PERSONS WITH MULTIPLE sclerosis (MS) have cognitive

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1 ORIGINAL ARTICLE The Relation Between Subjective and Objective Measures of Everyday Life Activities in Persons With Multiple Sclerosis Yael Goverover, PhD, OT, Jessica Kalmar, PhD, Elizabeth Gaudino-Goering, PhD, Marla Shawaryn, PhD, Nancy B. Moore, MA, June Halper, MSN, ANP, John DeLuca, PhD, ABPP ABSTRACT. Goverover Y, Kalmar J, Gaudino-Goering E, Shawaryn M, Moore NB, Halper J, DeLuca J. The relation between subjective and objective measures of everyday life activities in persons with multiple sclerosis. Arch Phys Med Rehabil 2005;86: Objectives: To investigate the relation between subjective and objective performance-based measures of functional status in persons with multiple sclerosis (MS), and to compare their performance with healthy controls. Design: A between-groups design, using a correlational approach to examine the relation between objective and subjective measures of functional capacity. Setting: Outpatient rehabilitation research institution. Participants: Seventy-four subjects with clinically definite MS and 35 healthy controls. Interventions: Not applicable. Main Outcome Measures: The Executive Function Performance Test (EFPT), Functional Assessment of Multiple Sclerosis (FAMS), and Functional Behavior Profile (FBP). Results: MS participants reported more difficulties performing functional tasks than did the healthy controls. MS participants also performed significantly worse on the EFPT than healthy controls. However, all correlations between subjective and objective functional measures were nonsignificant. After controlling for depressive symptomatology, EFPT performance was significantly associated with FBP scores, but not FAMS scores. Conclusions: The lack of association between objective performance-based measures and subjective self-report measures of functional activities is a challenge to outcomes measurement and has implications for assessment of functional performance. Results are discussed in terms of the different dimensions that these tools are measuring and their respective strengths and limitations. Key Words: Activities of daily living; Multiple sclerosis; Outcome assessment (health care); Rehabilitation by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation From the Kessler Medical Rehabilitation Research and Education Corp, West Orange, NJ (Goverover, Kalmar, Gaudino-Goering, Shawaryn, Moore, DeLuca); University of Medicine and Dentistry of New Jersey New Jersey Medical School, Newark, NJ (Goverover, Kalmar, Shawaryn); and Gimbel Multiple Sclerosis Center, Holy Name Hospital, Teaneck, NJ (Halper). Supported by the National Multiple Sclerosis Society (grant no. RG 2596B2/2) and the Henry H. Kessler Foundation. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to John DeLuca, PhD, ABPP, Neuropsychology and Neuroscience Laboratory, Kessler Medical Rehabilitation Research and Education Corp, 1199 Pleasant Valley Way, West Orange, NJ 07052, jdeluca@kmrrec.org /05/ $30.00/0 doi: /j.apmr PERSONS WITH MULTIPLE sclerosis (MS) have cognitive difficulties that can significantly affect everyday life functional activities, such as the ability to be gainfully employed, 1,2 and experienced more difficulties in activities of daily living (ADLs), such as simple homemaking activities, relative to persons with MS who were cognitively intact. 2-4 However, most of the assessment tools used to assess functional status were based on self-reports that were heavily weighted toward physical impairments. Additionally, subjective reports do not always mirror objective-based measures of functional status. 5-7 Important information concerning the functional level of persons with MS may be provided through performance of instrumental ADLs (IADLs). 8,9 IADLs are considered to be of a higher order than basic ADLs and usually require physical and cognitive capacities, both of which can be affected in persons with MS. IADL status can be assessed either objectively or subjectively. Objective observation or direct assessment of performance provides an accurate index of a person s functional status. 10 However, direct performance-based assessments cannot always be conducted because of safety issues, time and/or space restrictions, or a patient s physical and/or medical condition. Because of these limitations, clinicians and researchers often rely on subjective reports of IADL performance, made either by the individual (self-report) or by a family member or an informant (proxy reports). Self-report assessments, however, have been criticized for 2 major reasons. First, people often have difficulty evaluating their everyday competency accurately (see, for example, Rubenstein et al 6 ). Second, self-report assessment of everyday competency is of limited usefulness because it provides little or no information about the real or perceived causes of a person s incapacity to perform specific tasks of daily living. 7 Because of the limitations of indirect, subjective assessment procedures and the increased acceptance of direct assessments of actual IADL performance, the focus of IADL research in recent years has been on the development of tests of everyday task performance with documented psychometric properties that can be administered in restricted settings. Most studies of subjects who have MS have focused on the relation between measures of functional ability and measures of global cognitive status. 