Huijbregts & David L. Streiner To cite this article: Nina Simmons-Mackie, Aura Kagan, J. Charles Victor, Alex Carling-Rowland, Ada Mok, Jeffrey S. Hoch, Maria Huijbregts & David L. Streiner (2014) The assessment for living with aphasia: Reliability and construct validity, International Journal of Speech-Language Pathology, 16:1, 82-94 To link to this article: http://dx.doi.org/10.3109/17549507.2013.831484

Published online: 25 Oct 2013.

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Date: 04 November 2015, At: 00:11

International Journal of Speech-Language Pathology, 2014; 16(1): 82–94

ORIGINAL RESEARCH: GENERAL ARTICLE

The assessment for living with aphasia: Reliability and construct validity

NINA SIMMONS-MACKIE1, AURA KAGAN2, J. CHARLES VICTOR3, ALEX CARLING-ROWLAND4, ADA MOK2, JEFFREY S. HOCH5,6,7, MARIA HUIJBREGTS7,8 & DAVID L. STREINER7,9

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1Southeastern

Louisiana University, Hammond, LA, USA, 2Aphasia Institute, Toronto, Canada, 3Institute for Clinical Evaluative Sciences, Toronto, Canada, 4College of Audiologists and Speech Language Pathologists of Ontario, Canada, 5Keenan Research Centre, Li Ka Shing Knowledge Institute, Toronto, Canada, 6Cancer Care Ontario, Toronto, Canada, 7University of Toronto, Toronto, Canada, 8Kunin Lunenfield Applied Research Unit, Baycrest, Toronto, Canada, and 9McMaster University, Ontario, Canada

Abstract The Assessment for Living with Aphasia (ALA) is a pictographic, self-report measure of aphasia-related quality-of-life. Research was undertaken to assess test–re-test reliability, construct validity, and the ability to discriminate aphasia severity. The ALA was administered to 101 participants with aphasia on two occasions. Test–re-test reliability was evaluated using intra-class correlations and internal consistency using Cronbach’s alpha. Three reference measures were administered to assess construct validity. A focus group reported on ease of administration and face validity. Analysis identified 15 out of 52 rated items for elimination. For the remaining items, test–re-test reliability was excellent for the total score (ICC ⫽ .86) and moderate-to-strong for a priori domains adapted from the WHO ICF (.68–.83). Internal consistency was acceptableto-high. Significant correlations were observed between the ALA and reference tests (SAQOL-39, .72; p ⬍ .001; VASES, .62, p ⫽ .03; BOSS CAPD, ⫺.69; p ⫽ .008). The language impairment domain discriminated between all aphasia severity groups, while mild aphasia was different from moderate and severe aphasia in participation and total scores. The ALA was reportedly easy to administer and captured key aspects of the experience of living with aphasia. Results suggest acceptable test–re-test reliability, internal consistency and construct validity of the ALA.

Keywords: Aphasia, quality-of-life, assessment, outcome, stroke, communication disorders.

Introduction In 1948 the World Health Organization (WHO) defined health as “a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity” (WHO, 1948). Since that time the medical field has slowly moved in the direction of a more holistic focus on the individual and his or her life context, as opposed to a narrow focus on disease or disorder (e.g., Hayes & Hodson, 2011; Joint Commission, 2010; Mezzich, 2011). In the communication disorders literature this movement is reflected in an interest in quality-of-life (QoL) and well-being. For example, Speech Pathology Australia (SPA) and the American Speech-Language-Hearing Association (ASHA) have included quality-of-life in the scope of speech-language pathology practice (ASHA, 2001; SPA, 2003). Research has recognized areas associated with quality-of-life after the onset

of aphasia. For example, Cruice Worrall, Hickson, and Murison (2003) and Cruice, Hill, Worrall, and Hickson (2010) identified factors such as engaging in meaningful activities, socializing with others, and having a positive outlook as aspects of QoL in aphasia. Additionally, there is increased awareness that improvements in a clinical setting do not necessarily result in improvements in daily life situations or life satisfaction; thus, there has been a call for interventions that positively and directly affect life quality (Cruice et al., 2003, 2005; Holland & Thompson, 1998; Kagan & LeBlanc, 2002; LaPointe, 1999; LPAA Project Group, 2000; Ross, 2005; Ross & Wertz, 2003; Sarno, 2004; Simmons-Mackie, 2000, 2008; Worrall & Holland, 2003). In order to devise interventions that address QoL, clinicians must understand the impact of communication difficulties on the daily lives of clients with aphasia.

Correspondence: Nina Simmons-Mackie, 580 Northwoods Drive, Abita Springs, LA 70420, USA. Email: [email protected] ISSN 1754-9507 print/ISSN 1754-9515 online © 2014 The Speech Pathology Association of Australia Limited Published by Informa UK, Ltd. DOI: 10.3109/17549507.2013.831484

Assessment for living with aphasia

Assessment tools are needed to identify and quantify life quality issues and help establish relevant and meaningful goals (Cruice et al., 2003; Dalemans, de Witte, Lemmens, van den Heuvel, & Wade, 2008; Doyle, 2005; Doyle, Mikolic, Prieto, Hula, Lustig, Ross, et al., 2004; Engell, Hütter, Wilmes, & Huber 2003; Hilari, Byng, Lamping, & Smith, 2003; Ross & Wertz, 2003).

