The online version of this article (doi:10.1186/s12883-017-0834-1) contains supplementary material, which is available to authorized users.
The Multiple Sclerosis Questionnaire for Physical Therapists (MSQPT) is a patient-rated outcome questionnaire for evaluating the rehabilitation of persons with multiple sclerosis (MS). Responsiveness was evaluated, and minimal important difference (MID) estimates were calculated to provide thresholds for clinical change for four items, three sections and the total score of the MSQPT.
This multicentre study used a combined distribution- and anchor-based approach with multiple anchors and multiple rating of change questions. Responsiveness was evaluated using effect size, standardized response mean (SRM), modified SRM and relative efficiency. For distribution-based MID estimates, 0.2 and 0.33 standard deviations (SD), standard error of measurement (SEM) and minimal detectable change were used. Triangulation of anchor- and distribution-based MID estimates provided a range of MID values for each of the four items, the three sections and the total score of the MSQPT. The MID values were tested for their sensitivity and specificity for amelioration and deterioration for each of the four items, the three sections and the total score of the MSQPT. The MID values of each item and section and of the total score with the best sensitivity and specificity were selected as thresholds for clinical change.
The outcome measures were the MSQPT, Hamburg Quality of Life Questionnaire for Multiple Sclerosis (HAQUAMS), rating of change questionnaires, Expanded Disability Status Scale, 6-metre timed walking test, Berg Balance Scale and 6-minute walking test.
The effect size ranged from 0.46 to 1.49. The SRM data showed comparable results. The modified SRM ranged from 0.00 to 0.60. Anchor-based MID estimates were very low and were comparable with SD- and SEM-based estimates. The MSQPT was more responsive than the HAQUAMS in detecting improvement but less responsive in finding deterioration. The best MID estimates of the items, sections and total score, expressed in percentage of their maximum score, were between 5.4% (activity) and 22% (item 10) change for improvement and between 5.7% (total score) and 22% (item 10) change for deterioration.
The MSQPT is a responsive questionnaire with an adequate MID that may be used as threshold for change during rehabilitation of MS patients.
This trial was retrospectively (01/24/2015) registered in ClinicalTrials.gov as NCT02346279.
Van der Maas NA, Biland-Thommen U, Grillo JT. Die Valididität, Reliabilität und Akzeptanz des Multiple Sclerosis Questionnaire for Physiotherapists (MSQPT). Physioscience. 2010;5:135–42. CrossRef
Van der Maas NA, Steinlin Egli R. Evaluation des subjektiven Gesundheitszustandes von MS-Patienten in physiotherapeutischer Behandlung: Multiple Sclerosis Questionnaire for Physiotherapists®(MSQPT®). In: Schädler S et al., editors. Assessments in der rehabilitation, band 1: neurologie. 3rd ed. Bern: Verlag Hans Huber; 2012. p. 532–9.
Bortz J, Döring N. Forschungsmethoden und evaluation für human- und sozialwissenschaftler. 3rd ed. Berlin Heidelberg New York: Springer; 2003. p. 180–1.
Wirtz M, Caspar F. Beurteilerübereinstimmung und Beurteilerreliabilität. Göttingen Bern Toronto Seattle: Hogrefe-Verlag; 2002. p. 123–7.
Fitzpatrick R, Davey C, et al. Evaluating patient-based outcome measures for use in clinical trials. Health Technol Assess. 1998;2(14):i–iv. 1-74. PubMed
Norman, et al. Interpretation of changes in health-related quality of Life; the remarkable universality of half a standard deviation. Med Care. 2003;41(5):582–92. PubMed
Middel B, van Sonderen E. Statistical significant change versus relevant or important change in (quasi) experimental design: some conceptual and methodological problems in estimating magnitude of intervention-related change in health services research. Int J Integr Care. 2002;2:e15. CrossRefPubMedPubMedCentral
Latzel G, Fischbacher Schrobiltgen E. Multiple Sklerose in der Schweiz. In: Die Lebensbedingungen von MS-Betroffenen und die finanziellen Folgen ihrer Krankheit. Zürich: Schweizerische MS-Gesellschaft Zürich; 2001.
- Patient-reported questionnaires in MS rehabilitation: responsiveness and minimal important difference of the multiple sclerosis questionnaire for physiotherapists (MSQPT)
Nico Arie van der Maas
- BioMed Central