1,2,4 Although these examinations provide information on the impact of cognitive deficits on functional ability, such studies typically make use of clinical measures of functional status that may not be sensitive to very mild cognitive impairments in everyday activities. 11 Other studies have attempted to elucidate the relation of health status to impairments in IADLs using traditional self-report measures of competence 3,12 or functional composite, 13,14 such as the Expanded Disability Status Scale (EDSS) 15 and the Multiple Sclerosis Functional Composite (MSFC). 16 However, it is difficult to categorize the EDSS and the MSFC as objective measures of functional status because these instruments measure impairment, not disability or handicap. 17 Recently, interest in how objective or performance-based measures of func-

2 2304 RELATION BETWEEN MEASURES OF IADLS, Goverover tioning compare with subjective reports (self- or proxy reports) of functional performance has emerged, 10,18 showing only moderate to weak relationships To our knowledge, in the only such study of subjects with MS, Doble et al 21 examined the relation between Assessment of Motor and Process Skills (AMPS) 22 scores and standard clinical ratings on the EDSS as well as the relation between AMPS scores and subjective ratings of general health status with the Sickness Impact Profile. 23 These authors found that participants with MS who would not have been expected to have IADL difficulties on the basis of ratings of neurologic impairments were actually impaired in their IADL performance (as measured by the AMPS). Correlations were significant between the ratings of subjective measures and the motor components of the AMPS, but not the process skills components. Previous research suggests that variables such as affect symptomatology may reduce the relation between self-reports and performance-based assessments. 24 For instance, depressive symptomatology is more strongly associated with subjective self-report functioning than with performance-based functioning 18,20 and persons with depressive symptomatology tend to underestimate their level of function, 18,20 even in those with MS. 25,26 The current study examined the relation between objective performance-based measures of IADLs and patient and proxy reports of IADL functioning and the effect of depressive symptomatology on these relations. The present study examined 2 main questions: (1) Would performance of the Executive Function Performance Test (EFPT) correlate with self-report and proxy reports of functional performance in persons with MS and healthy controls? (2) Would the relation between selfreport of functional performance and functional performance of the EFPT change after controlling for depression? METHODS Participants Participants consisted of 74 subjects with clinically definite MS 27 and 35 healthy control participants without any reported neurologic disabilities. The 2 groups were matched in age, sex, and years of education (table 1). All participants were between the ages of 21 and 64, were free of any history of neurologic illness or injury (aside from MS), alcohol or drug abuse, and Table 1: Characteristics of the MS and Healthy Control Samples Characteristics MS Controls F P Age (y) Education (y) BDI score EDSS score Ambulation Index score Sex (%) 2 1 test Male Female Disease type (%) RR 66.2 NA Primary progressive 10.8 NA Secondary 17.6 NA progressive Other 5.5 NA NOTE. Values are mean standard deviation (SD) or as indicated. Abbreviations: BDI, Beck Depression Inventory; NA, not applicable; RR, relapsing remitting. psychiatric illness. All MS participants were at least 1 month postexacerbation and were free of corticosteroid use. Participants had to have sufficient visual acuity to see the test materials. Thus, participants whose vision was significantly impaired by scotomas (corrected vision in worse eye 20/60), diplopia, or nystagmus were excluded. As a screen for dementia, participants also had to score above 18 on the Cognitive Capacity Screening Examination. 28 Most MS participants (66.2%, n 49) had a relapsing remitting course, 17.6% (n 13) had secondary progressive MS, 10.8% (n 8) had primary progressive type of MS, and in 5.5% (n 4) disease course was unclear. Overall, the MS sample was experiencing mild physical impairment, with a mean ambulation index standard deviation (SD) of Depressive symptomatology was significantly elevated in the MS group versus the control group based on the Beck Depression Inventory (BDI) (F 1, , P.001). The average score of the MS group on the BDI is indicative of a mild level of depressive symptoms, although, given the heavy emphasis on somatic and vegetative signs on the BDI, which may be due to actual MS symptoms, this level of depressive symptomatology is likely an overestimate. 