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Quality-of-life measures Quality-of-life measures have been developed for general use (e.g., WHOQoL, WHO, 1998). However, general QoL tools sample different health outcomes and many of these fail to capture the potential treatment outcomes associated with the consequences of aphasia. Several tools have been developed explicitly to measure QoL and/or wellbeing of individuals with stroke or aphasia (Doyle et al., 2004; Engell et al., 2003; Hilari et al., 2003; Paul, Frattali, Holland, Thompson, Caperton, & Slater, 2005; Swinburn & Byng, 2006), but these available tools are either lengthy, communicatively inaccessible for severe aphasia, focused on stroke rather than aphasia, or have yet to be subjected to sufficient psychometric testing for widespread use. Consequently, QoL is rarely formally evaluated among people with aphasia (Simmons-Mackie, Threats, & Kagan, 2005).

Development of the Assessment for Living with Aphasia The Assessment for Living with Aphasia (ALA) (Kagan, Simmons-Mackie, Victor, Carling-Rowland, Hoch, Huijbregts, et al., 2011) was developed in order to address the need for a communicatively accessible, psychometrically sound, aphasia-related QoL measure. It is a pictographic, self-report measure designed to measure outcomes associated with the impact of aphasia on daily life. Conceptual framework of the ALA. The ALA is based on Living with Aphasia: Framework for Outcome Measurement (A-FROM) (Kagan, SimmonsMackie, Rowland, Huijbregts, Shumway, McEwen, et al., 2008). A-FROM is a user-friendly framework designed to guide and organize thinking related to life with aphasia. A-FROM is adapted from the World Health Organization International Classification of Functioning, Disability, and Health (ICF) (WHO, 2001). The ICF defines health in terms of Body Structure and Function, Activities and Participation, and Personal and Environmental Factors. Body Functions include the physiological and mental functions of the body, while body structures refer to anatomical elements such as limbs or muscles. Activities refer to particular actions or tasks performed by a person. Participation refers to involvement in personally relevant life situations. In

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addition, the ICF recognizes the influence of the external environment including barriers and facilitators that exist outside of the person (environmental factors), as well as intrinsic factors such as gender, culture, or age (personal factors). The A-FROM adaptation of the ICF is useful for understanding the impact of aphasia at a variety of levels and serves as the scaffold upon which the ALA was designed (Simmons-Mackie & Kagan, 2007). A-FROM ties the ALA to the conceptual underpinnings of the ICF and includes the key domains of ICF in a simplified schematic (Figure 1). In A-FROM, body function is represented as language and related impairments, environment focuses on the communication environment, and the participation domain (relationships, roles, and activities of choice) includes what the ICF calls activities. In addition, the definition of personal factors is expanded to explicitly include psychosocial aspects such as identity or self-esteem. Unlike the ICF, A-FROM includes QoL as a dynamic overlap of domains for people affected by aphasia. Development of A-FROM is grounded in the literature, the ICF, extensive experience in working with people affected by aphasia, and, most important, the needs and opinions expressed in multiple focus groups by various stakeholders (as described in Kagan et al., 2008). Questions on the ALA were designed to address the A-FROM adapted ICF domains of language impairment, participation, personal factors, and environmental factors within a dynamic interaction referred to as “living with aphasia”. Self-report rating. One of the earliest decisions in developing the ALA was to provide a means for people with aphasia to report their own perspectives on their lives. QoL is a highly subjective concept and most agree that individuals should be the primary informants regarding their own life quality (WHO, 1998). In a discussion of self-report measures, Doyle, McNeil, Hula, and Mikolic (2003, p. 292) suggest that “it appears that patient report measures of health status and SWB [subjective well-being] provide unique and important information not addressed by other kinds of assessments”. However, there are potential drawbacks to self-report measures (Newell, Girgis, Sanson-Fisher, & Savolained, 1999). For example, some respondents might encounter difficulty in comprehending the intent of questions or answering questions (Dalemans, Wade, van den Heuvel, & de Witte, 2009). In one study, ∼ 25% of stroke survivors were excluded from QoL assessment because of aphasia or cognitive impairments (Kwa, Limburg, & de Haan, 1996). For this reason, there is support for proxy judgements in which another person reports for the person with communication disability (Hilari & Byng, 2009; Hilari, Owen, & Farrelly, 2007). However, most caution against proxy judgements on personal or subjective domains (e.g., Carod-Artal, Coral, Trizzoto, & Moreira, 2009).

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N. Simmons-Mackie et al.

Figure 1. Living with Aphasia: Framework for Outcome Measurement (A-FROM) (reprinted with permission of the Aphasia Institute, Toronto, Canada).

