Acta Neurol Scand 2015: 132: 226–234 DOI: 10.1111/ane.12387

© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd ACTA NEUROLOGICA SCANDINAVICA

Development and validation of the multiple sclerosis questionnaire for the evaluation of job difficulties (MSQ-Job) Raggi A, Giovannetti AM, Schiavolin S, Confalonieri P, Brambilla L, Brenna G, Cortese F, Covelli V, Frangiamore R, Moscatelli M, Ponzio M, Torri Clerici V, Zaratin P, Mantegazza R, Leonardi M. Development and Validation of the Multiple Sclerosis Questionnaire for the Evaluation of Job Difficulties (MSQ-Job). Acta Neurol Scand 2015: 132: 226–234. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. Objective – Multiple sclerosis (MS) affects young adults of working age. Difficulties in work-related activities are usually ascribed to MS symptoms, while the impact of workplace features is underestimated. This article presents the Multiple Sclerosis Questionnaire for Job Difficulties (MSQ-Job), designed to assess working difficulties due to MS symptoms and workplace features. Methods – A sample of employed MS patients completed the MSQ-Job, the WHO-Disability Assessment Schedule (WHODAS 2.0) and the 54-items MS Quality of Life Questionnaires (MSQOL-54); the expanded disability status scale (EDSS) was used to define MS severity. Factor structure was evaluated using principal component extraction and Oblimin rotation; internal consistency was assessed with Cronbach’s alpha; construct and discriminant validity using t-test (EDSS 0-2 vs >2; patients selfreporting need for support vs patients reporting no needs; full-time vs part-time employees); and Pearson’s correlation with WHODAS 2.0 and MSQOL-54. Results – The MSQ-Job is a 42-item questionnaire with six scales and an overall factor. Scores range on a 0–100 scale (higher scores indicate more and more severe difficulties); patients with EDSS>2 and self-reporting support needs had worse scores than those with EDSS 0-2 and without needs. Correlations with WHODAS 2.0 and MSQOL-54 were generally significant (P < 0.0007) and below 0.70. Conclusions – The MSQ-Job jointly measures the impact of respondents’ symptoms and workplace features on work activities and enables to assess the effects of clinical and occupational interventions and better describe the impact of MS indirect costs.

Introduction

Multiple sclerosis (MS) is a neurological disease with a progressive course that mainly affects women aged 20–40 (1): in Europe, its incidence is 4.3/100.000 inhabitants/year and the prevalence is 54-232/100.000 (2, 3). The most prominent social consequence of MS is reduced employability: the unemployment rate of MS patients of working age is around 60% (4, 5), and, among those employed, 23.4% had to reduce the amount of worked hours and 25.8% had to change the type 226

A. Raggi1, A. M. Giovannetti1, S. Schiavolin1, P. Confalonieri2, L. Brambilla2, G. Brenna3, F. Cortese 3, V. Covelli1, R. Frangiamore2, M. Moscatelli2, M. Ponzio4, V. Torri Clerici2, P. Zaratin4, R. Mantegazza2, M. Leonardi1 1 Department of Neurology, Public Health and Disability Unit, Neurological Institute C. Besta IRCCS Foundation, Milan, Italy; 2Department of Neuroimmunology, Neurological Institute C. Besta IRCCS Foundation, Milan, Italy; 3Scientific Directorate, Neurological Institute C. Besta IRCCS Foundation, Milan, Italy; 4 Scientific Research Area, Italian Foundation of Multiple Sclerosis, Genoa, Italy

Key words: multiple sclerosis; employment; work difficulties; disability evaluation; validation studies; factor analysis A. Raggi, Neurology, Public Health and Disability Unit, Neurological Institute C. Besta IRCCS Foundation, Via Celoria 11, 20133 Milano, Italy Tel.: +39.02.2394.3105 (2521) Fax: +39.02.2394.2442 e-mail: [email protected] Accepted for publication 26 January 2015

of work (4). The treatment of MS is complex and includes medications that vary consistently with symptoms and disease stages, for example immunomodulating and immunosuppressive treatments, corticosteroids, physical and occupational therapy (6), and vocational rehabilitation (7). In consideration of MS prevalence, young age of onset and unemployment rates, it is not surprising that its cost is one of the highest among brain disorders (approximately 27000€ per patient/year) and that one-third of the overall cost is indirect (3).