29 Research Instruments Functional status tasks objective measure: EFPT. The EFPT 30 is a standardized, performance-based assessment that examines cognitive functioning through the observation of cues needed for a person to carry out a functional task. The cueing system is a series of visual, gestural, and physical aids that are given in a hierarchical fashion. These cues provide support to the subject when task execution begins to fail. The type of cueing required (visual, gestural, physical) is an indication of the nature and degree of the impairment causing the failure. These cues are only recorded in response to cognitive failures during the task. If a subject cannot execute a step because of a physical limitation (eg, lifting a pot of water), this is not scored as a failure. The EFPT examines the execution of 6 ADLs: hand washing, simple cooking (cook oatmeal), telephone use, medication management, and bill payment. In the present protocol, an additional task (a complex cooking task) was added to the EFPT protocol. In this task, participants were required to make a casserole. The level of cueing given during the performance of each of the 6 tasks served as the dependent variable for the EFPT. Each task was rated using 5 task procedures: initiation, organization, sequencing, task completion, and judgment, and safety. For each of the 5 task procedures, behavioral performance was scored using a scale from 0 to 5 as follows: no cues required (0 points), verbal guidance (1 point), gestural guidance (2 points), direct verbal assistance (3 points), physical assistance (4 points), do for subject (5 points). Task administration was standardized to ensure reliability of measurement. For each task, the 5 procedure scores were totaled, creating a summary score for each of the 6 ADLs. The 6 independent task scores were then summed to represent a total EFPT score. Range of the EFPT scores can be between 0 (participants performed the task independently and did not require any cue to perform the task) to 150 (not independent and require physical assistance to complete all of the tasks). Functional status tasks subjective measures: Functional Assessment of Multiple Sclerosis. The Functional Assessment of Multiple Sclerosis (FAMS) 31 is a self-report instrument used to assess quality of life (QOL) in people with MS. The scale consists of 59 items divided into 6 subscales: mobility, symptoms, emotional well-being, general contentment, thinking/fatigue, and family/social well-being. For each item, participants rate their symptoms on a 5-point Likert-type scale,

3 RELATION BETWEEN MEASURES OF IADLS, Goverover 2305 with higher scores indicating independence and lower scores indicating greater difficulty in everyday performance and lower QOL. According to Cella et al, 31 only items 1 through 44 on the FAMS are included in the total score; items 44 through 59 are not included. Thus, scores can range from 0 (have many troubles related to QOL) to 176 (do not report to having any troubles related to QOL). Functional status tasks subjective measures: Functional Behavior Profile. The Functional Behavior Profile (FBP) 32 is a 27-item questionnaire filled out by both participants and an informant. It was designed to measure the overall capacity of the impaired person to engage in tasks, social interactions, and problem solving. The self-report and proxy report (ie, caregiver or significant other) versions of the scale use the same questions. All of the questions relate to how the person with impaired cognitive function performs in his/her daily activities during the past week. Evidence for construct validity has been provided with correlations of.70 to.96 with other proxy reports of functional status in people ranging from questionable to severe dementia, including the Clinical Dementia Rating Scale (completed by a clinician) and the Blessed Dementia Rating Scale (completed by a caretaker or significant other). Participants rate their symptoms on a 5-point Likert-type scale and scores range from 0 (have many troubles related to functional behavior) to 108 (no troubles related to functional behavior). Emotional function: depression. The BDI 33 is a wellestablished 21-item self-report assessment of the presence and severity of depressive symptoms. Procedure Participants were recruited by advertisements distributed at local support groups and clinics. On initial telephone contact, potential participants were screened based on the inclusion and exclusion criteria discussed above. Participants who met the inclusion criteria were then scheduled for an interview and testing. Before study enrollment, all participants indicated willingness to participate in the study by signing a consent form approved by an institutional review board. Testing was performed on 2 separate occasions. At 1 session, which lasted approximately 4 hours, an extensive battery of neuropsychologic tests was administered. The other session lasted for approximately 2 hours, during which participants were administered self-report questionnaires in regard to their functional independence and an IADL functional assessment (the EFPT) in pseudorandom order. Data Analysis Data were analyzed in 3 stages. First, descriptive and comparison analyses were performed on the study instruments, which included EFPT performance, scores obtained on the FAMS questionnaire, and the self and proxy versions of the FBP questionnaire. Scores obtained by participants with MS were compared with those of the healthy controls using 1-way analyses of variance (ANOVAs). Second, Spearman rank correlations were performed between the EFPT scores and the scores obtained on the FAMS and the FBP for the subjects with MS and the healthy controls. This analysis allowed for the examination of the relation between an objective measure of functional performance (EFPT scores) and subjective measures of functional performance (FAMS and FBP scores). Third, multiple regression analyses were performed to evaluate the relation between objective performance of everyday functioning and perceived functional performance (by participants with MS) while controlling for depressive symptomatology, as indicated by BDI scores. Proxy reports were not used for these regression analyses because of their high correlation with selfreport. Furthermore, depressive symptomatology is more associated with self-perception, as opposed to proxy report, of functional capacity. 