There is evidence that people with aphasia, even severe aphasia, can report their own perspectives if given appropriate communicative support (Engell et al., 2003; Kagan et al., 2008; Luck & Rose, 2007). There is a growing literature describing methods of increasing communicative access for people with aphasia (e.g., Alarcon & Rogers, 2010; Kagan, Black, Duchan, Simmons-Mackie, & Square, 2001; Simmons-Mackie, Kagan, O’Neill Christie, Huijbregts, McEwen, & Willems, 2007). For example, characteristics of aphasia-friendly printed materials and supports have been described (e.g., Hilari & Byng, 2001; Kagan, 1998; Rose, Worrall, & McKenna, 2003; Worrall, Rose, Howe, Brennan, Egan, Oxenham, et al., 2005). The ALA was designed with these principles in mind and in keeping with extensive experience in Supported Conversation for Adults with Aphasia (SCATM), a method designed to facilitate communication with people with aphasia (Kagan, 1998). Furthermore, the intent of the ALA was to capture each person’s subjective perceptions of life, a necessary element in devising person-centred goals. The ALA was not envisioned as a test of clinicianrated language performance. Therefore, self-report was deemed appropriate for capturing the subjective life experiences of people with aphasia. Question/scale development. A large pool of self-report questions related to living with aphasia were created over a 2-year period based on the literature, research team experience, and input from stakeholders,

including individuals with varying degrees of aphasia, their families, and speech-language pathologists (SLPs). As items were developed, they were examined by the authors and others who volunteered to help (21 SLPs; 24 people with aphasia). Examiners were asked to try out questions to determine ease of answering and relevance, and were encouraged to suggest alternative wording, add questions, and provide feedback. In addition, the researchers and SLP volunteers made determinations regarding the fit of items with relevant A-FROM domains. These findings, including the various iterations of the question pool, were documented in methodological notes that were maintained throughout the project. The process resulted in a total of 57 questions including 52 items that were scaled. Of the 52 scaled questions, there were 23 items in the participation domain, five in the language domain, nine in the environment domain, 13 in the personal domain, and two general questions about quality-of-life with aphasia (see Table I). In addition there were five items designed to provide descriptive information. These descriptive or frequency questions (e.g., how many days a week do you get out?) did not elicit ratings and were not included in the scores; rather, they were provided to orient the client to the specific content of following questions and create a context for interpreting ratings. An optional probe question was also included for use when a rating was negative in order to determine whether it was aphasia that contributed to this negative rating or some other cause.

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Table I. Abbreviated content of the 52 rated questions of the ALA followed by the five descriptive or frequency questions. Note that this is not the actual wording of questions since questions are presented in a conversational script form. Domains Language

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Participation

Environment

Personal

Question #

Key content of Question

2 3 4 5 6 1 8 10 11 12 13 14 15 16 17 18 19 20 22 23 24 25 26 27 28 29 30 31 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55

Talking Understanding Reading Writing Aphasia overall Knowledge of aphasia Getting out to the places you want to go Getting out the number of days you want Doing what you want at home Doing what you want regarding work or volunteering Doing what you want regarding finances & money Doing what you want regarding leisure and recreation Doing what you want regarding learning new things Getting the information that you need Getting around like you want (transport) Performing your roles & responsibilities as you want Your relationship with (name of key person) Having conversations like you want As many relationships and friends as you want Joining in simple conversations Joining in complicated conversations Joining in conversation with other people with aphasia Joining in conversations at home Joining in conversations in the community Forgetting about your aphasia in an aphasia group Forgetting about your aphasia at home Forgetting about your aphasia when out in the community Aphasia getting in the way of doing what you want Getting help from others in an aphasia group Getting help from others at home Getting help from others in the community Feeling comfortable talking in an aphasia group Talking at home (supported) Talking in the community (supported) Knowing you are competent (other people with aphasia) Others know you are competent (people at home) Others know you are competent (people in community) In charge of your life (autonomy) Proud Confident Respected Accepted Lonely Depressed Frustrated Angry Think good things about yourself Overall how do you feel Things you enjoy and look forward to Life in the future

56 57

Overall, does aphasia get in the way Which one is you? (pictograph of moving on with life)

7 9 21 32 33

Number Number Number Number Number

Moving on with life question

Descriptive items (not included in the ALA scoring)

As questions were developed, corresponding pictographic support material was created along with a conversational script. The clinician script and pictographic support (see Figure 2) were

of of of of of

places you go in a week days of week that you get out people you talk to in a week things you do to help you communicate things other people do to help you communicate

developed to enable more accurate self-report for people with severe as well as mild and moderate aphasia. The script was also designed to promote consistent administration of questions and client

N. Simmons-Mackie et al.

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Figure 2. Example of pictographic support included in the Assessment for Living with Aphasia (ALA). Each is an example of a page seen by the client with aphasia during the administration of the ALA (reprinted with permission of the Aphasia Institute, Toronto, CA).

comprehension and to facilitate a conversational feel to the assessment. Rating scale. Questions on the ALA were answered by identifying points on a 9-point, 0–4 rating scale (with .5 point intervals). Zero (0) represented negative anchors such as never or definitely no, and 4 represented positive anchors such as always or

definitely yes. The 0–4 scale was chosen to maintain consistency with the ICF which uses a 0–4 rating to quantify the extent of problems associated with each of the sub-categories defined in the ICF system (WHO, 2001). Ratings obtained on the ALA were summed for questions in each conceptual domain (participation, language impairment, personal factors, environment), and the overall total score