Validation of the MSQ-Job As reported in a recent review, data on patients’ difficulties in work-related activities are mostly ascribed to fatigue, mobility and cognitive impairments; on the contrary, the role of working environment is underestimated or neglected (5). Studies mostly address whether a person with MS is employed or not, and patients’ perception of MS characteristics and the impact of neuropsychological symptoms on working activities are largely unexplored (8–11). Some studies focused on health-related quality of life (HRQoL) as an outcome, showing that being employed is related to better HRQoL (12–14). Systematic evaluations of environmental factors involved in patients’ ability to work are lacking as well, and few issues were associated with the risk of unemployment in MS patients. These include suitable work tasks (e.g. tasks not requiring physical effort could help patients experiencing fatigue to maintain their job); lack of flexibility that makes it difficult balancing work duties with the need to follow therapies and schedule visits (15); and the employers’ failure to provide support and reasonable accommodation (16, 17). Vocational interventions might provide support to the patient to manage several aspects of MS in the workplace, including disclosure and workplace accommodations, and might offer emotional support, enhance work performance and provide education to employers on MS (7, 18). To our knowledge, there are two instruments focused on work issue in MS patients. The first is the Multiple Sclerosis Work Difficulties Questionnaire (MSWDQ) (19) that measures 12 dimensions connected to subjective workplace difficulties: general cognitive difficulties, prospective memory difficulties, fatigue, movement/ mobility difficulties, workplace inaccessibility, pain/temperature difficulties, bladder/bowel difficulties, low self-esteem, interpersonal difficulties, non-supportive workplace, work/home balance difficulties and financial security concerns. The second questionnaire is the MS-specific Work Instability Scale (MS-WIS) that addresses work instability, that is unbalance between MS aspects and the organizational, social and psychological aspects of working environment that might determine risk of job loss (20). The MSWDQ poorly addresses the effects of a hindering environment, that is the extent to which a worker with MS experiences difficulties due to negative attitudes of the workplace in terms of organization, role and responsibilities. Such aspects are better captured by the MS-WIS that, however, does not measure the specific problems a person with MS might experience in the workplace. Therefore, in

our opinion, no instrument is available to address difficulties in work-related activities in patients with MS and integrate the impact of the disease, that of environmental factors and their interaction. In consideration of the high variability of MS symptoms, work tasks and features of working environment, a wide perspective and a biopsychosocial approach are therefore needed to cover all these aspects (21). The aim of this paper was therefore to present the development and validation of the Multiple Sclerosis Questionnaire for Job Difficulties (MSQ-Job), a questionnaire intended to evaluate difficulties in work-related activities as a function of both MS symptoms and working environment features. Materials and methods Item generation

Items were developed based on the results of a literature review we had previously carried out to assess available knowledge on MS-specific jobrelated problems (5). In brief, a total of 26 papers published between 2002 and 2011 that reported difficulties at work, predictors or correlates of these difficulties were selected. The most common themes were job difficulties, factors related to quality of life, unemployment, job loosing and job finding, and other work-related issues such as relationships with colleagues and supervisors. These data were merged with those identified by the Italian MS society in its White Book on disability in MS (22). One author prepared a comprehensive list of the core issues contained in the two documents. These included factors related to quality of life, which is known to be associated with unemployment (17 themes); factors related to unemployment in MS patients (five themes); and factors connected with entering and exiting the workforce (30 themes). Such themes were expanded based on these data, and a list of 105 items was prepared. A consensus approach was used to select items for the preliminary version of MSQ-Job. The group of researchers, composed of neurologists, psychologist and members of the Italian MS society, revised the comprehensive list establishing priorities for each single item. After redundant items were eliminated, a total of 70 items were defined, roughly divided in three macro areas: difficulties due to clinical symptoms (28 items), to personal features (16 items) and to environmental/contextual factors (26 items). Items had to be rated taking into account how much of an impact 227