26,34 RESULTS Group Comparisons on Measures of Everyday Functional Performance One-way ANOVAs were conducted to compare EFPT total scores and EFPT subtest scores across groups. EFPT scores for the 2 groups are presented in table 2. The EFPT total score was significantly higher in the MS group than in the control group, indicative of a higher level of cueing required to complete the EFPT tasks (F 1,82 4.4, P.038). Of the 6 EFPT tasks, subjects with MS performed significantly worse than healthy controls on both the bill paying (F 1,98 6.6, P.01) and medication tasks (F 1, , P.047). There were no other statistically significant differences observed between the 2 groups in the individual subscales of the EFPT. One-way ANOVAs were also conducted to compare selfreport of functional performance for the healthy control and MS groups on the FAMS and FBP, as presented in table 3. Participants with MS reported significantly more problems (mean, ) in functional performance than healthy controls (mean, ) on the FAMS questionnaire (F 1, , P.001). The same pattern of results was observed on the FBP self-report, where participants in the MS group reported more trouble in everyday functioning than healthy participants (F 1, , P.001). In addition, proxy report of functional behavior indicated by ratings of the FBP was also significantly different between the 2 participant groups (F 1, , P.001), with informants reporting more functional performance difficulties in subjects with MS than in healthy participants. Correlational Analysis of Measures of Everyday Functional Performance To examine the relation between EFPT scores and selfreport ratings of functional everyday performance, Spearman rank correlations were calculated between EFPT total scores and its subtests and the self-report ratings (ie, FAMS, FBP self-report, FBP significant other ratings) for the MS group. These correlations are presented in table 4. Statistically significant correlations were found among all the self-report measures (ie, FBP, FAMS). However, no significant correlations were found between scores obtained in the EFPT and any of the self-report measures. Significant correlations were found between the total score of the EFPT and 5 of Table 2: EFPT Scores: Comparison Between Groups Measures MS (n range, 59 69) HC (n range, 24 31) F P EFPT total Hand washing Simple cooking Using the phone Complex cooking Taking medication Paying bill NOTE. Values are mean SD. Abbreviation: HC, healthy controls.

4 2306 RELATION BETWEEN MEASURES OF IADLS, Goverover Table 3: Subjective Measures Scores: Comparison Between Groups Measures MS (n range, 55 70) HC (n range, 27 35) F P FAMS FBP self FBP proxy (family) NOTE. Values are mean SD. its subtests scores. Only the hand-washing task was not significantly correlated with the total EFPT score. Similar analysis (Spearman rank correlations) for the healthy control participants showed the same pattern of results. No significant correlations were found between scores obtained in the EFPT and any of the self-report measures. Depressive Symptoms and Measures of Everyday Functional Performance FAMS self-report measure and rates of depressive symptomatology were examined in relation to performance on the EFPT. Multiple linear regression analysis was performed with EFPT total scores as the dependent variable, and FAMS and BDI scores as independent variables. In this model, it was found that neither depressive symptoms nor the FAMS explained a significant portion of the variance of the EFPT. This model (see model 1, table 5) accounted only for 1% of the variance in EFPT scores and it was not significant (F 2,50.253, P.77). Thus, FAMS self-report and depressive symptomatology did not predict and explain any of the variance in the total EFPT performance scores. A second multiple regression analysis was conducted with the EFPT total score as the dependent variable, with depressive symptoms and FBP patient self-report score as independent variables (see model 2, table 5). The proportion of EFPT variance explained by depressive symptoms and FBP score was 8.6% and it was not significant (F 2,50 2.2, P.117). Level of depressive symptomatology did not make a significant contribution to this model. However, the FBP self-report score made a significant contribution to this model (.14, t 1.9, P.055). Thus, FBP self-report predicted a small portion of the EFPT variance when depressive symptomatology was controlled for. DISCUSSION The present study examined the relation between 3 subjective measures (FAMS, FBP