Assessment for living with aphasia

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included the sum of the domain ratings and a general “moving on with life” question. Pilot trials. A total of six pilot trials including 48 individuals with aphasia and five SLPs were carried out over a 15-month period to refine the ALA questions and rating scales. Each pilot trial involved one or more administrations of the ALA to a group of participants with aphasia by an experienced SLP. During these trials feedback and face validity information was obtained through interviews with SLPs and people with aphasia. In addition, preliminary data regarding reliability (intra-class correlations) and internal consistency (Cronbach’s alpha) were obtained. Based on results of each trial, questions were modified, rating scales were refined, and support materials were revised. The result of question development and pilot trials was the version of the ALA used in the psychometric evaluation reported below. In order to evaluate the ALA, the following questions were asked: Is the ALA a reliable tool for assessing people with aphasia as measured on test– re-test? Is patient-reported QoL as assessed on the ALA valid as measured by correlation with other QoL measures and focus group feedback? Does the ALA discriminate between people with aphasia of varying severity? Method Participants: Speech-language pathologists Three SLPs administered all tests. Their aphasia experience ranged from 2–20 years. All were trained in conversation support (i.e., Supported Conversation for Adults with Aphasia SCA™, Kagan, 1998) and all participated in ∼ 10 hours of preparation specific to the research protocol (e.g., administration of reference measures such as the Stroke and Aphasia Quality of Life Scale-39). Participants: People with aphasia Potential participants with aphasia were recruited from outpatient facilities. All referred individuals who met inclusion criteria and consented to participate were enrolled. Inclusion criteria included: diagnosis of aphasia, hearing and vision sufficient to participate, ⱖ 18 years of age, at least 6 months postonset, not currently receiving speech-language therapy and the ability to complete the assessment in English. Diagnosis of aphasia was made by referring SLPs based on clinical observation as well as administration of the Western Aphasia Battery (WAB) (Kertesz, 1982). Diagnosis was confirmed by research SLPs. Individuals with co-existing dementia were excluded. Institutional review board approval was obtained from all participating facilities, and procedures complied with ethical guidelines for protection of human subjects.

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Sample size. Sample size calculations were performed to power the construct validity or correlation analyses using sample size formulae derived from Fisher’s normalizing transformation (Fisher, 1926). Assuming a two-tailed type I error rate of .05, power of 80%, and an absolute difference between the null and alternative correlation coefficient of .25, 75 participants would be required. The sample size of 75 also provided a confidence interval half-width around an intra-class correlation coefficient (ICC) estimate of between .05–.10 depending on the size of the ICC estimate (Bonnett, 2002). Given the nature of the population being sampled, a liberal loss-to-follow-up rate of 25% was assumed; thus, a recruitment target was set at 100 individuals. A total of 142 people with aphasia were approached; 39 of these recruits declined to participate and two participants dropped out early in testing, resulting in 101 participants who completed the study. Table II provides characteristics of participants with aphasia.

Procedures: Data collection The ALA was administered in healthcare facilities, aphasia community centres, or the participant’s home, depending on participant preference. Assessment occurred on two occasions for each participant separated by ∼ 2 weeks. The SLP who administered the ALA at time 1 also administered the ALA at time 2. At the time of the first administration four additional measures were completed. At the time of the second assessment, only the ALA was administered. All administrations were conducted face-to-face. In addition to recording responses to all test items, SLPs documented timing and relevant observations. Video recorded samples of ALA administration were reviewed by a research team member to assess fidelity of ALA administration; all SLPs conformed to pre-determined accuracy criteria. In addition to the ALA, measures administered at assessment time 1 included the CommunicationAssociated Psychological Distress Scale of the Burden of Stroke Scale (BOSS CAPD) (Doyle et al., 2004), the Visual Analogue Self-Esteem Scale (VASES) (Brumfitt & Sheeran, 1999), the Stroke and Aphasia Quality of Life Scale-39 (SAQOL-39) (Hilari et al., 2003), and the severity scale of the Boston Diagnostic Aphasia Examination (BDAE) (Goodglass & Kaplan, 1983). Order of administration of the BOSS CAPD, VASES, SAQOL-39, and ALA was randomized for each participant. The BDAE severity scale, a clinician rated 0–5 scale ranging from no usable speech to minimal discernible communication disability, was completed after the other measures. For each participant, the research SLP completed the BDAE severity ratings at the conclusion of testing after they were familiar with the participant’s communication performance.

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N. Simmons-Mackie et al. Table II. Characteristics of participants with aphasia.

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Variable Gender (n ⫽ 101) Age in years (n ⫽ 101) Ethnicity (n ⫽ 90) Asian Black White Other Marital status (n ⫽ 99) Aetiology (n ⫽ 100) Stroke Trauma Other Months post-onset (n ⫽ 100) WAB AQ (n ⫽ 99) Aphasia type (n ⫽ 99) Broca’s Global Anomic Wenicke’s Conduction Transcortical sensory Estimate of aphasia severity (n ⫽ 101) BDAE severity rating Co-existing disorders (n ⫽ 101) Motor speech disorders Hemiplegia/paresis Hemi-neglect Visual impairment (uncorrected)

Number/score

Mild 9

Female 44 Mean (SD): 64.59 (11.88)

Male 57 Range: 26–87 years

6 2 77 5 Married 73

Single 26

86 5 9 Mean (SD): 76.87 (73.90) Mean (SD): 69.11 (24.52)

Range: 6–440 Range: 6.6–99

29 5 44 7 13 1 Moderate 57 Mean (SD): 3.13 (1.18)

Severe 35

40 56 4 18

WAB, AQ: Western Aphasia Battery Aphasia Quotient (Kertesz, 1982); BDAE, Boston Diagnostic Aphasia Examination (Goodglass, & Kaplan, 1983).