Raggi et al. the difficulty or problem identified by the item might have on work difficulties: 1 – no impact; 2 – mild; 3 – moderate; 4 – severe; or 5 – complete impact. A brief pilot study on 19 patients was carried out prior to data collection to ensure that items did not contain technical jargon and were comprehensible to patients. Patients and setting

The validation study was carried out between January and September 2013 at the Neurological Institute C. Besta. We enrolled patients aged 18– 65, with a diagnosis of relapsing–remitting MS (RRMS), secondary or primary progressive MS according to McDonald’s criteria (23), who voluntarily accepted to participate in the study on the occasion of hospital admission or outpatient visit. All patients had to be in the workforce, including those on sick leave. We also included those who had left their job 0.25. Suitability of data for factor analysis was assessed with Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy (KMO adequate if >0.50) (27) and Bartlett’s test of sphericity (BTS; adequate if P < 0.05) (28). Eigenvalue ≥1 was used as a criterion for component extraction. Items that loaded in a same way on more than one factor and that had loadings 0.70 (30), if item-total correlation indexes were >0.40 and average interitem correlations were comprised between 0.30 and 0.70 (31).

Validation of the MSQ-Job Construct validity – Construct validity was tested by assessing differences in MSQ-Job scales across patients with different severity profiles, between patients self-reporting support need or no support needs in daily work and non-work activities, and between patients with full-time or part-time employment status. MS severity was measured with the EDSS: due to the low average EDSS typically observed in employed MS patients, we compared two groups: those with low disabling MS (EDSS 0-2) and those with moderately to severely disabling MS (EDSS >2). Two were the reasons to set the threshold at EDSS = 2: first, as our sample was composed only of patients currently employed, we deem that setting a threshold to a higher EDSS level would make the two groups’ sample sizes largely unequal; second, previous literature findings indicate that in a sample of early-stage RRMS patients, mean EDSS was 1.9 among employed and 2.6 among unemployed patients (13). It is expected that patients with higher EDSS, those self-reporting needs for support in daily work and non-work activities and those with a full-time employment status will have worse MSQ-Job scores: independent-sample t-test was used to assess this difference. Statistical significance was at one-tailed P-value 2 (n = 60)

8.0  14.4

16.6  19.0

11.0  13.5

15.1  16.6

11.2  13.4

26.6  22.7

6.2  12.1

10.7  16.6

7.5  16.1

9.2  17.4

12.4  19.9

11.5  16.7

9.7  10.9

15.0  13.7

Support need

t-test 3.08* P = 0.001 1.64 P = 0.052 4.82* P < 0.001 1.87 P = 0.032 0.66 P = 0.256 0.29 P = 0.387 2.61 P = 0.005

Yes (n = 20)

No (n = 161)

27.5  21.5

8.7  14.6

26.2  19.5

10.6  13.0

35.5  17.5

13.9  17.2

16.7  19.3

6.6  12.6

13.9  21.7

7.3  15.7

18.0  22.3

11.3  18.3

23.2  14.6

10.0  11.0

Employment Status

t-test 3.80* P < 0.001 3.48* P < 0.001 5.23* P < 0.001 3.16* P < 0.001 1.32 P = 0.100 1.50 P = 0.067 3.92* P < 0.001

FT (N = 35)

PT (N = 140)

12.7  18.8

10.4  16.0

17.0  15.1

11.4  14.5

19.6  18.0

15.5  18.5

10.6  17.2

6.0  12.8

11.2  20.6

7.4  15.5

19.8  25.7

10.4  16.6

15.4  13.2

10.6  11.8

t-test 0.75 P = 0.227 2.02 P = 0.022 1.18 P = 0.119 1.41 P = 0.079 1.22 P = 0.113 2.66 P = 0.004 2.12 P = 0.018

*t-test is significant at P < 0.0023 after Bonferroni correction (21 multiple comparisons).