proxy, FBP self-report) and 1 Table 4: Correlations Between Objective and Subjective Measures of Functional Performance for Subjects With MS (n range, 50 69) Measures EFPT Total Score FBP Self FBP Proxy FAMS Hand washing Simple cooking Using the phone Complex cooking Taking medication Paying bill FAMS * FBP proxy (family) FBP self.07 *P.05. P.01. Table 5: Summary of Multiple Regression Analysis Predicting Objective Performance-Based Measure Using Subjective Self- Report Measures and Depressive Symptomatology Model R 2 P Model 1 EFPT BDI FAMS Model 2 EFPT BDI FBP self-report objective, performance-based assessment tool (the EFPT) of everyday life functional status, and compared performance on these tools between subjects diagnosed with MS and healthy controls. Persons with MS reported (FBP, FAMS) subjectively experiencing significantly more problems in community activities than the healthy participants. Also, on objective measure of actual performance, the EFPT, the MS group performed significantly worse than healthy subjects. However, all correlations between subjective and objective functional performance measures were low and nonsignificant. This lack of relation between objective and subjective assessments of everyday life activities is consistent with existing studies in both MS 13,21 and other populations. 10,20 The findings of the current study suggest that there is little to no relation between the objective performance-based and the subjective self-report assessment tools used in this study. The lack of a significant relation suggests that the objective-performance-based measure and the subjective self-report measures each provide unique contributions to the evaluation of functional performance in persons with MS. Self- or proxy report can provide information about patient or caregiver perceptions regarding the level of participation in activities that cannot be measured using an objective performance-based assessment tool. Objective IADL measures are usually task oriented and are rated along a number of dimensions that can be physical and/or cognitive. This type of observation and measure enables the observer to make a judgment as to the particular aspect of an activity that can or cannot be performed independently. 8 As such, reliance solely on self-report assessments of everyday activities may provide information that may not reflect actual performance in everyday life. There are several potential reasons for the inconsistencies between self-report and performance-based measures of IADL. First, self-report and performance-based measures of IADL have often been developed with different conceptual bases in mind. For example, self-report measures may contain items related to aspects of QOL whereas performance-based measure may contain items that are related only to the cognitive and motor aspects of actual performance. 13,17 The second potential explanation for the lack of consistency between self-report and actual performance of IADLs is related to characteristics of the person being evaluated. Previous research suggest that sex, 10 cognitive functioning, 20 and affective functioning 34 may reduce the concordance between self-report and performance-based measures of functional status. 18 Overall, the choice of self-report versus performancebased assessment is in large part determined by the nature of the assessment question. Self-report instruments may provide useful information about the client s view and perspective, such as issues related to cultural background, motiva-

5 RELATION BETWEEN MEASURES OF IADLS, Goverover 2307 tion, perceptions, and life choices. Performance-based tools are best used when behavioral samples of everyday-life activities (how one responds to cues or to the environment) are needed as part of the assessment. The results of the present study suggest that one method should not be used as a substitute for the other. Despite significant elevations relative to controls, the mean BDI score for the MS group reflected only mild depressive symptoms, several of which likely result from actual MS symptoms (physical, cognitive) rather than depression per se. 29 Current results showed that BDI scores did not significantly predict performance on the EFPT assessments. However, after controlling for symptoms of depression, scores on the FBP (but not the FAMS) were significantly associated with EFPT performance. Thus, the current results support and extend previous findings that depressive symptomatology may distort patients perception of their IADLs and QOL (see Benedict, 24,26 Heinze, 25 Maor 34 and colleagues). This suggests that functional complaints about ADLs could actually represent emotional distress rather than reflections of actual life performance. Relying solely on client s self-report of overall functional performance may misrepresent actual functional performance and may lead to intervention plans that are less than optimal. 34 CONCLUSIONS When interpreting the results of the present study, it is important to consider several factors that may limit its generalizability, most notably, the choice of assessment tools used. The EFPT was originally designed to assess cognitive functioning during performance of IADL tasks primarily for persons with dementia. 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