The BOSS CAPD, VASES, and SAQOL-39 were chosen to assess construct validity since each contains elements relevant to QoL. The BOSS CAPD is a short, three-question scale that measures the psychological impact of stroke-induced communication disability. On a 5-point scale the client rates the frequency that he/she experiences a particular construct (e.g., dissatisfied with life). The VASES consists of line drawings illustrating bipolar constructs (e.g., angry–not angry) and a 5-point rating scale to indicate how people view themselves in relationship to the construct. The SAQOL-39 is a comprehensive, health-related QoL measure designed for and validated on people with aphasia (Hilari, Lamping, Smith, Northcott, Lamb, & Marshall, 2009). The SAQOL-39 consists of 39 orally-presented questions addressing activities of daily living (e.g., preparing food), physical function (e.g., walking), communication (e.g., finding a word), psychosocial function (e.g., withdrawn), and energy (e.g., tired). People with aphasia respond by rating responses on a 1–5 scale (e.g., definitely yes–definitely no; could not do at all–no trouble at all). Upon completion of all test administrations a focus group of the three SLP assessors was held to explore experiences administering the ALA and other measures. This focus group was designed to access information regarding face validity, ease of administration, adverse effects, satisfaction with the

measures, and subjective impressions regarding difficulty for specific participant sub-groups. Procedures: Data analysis A qualitative analysis of themes from the research SLP focus group was completed to identify key features of experiences administering the ALA and to gain an impression of face validity of the ALA. In order to conduct this qualitative analysis, the audio recorded focus group was orthographically transcribed and thematic content was analysed (Spradley, 1980). A preliminary individual item analysis of all scored ALA questions was conducted including descriptive statistics (mean, median), test–re-test reliability of individual items (intra-class correlation), and consideration of focus group feedback. As part of this analysis, the polytomously scored ALA items were evaluated against criteria for adequate functioning of Likert-type scales and were collapsed as necessary. The operative criteria for each item/question were: ⱖ 10 responses for each point on the 9-point rating scale and a unimodal distribution of responses across categories (Linacre, 2004). A traditional psychometric evaluation of the ALA following modification based on focus group feedback and individual item analysis (e.g., item removal, re-categorization of Likert scales) was conducted to evaluate reliability and validity.

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Assessment for living with aphasia

Test–re-test reliability was performed for the total score and conceptual domain totals. In addition, item-total correlations and Cronbach’s alpha were calculated to examine internal consistency. Construct validity was evaluated by calculating Pearson’s correlation coefficients for the ALA total score with previously validated measures related to QoL in aphasia. Fisher’s z-transformation of the correlation coefficients followed by a Student’s t-test was used to determine if correlation coefficients were significantly larger than a moderate correlation of .50. Finally, discriminant group analysis was conducted by grouping participants into aphasia severity groups based on their BDAE severity rating (Goodglass & Kaplan, 1983). One-way analysis of variance (ANOVA) followed by Bonferroni corrected post-hoc pairwise comparisons were used to examine differences in ALA scores across aphasia severity groups. All analyses were conducted in SAS v9.2 (Cary, NC) except for evaluating the item responses distribution which was conducted using WINSTEPS 3.73 (Linacre, 2011).

Results Developing the scoring algorithm of the ALA Based on individual item analysis and specific feedback from the SLP focus group regarding face

validity of questions, 15 of the original 52 rated items were identified for removal from further analysis.1 Decisions regarding exclusion of these items depended on poor item test–re-test reliability (ICC ⬍ 0.50) and focus group feedback (see Table III). In addition, one item (# 12) was removed from further analysis due to missing values (see Table IV for a list of these questions). The remaining 37 polytomously-scored items of the ALA were evaluated for adequate functioning. The original 9-point Likert scale (0–4 with .5 intervals) resulted in almost all items failing to meet the criteria outlined for an adequate rating scale. Collapsing each of the scores into a 5-point scale for purposes of analysis (0–.5 → 1; 1–1.5 → 2; 2–2.5 → 3; 3–3.5 → 4; 4 → 5) resulted in an overall ALA score that met criteria for adequate functioning, with four individual questions that had fewer than 10 responses in the lowest category. These four questions were maintained as 5-point scales to facilitate the scoring process. The final ALA scores, after item modifications, were normally distributed (Skewness: ⫺0.05; Kurtosis: ⫺.47; Shapiro-Wilk test for normality W: ⫺.99, p ⫽ .61). The maximum observed score was 180 points out of a possible 185, and the minimum observed score was 86 (minimum possible score 37). At the conclusion of this stage of data analysis, 37 scored ALA questions remained.

Table III. Descriptive statistics on each ALA scored item including the mean score and standard deviation (SD), item median and item test–re-test reliability (intra-class correlation: ICC).

Item # 1 2 3 4 5 6 8 10 11 12a 13 14 15 16b 17 18 19 20 22 23 24 25b,c 26 27 28b,c 29b,c aDeleted

Mean (SD) 3.79 3.06 3.96 3.03 2.62 3.19 3.67 3.90 3.68 3.72 3.39 3.73 3.47 3.24 3.75 3.81 4.25 3.75 3.99 4.00 2.96 4.38 4.10 4.38 3.14 3.12

(.98) (1.05) (.99) (1.33) (1.16) (.88) (1.10) (1.22) (1.18) (1.30) (1.46) (1.05) (1.13) (1.14) (1.34) (.98) (.91) (.98) (1.03) (.95) (1.19) (.65) (.81) (.65) (1.20) (1.16)

Median

Test–re-test (ICC)