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Raggi et al. Table 4 Pearson’s correlations between MSQ-Job, WHODAS 2.0 and MSQOL-54 Tactile perception and fine movement WHODAS-2 UC GetAr SC GetP HA WA PS SDS MSQOL-54 PCS MCS

Fatigue-related mental functions and symptoms

Movement and fatiguerelated body functions

Psychological and relational aspects

Time and organization flexibility in the workplace

Company’s attitudes and policies

MSQ-Job Total Score

0.392 0.556 0.574 0.559 0.433 0.577 0.630 0.672

0.634 0.397 0.401 0.584 0.427 0.635 0.583 0.673

0.426 0.735 0.513 0.516 0.609 0.637 0.734 0.781

0.409 0.277 0.285 0.493 0.382 0.511 0.453 0.513

– – – – 0.365 0.459 0.323 0.344

0.282 – – 0.291 0.364 0.338 0.338 0.369

0.520 0.542 0.443 0.600 0.588 0.714 0.697 0.761

0.596 0.353

0.579 0.523

0.714 0.424

0.453 0.524

0.367 0.294

0.369 0.310

0.700 0.543

UC, understanding and communicating; GetAr, getting around; SC, self-care; GetP, getting along with people; HA, household activities; WA, work activities; PS, participation in society; SDS, summary disability score; PCS, physical composite score; MCS, mental composite score; – not significant. Significance is set at P < 0.0007 after Bonferroni correction (70 multiple correlations).

The metric properties of MSQ-Job scales are generally satisfactory: internal consistency was always good and the measures of model fit were acceptable, with the exception of ‘company’s attitudes and policies’ subscale. The fact that approximately one-fourth of the patients in our sample were themselves owners of a company or were self-employed (i.e. professionals working in a private practice regimen) may be the reason for this. These patients had a different perspective in addressing negative attitudes or praxes of the company, as qualitatively confirmed by a portion of them, to whom items like ‘lack of good relationships with the employer or lack of comprehension and appreciation’ (item 6.5) made little sense. Correlations with WHODAS 2.0 and MSQOL54 indicate that the constructs underlying the questionnaires are not transposable. Correlations are slightly higher with WHODAS 2.0 summary scores than with MSQOL-54 PCS and MCS. It should be noted that the construct behind MSQJob (i.e. the extent to which a person with MS experiences difficulties in work activities due to MS-related symptoms and job place features) resembles much more that of WHODAS 2.0 (i.e. difficulties in performing a given set of activities due to a health condition) than that of MSQOL54 (i.e. HRQoL): therefore, such a result is not so surprising. Similarly, it is not surprising that ‘work activities’ subscale of WHODAS 2.0 was more strongly correlated with MSQ-Job than the other WHODAS 2.0 subscales. The results of t-test provide some indication on the sensitivity of MSQ-Job in capturing differences due to MS severity. We divided patients on EDSS = 2 threshold to limit the risk of strong sample size inequalities, and because patients with 232

higher EDSS scores are more likely to be unemployed (13, 14): as reported in previous studies, the employment rate of MS patients with EDSS>2 ranged between 33% (32) and 66% (33). Consistently with our hypothesis, patients with higher EDSS reported worse scores at MSQ-Job, but the difference was significant only for ‘tactile perception and fine movement’ and for ‘movement and fatigue-related body functions’ subscales. These scales include symptoms (e.g. physical impairments affecting hands/arms or legs/feet, balance or dizziness, being easily tired) and some difficulties related to these symptoms (e.g. standing for a long period, moving around, walking) that are clearly associated with higher EDSS. Results of t-test were stronger when patients were divided between those self-reporting and those not reporting needs for assistance in daily work and non-work activities: significant difference was herein found also at ‘fatigue-related mental functions and symptoms’ and ‘psychological and relational aspects’ subscales and at MSQJob summary score. It is reasonable that patients that report need for support in daily activities and that also have higher EDSS and longer MS duration might experience difficulties also connected to relational issues and to psychological as well as cognitive ones. Such a result is in line with the results of Ruet and colleagues, that is that cognitive impairments in MS patients at the initial stage of disease increased the risk of quitting their employment (34). The evaluation of these aspects in the MSQ-Job questionnaire is clearly different compared to neuropsychological testing: however, in a non-MS specialty setting, like that of the periodical workplace medical examinations or of occupational and insurance

