Responsiveness of patient-based and external rating scales in multiple sclerosis: Head-to-head comparison in three clinical settings
Received 7 May 2009; received in revised form 6 October 2009; accepted 21 October 2009. published online 18 November 2009.
Abstract
Background
Patient-based rating scales and especially quality of life scales have received increasing attention as secondary outcome measures in multiple sclerosis (MS). Responsiveness to health-related change of quality of life scales is thus an important property when these measures are to be used successfully in clinical trials.
Methods
We conducted an analysis of 3 cohorts of MS patients to examine responsiveness of the Hamburg Quality of Life Questionnaire for Multiple Sclerosis (HAQUAMS). One cohort consisted of patients from the outpatient clinic whose overall health status deteriorated over the course of one year (n=53), one study investigated two neurorehabilitation programs (n=20 each) and a third study investigated a low-level aerobic fitness training intervention (n=15).
Results
The total score of the HAQUAMS and several subscales was found to be responsive in all three settings. In addition, we provide minimally important difference (MID) estimates based on anchor- and distribution-based methods for all scales of the HAQUAMS.
Conclusions
The HAQUAMS is responsive to change in observational and intervention studies in MS in adequately powered trials.
aInstitute of Neuroimmunology and Clinical MS-Research (INiMS), University Hospital Eppendorf, Martinistrasse 52, Hamburg, Germany
bInstitute of Medical Psychology, Center for Psychosocial Medicine, University Hospital Eppendorf, Martinistrasse 52, Hamburg, Germany
cDepartment of Hepatobiliary Surgery, Center for Transplantation Medicine, University Hospital Eppendorf, Martinistrasse 52, Hamburg, Germany
dDepartment of Neurology, UCLA School of Medicine, 635 Charles Young Dr S, Los Angeles, CA, USA
Corresponding author. Multiple Sclerosis Program, Dept Neurology, University of California Los Angeles, 635 Charles Young Dr S, Rm 479, Los Angeles, CA 90095, USA. Tel.: +1 310 206 4640; fax: +1 310 206 7282.
ABSTRACT