Item #

4.0 3.0 4.0 3.0 3.0 3.0 4.0 4.0 4.0 4.0 3.0 4.0 4.0 3.0 4.0 4.0 4.0 4.0 4.0 4.0 3.0 4.0 4.0 4.0 3.0 3.0

.60 .63 .66 .78 .53 .50 .58 .68 .61 .75 .69 .50 .55 .54 .58 .54 .76 .57 .54 .61 .51 .48 .57 .56 .44 .49

30b 31b,c 34c 35b,c 36b 37c 38 39 40b,c 41 42 43 44b,c 45 46 47 48 49 50 51 52 53b 54 55 56c 57

Mean (SD) 2.80 2.54 4.26 3.86 3.28 3.28 4.19 3.48 4.41 4.30 3.26 3.80 3.86 3.88 3.82 4.07 3.44 3.59 3.06 3.52 3.88 3.85 4.05 4.19 1.77 3.85

(1.16) (1.02) (.85) (1.03) (1.10) (1.10) (.88) (1.09) (.80) (.87) (1.09) (1.18) (1.01) (.89) (.85) (.72) (1.12) (1.20) (.97) (.99) (.83) (.90) (.71) (.84) (.91) (.86)

from subsequent analysis due to a large number of missing values. from scoring algorithm due to poor face validity in focus group. cDeleted from scoring algorithm due to poor item test–re-test reliability. bDeleted

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Median

Test–re-test (ICC)

3.0 3.0 4.0 4.0 3.0 3.0 4.0 4.0 5.0 5.0 3.0 4.0 4.0 4.0 4.0 4.0 3.0 4.0 3.0 4.0 4.0 4.0 4.0 4.0 2 4.0

.62 .49 .28 .48 .56 .29 .56 .62 .49 .55 .53 .67 .46 .52 .56 .51 .69 .73 .60 .50 .59 .54 .59 .68 .32 .57

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Table IV. Abbreviated content of items with poor test–re-test reliability, face validity, or missing values. Question # 12* 16 25 28 29 30 31

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34 35* 36* 37 40 44 53 56

Table VI. Test–re-test reliability as measured by intra-class correlations (ICC) (with 95% confidence intervals (CI)) for each ALA domain and total ALA score along with Cronbach’s alpha for internal consistency.

Item content Doing what you want regarding work or volunteering Getting the information that you need Joining in conversation with people with aphasia Forgetting about your aphasia in an aphasia group Forgetting about your aphasia at home Forgetting about your aphasia when out in the community Aphasia getting in the way of doing what you want Getting help from others in an aphasia group Getting help from others at home Getting help from others in the community Feeling comfortable talking in an aphasia group Knowing you are competent (other people with aphasia) Do you feel proud of yourself Overall how do you feel Overall, does aphasia get in the way

*Note: Item 12 was not included in psychometric evaluation due to missing values; but the question was subsequently revised, tested, and included in the published version of the ALA. Items 35 and 36 are retained in the published ALA to facilitate the conversational flow and context, but are not included in the scoring algorithm due to poor reliability.

Evaluation of ALA ALA domain correlations with total scores. To evaluate whether a total ALA score would be informative, consistent and non-redundant, correlations between domain scores and ALA total score were conducted. Correlations between each a priori domain and the total ALA score ranged from a low of .69 to a high of .87 (Table V). Thus, the four a priori domains correlated highly with the total score (Participation, Personal Factors, Language, and Environment in order of level of correlation), while the singular question representing moving on with life was only moderately correlated (r ⫽ .43). The correlations suggest that the total ALA score is reflective of the overall quality-of-life of people with aphasia, in particular their participation and personal factors. Test–re-test reliability and internal consistency. Test– re-test reliability was excellent for the ALA total score (ICC ⫽ .86). Furthermore, individual domains demonstrated moderate-to-strong test–re-test reliability ranging from .68–.83 (see Table VI); reliability Table V. Correlation (Pearson’s) between domain scores and total ALA score.

Domain Language Participation Environment Personal Moving on with life

Correlation with ALA total score .722 .942 .691 .868 .425

ICC (95% CI) Language Participation Environment Personal Moving on with life Total

.712 .834 .681 .800 .568 .857

(.605, .799) (.763, .885) (.560, .773) (.707, .855) (.420, .687) (.796, .902)

Cronbach’s Alpha .592 .862 .720 .891 – .812

of the moving on with life question was .57. The lower 95% confidence bound was .68 for the four a priori domains and .42 for the moving on with life question, suggesting acceptable test–re-test reliability. In addition, internal consistency of the domains as measured by Cronbach’s alpha was acceptableto-high for all domains and the total score. Construct validity. A statistically significant and moderately strong positive correlation was observed between the ALA total score and the SAQOL-39 (.72) and VASES (.62) (Table VII). A significant negative correlation was found with the BOSS CAPD (⫺.69). Each of these correlations was significantly greater than a moderate correlation of .50 (p ⫽ .032 or less). The negative direction of correlation with the BOSS CAPD relates to the difference in the direction of the rating scales (5 on the CAPD is negative, while 4 on the ALA is positive). Discriminant group analysis. Although all dimensions of the ALA contribute to accurate characterization of aphasia-related QoL, we hypothesized that certain domains would more powerfully discriminate between people with aphasia of varying severity. Discriminant group analyses were conducted to determine if the ALA scores would discriminate aphasia severity sub-groups, as measured on the BDAE severity rating (Goodglass & Kaplan, 1983). Participants with aphasia were classified into mild, moderate, and severe groups based on scores. The p-values in Table VIII demonstrate a significant difference (p ⬍ .05) in the severity of aphasia for language, participation, and personal domains as well as for the total ALA score. Bonferroni corrected Table VII. Correlation (Pearson’s) of ALA total score with three reference measures.