Validation of the MSQ-Job settings, these items might open the possibility of an accurate evaluation of cognitive functions. We instead found no significant differences, although the trend was consistent with that expected, between patients with full-time or parttime employment status. It is possible to presume that this result is influenced by the differences in sample size, and by the presence of several persons who are self-employed: on one side, these persons have higher control on the amount of worked hours, but at the same time, they are much more involved, in terms of time and commitment, in their work activities. Future studies, with a longitudinal design, should be planned to assess whether shifting from full to part time has a positive effect on the reduction of work-related problems. The last subscales of MSQ-Job, namely ‘time and organization flexibility in the workplace’ and ‘company’s attitudes and policies’ deserve a separate comment. These two scales had the lowest correlations with all MSQOL-54 and WHODAS 2.0 scales, and we found no difference, neither between patients with different EDSS nor between those declaring and not declaring support needs. In our opinion, this is a proof of their novelty: that the content of these two scales is, first, widely underrepresented and therefore innovative and, second, much more dependent on workplace features, rather than respondents’ features, thus opening the possibility to measure the effects of occupational interventions. What the MSQ-Job adds, in terms of content coverage, to existing questionnaires such as MSWDQ and MS-WIS (19, 20) is the possibility to evaluate the impact on work activities of the characteristics of both respondents and workplace with the same questionnaire. Because it provides indications on the impact of MS on work activities, it can be fruitfully used in research settings to connect the amount and severity of working difficulties to indirect costs of MS. Moreover, it could also be used in occupational and insurance settings, to address the utility of a change in one or more working tasks when a patient has major difficulties in fulfilling work requirements and to longitudinally assess the outcome of such nonmedical intervention. Three are the most relevant limitations to this study. First, the sample is quite homogeneous and representative only of early-stage RRMS patients: we therefore do not exactly know the extent to which MSQ-Job is able to describe patients’ difficulties at a higher level of disease progression and severity, that is in those patients that are supposed to have more and more severe job-related problems, which are connected to

increased direct and indirect disease costs. It has, however, to be noted that this sample is likely to be representative of patients still able to carry out work activities, that is patients with RRMS, low EDSS and short disease duration. Therefore, our study is unique in introducing a questionnaire that was able to capture work problems in patients with mild or initial difficulties due to MS. Second, the rate of companies’ owners and self-employed is considerably high: whether this was a random effect of selection or a specific feature of the population of employed MS patients is unknown. Third, the cross-sectional design did not allow to evaluate short- and long-term retest of our questionnaires. Conclusions

We present the development and validation of MSQ-Job, a 42-item questionnaire designed to assess the amount and severity of difficulties in work-related activities in MS patients. The most innovative aspect of MSQ-Job lies in the possibility to measure impact of the characteristics of both respondents and workplace on work activities in a single questionnaire. This enables to assess the different impact of both clinical interventions, that is medications or rehabilitation, and occupational ones carried out in the workplace, such as change in work tasks or reduction of worked hours. In future studies, MSQ-Job could be used to connect the amount and severity of working difficulties to MS indirect costs. Acknowledgment This study was supported by a grant from the Italian National Institute for Insurance against Job Accidents (Istituto Nazionale per l’Assicurazione contro gli Infortuni sul Lavoro – INAIL). The authors wish to thank Anna Moiana for her valuable support in revising the use of English language.

Conflict of interest statement PC is a board member for Biogen-idec and received support for conference travel from Sanofi-Aventis, Biogen Dompe AG and Merck-Serono. RM has served on a scientific advisory board for GlaxoSmithKline, Alexion and Bio-Marin and has received funding for travel and speaker honoraria from Sanofi-Aventis, Merck-Serono and MEDA Pharmaceuticals Inc.

Supporting Information Additional Supporting Information may be found in the online version of this article. Table S1. Full Factor Table.

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Development and validation of the multiple sclerosis questionnaire for the evaluation of job difficulties (MSQ-Job).

Multiple sclerosis (MS) affects young adults of working age. Difficulties in work-related activities are usually ascribed to MS symptoms, while the im...
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