Reference measure SAQOL-39 VASES BOSS CAPD

Pearson’s correlation coefficient with ALA total score .721 .617 ⫺.689

p-value* ⬍.001 .032 .008

*Test for difference in absolute correlation from a null value of moderate correlation (.50).

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Table VIII. Discriminant group analyses conducted with one-way analysis of variance (ANOVA) followed by Bonferroni correction using ALA scores and BDAE severity ratings grouped into mild, moderate, and severe aphasia.

ALA

Overall (n ⫽ 101) Mean (SD)

BDAE Mild (5⫹) (n ⫽ 9) Mean (SD)*

Language Participation Environment Personal Moving on Total

15.9 59.6 15.2 41.2 3.9 135.8

19.7 68.9 16.9 45.9 4.1 155.4

(3.3) (10.2) (2.9) (7.1) (.9) (20.6)

(2.6)a (7.7)a (2.2)a (5.3)a (.9)a (16.1)a

BDAE Moderate (3–4) (n ⫽ 57) Mean (SD)* 16.2 59.1 15.2 40.0 3.8 134.3

(3.0)b (9.5)b (2.9)a (6.7)b (.8)a (18.8)b

BDAE Severe (1–2) (n ⫽ 35) Mean (SD)* 14.3 58.1 14.8 42.0 3.9 133.1

(3.2)c (10.9)b (2.9)a (7.9)a,b (1.0)a (22.2)b

p-value Overall ⬍.001 .014 .154 .048 .639 .009

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BDAE, Boston Diagnostic Aphasia Examination (Goodglass & Kaplan, 1983). *a,b,cAcross each row if two means have different superscript letters, then they are statistically different from each other at the .05 level after Bonferroni correction.

post-hoc pairwise comparisons were completed to locate the source of differences and revealed that the language impairment domain discriminated between all aphasia severity groups. Mild aphasia was different from moderate and severe aphasia in participation and total scores, and differed from moderate aphasia for the personal domain. ALA total and participation scores did not discriminate between moderate and severe aphasia as measured herein. Nor did ALA scores discriminate between severity levels for the environment domain or moving on with life question. Focus group results Focus group participants felt that the ALA had strong clinical utility, was relatively easy to administer, and provided valuable information not available via other measures. They identified several items with poor face validity (e.g., patients did not seem to fully understand the question) and recommended that these items be removed. Focus group members reported their subjective impressions that the ALA was appropriate for all severity groups. Time taken to complete the ALA The time taken to complete the ALA (prior to eliminating questions) averaged 40 minutes across all participants with a range from 10–95 minutes. The lower extreme (10 minutes) represented an individual with very mild aphasia; while the upper extremes of time represented people with more severe aphasia suggesting that level of severity influences the time it takes to administer the ALA.

across a variety of domains including real life participation, a construct that is rarely measured for people with aphasia (Dalemans et al., 2008). Construct validity Moderate correlations between the ALA and the BOSS CAPD, VASES, and SAQOL-39 suggest that these measures share some common constructs. We did not expect very strong correlations with the comparison measures since the ALA measures unique aspects of QoL. In other words, while all the measures shared some elements of QoL, none of the comparison measures were entirely coherent with the ALA. For example, the BOSS CAPD and the VASES target components of psychosocial state and well-being. The SAQOL-39 includes a variety of content items that are not sampled on the ALA such as energy and physical function, and includes more activity questions vs comprehensive life participation questions typical of the ALA (e.g., SAQOL asks about standing or using the phone vs ALA questions about taking care of responsibilities at home). The tools also differ on rating methods. For example, questions on the SAQOL-39 ask clients to consider the difficulty of performing tasks or roles while the ALA asks clients to consider satisfaction with particular constructs (e.g., relationships). Finally, there are differences in the “aphasia friendliness” of measures, that is, the degree to which language barriers are reduced to allow for participation of people with aphasia, including severe aphasia. For example, the psychometric trial of the SAQOL-39 excluded individuals with severe aphasia and neither the BOSS CAPD nor the SAQOL-39 are delivered in an aphasia friendly pictographic format. Focus group members reported that they found the SAQOL-39 difficult to administer to individuals with moderately severe or severe aphasia.

Discussion The ALA demonstrates acceptable test–re-test reliability, construct validity, and face validity within the scope of this evaluation. It provides a means of capturing individual perceptions of life with aphasia

The total score The overall ALA score is considered to be an estimate of “aphasia-related quality-of-life”. While the

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ALA total score is weighted towards participation as reflected in the number of questions in the participation domain and the high correlation between participation and the total score (.94), all of the ALA domains were, in fact, correlated with the total. The weighting towards participation is conceptually in line with research demonstrating that social relationships and participation in life roles and events are key dimensions of QoL in aphasia (Cruice et al. 2003, 2010; Dijkers, 1997). In fact researchers suggest that in rehabilitation “… participation level outcomes are probably the strongest correlate of subjective QoL, above and beyond activities or impairments” (Eadie, Yorkston, Klasner, Dudgeon, Deitz, Baylor, et al., 2006, p. 317). Since the ALA is a measure of aphasia-related quality-of-life, it focuses on what people do, how they feel, and what goes on around them in everyday life. Unlike “health-related” QoL measures, the ALA does not attempt to identify aspects of illness or physical function. Nor does it attempt to define specific causes of high or low QoL scores. The ALA does not include questions specifically related to physical disability, financial stability, or other factors that can affect an individual’s overall life satisfaction and quality. However, the questions on the ALA do assess overall satisfaction with participation (e.g., doing what you want to do) and psychosocial adjustment; thus, it indirectly targets issues of general QoL without directly asking about issues such as mobility or overall health. Moreover, the ALA provides the clinician or researcher with the option to determine if low ratings are related to aphasia or to some other factor (e.g., impaired mobility).

the ALA discriminated between severity groups on the language domain suggests ALA self-rating of language impairment was predictive of clinician severity ratings, thus supporting construct validity. The failure to discriminate between moderate and severe groups on participation, personal factors, and total scores was not unexpected, since degree of severity is not necessarily directly translatable to these elements of QoL (e.g., Ross & Wertz, 2002). For example, people with severe aphasia might perceive their participation as satisfactory, while someone with moderate aphasia might be unsatisfied with their participation. The fact that the ALA discriminated between mild aphasia and moderate/severe aphasia might relate to the fact that members of the mild group were very mildly impaired as reflected in ratings of 5 on the BDAE severity rating (“minimal discernible communication disability”). Perhaps people with very mild aphasia are more likely to successfully reintegrate into former or new lifestyles, while persons with moderate or severe disability are more likely to encounter some barriers to living successfully with aphasia, and this is reflected in their ALA scores. Instrument accessibility It was the subjective impression of the research SLPs that the pictographs and key words did not interfere with participation of individuals with mild aphasia, but did facilitate participation of individuals with moderate and severe aphasia. Future research might specifically address the perceptions and preferences of people with aphasia across a range of severities regarding the pictographic format.

Domain scores This initial evaluation of the ALA focuses on test– re-test reliability and construct validity of questions designed to represent life with aphasia; these questions were organized into a priori ICF domains in order to provide insight into the relative contribution of these conceptual domains to overall life with aphasia as measured on the ALA. Thus, aspects of psychosocial adjustment, participation, environment, and language were assessed from the perspective of the person with aphasia. Organization of the ALA into these ICF domains is in line with trends in rehabilitation in general. Future research is needed to aid in interpretation of the domain scores. In addition, further research is needed to interpret the moving on with life question. Discriminant group analysis Results from discriminant analysis suggest that the ALA discriminates between mild, moderate, and severe aphasia on the language domain and between mild and moderate/severe aphasia for participation, personal factors, and the total score. The fact that

Limitations of the current study Appropriate skill of the SLP in communication support is deemed necessary for valid and reliable administration of the ALA. The research SLPs in this study were not only trained in ALA administration, but also were skilled in communication support. Although communication support is a widely used method of facilitating communication with people with aphasia (Alarcon & Rogers, 2010; Kagan, 1998; Kagan et al., 2001), the level of training of the SLPs in this study constitutes a potential limitation since practicing clinicians might not have similar training. Also, the current project did not address inter-rater reliability; varied levels of skill and the ability to implement the conversational script may affect agreement across raters. Finally, the degree of support offered by the SLP during administration may introduce bias (as compared to independent self-report instruments). This potential limitation is partially mitigated by verification techniques designed to ensure that the viewpoint of the person with aphasia is correctly represented in the scoring. In order to address potential reliability

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issues, a training DVD has been developed to identify key features of administration; this DVD and a manual outlining features of test administration are included with the ALA. Another limitation of this study was the potential occurrence of life altering events between first and second administrations of the ALA. Since this question was not addressed with participants, it is impossible to determine if intervening events affected ALA results on the second administration. However, if this were the case, the bias would likely be towards lower correlations; thus, ICC estimates are conservative. Finally, fully coherent comparison measures for demonstrating construct validity were not available. The scales that we used to measure construct validity included elements similar to the ALA. While this likely impacted the strength of correlations between the ALA and the other measures, the lack of ideal comparison measures demonstrates the need for aphasia-friendly tools that specifically target living with aphasia.

Future directions and conclusions As with any new measure, user experience and input will inform future development of the ALA. However, several research questions remain to be answered. Future research might focus on additional psychometric analysis such as factor analysis or Rasch analysis to further analyse the properties of the ALA. Also, research testing the ALA’s sensitivity to change over time and after intervention is needed. Currently, research is being conducted using the ALA to document longitudinal changes in life with aphasia during the first year poststroke (Worrall, Simmons-Mackie, Kahn & Brown, in progress); such data will contribute to knowledge regarding the sensitivity of the ALA. Research might also focus on the sensitivity of the ALA to changes after particular interventions believed to impact life quality with aphasia. In addition, future research is needed to test inter-rater reliability of the ALA and use of the ALA by SLPs who have access to the ALA DVD training but who have not received the more rigorous training provided for the study SLPs. In conclusion, the ALA is an aphasia friendly measure that allows people with aphasia to participate in reporting aspects of their own QoL. Reliability and validity data suggest that the ALA shows promise for evaluating aphasia-related QoL from the perspective of the person with aphasia.

Note 1.

The published version of the ALA reflects the removal of items based on reliability and validity results.

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