Multiple sclerosis functional composite: impact of reference population and interpretation of changes

Abstract

The Multiple sclerosis functional composite (MSFC) has been recommended as a clinical outcome measure to be used in future MS trials. A specific characteristic of the MSFC is that it is defined as a measure of impairment relative to a reference population. Using different reference populations affects actual MSFC scores. If the selection of a reference population also has an effect on sensitivity to change of the MSFC, comparison of data from clinical trials will be almost impossible when different reference populations are used We studied the effect of the selection of a reference population on the outcome of a trial by simulating 343 intervention trials and comparing results obtained by using three different reference populations: two previously published MS patient populations and a healthy population. Scores of the healthy population were collected in the first part of the study. The effects of sex, age and education level on test scores of healthy subjects were studied as well. In the healthy controls, sex, age and education level had a different impact on individual test scores of MSFC components and overall MSFC score. Our study shows that, with the use of the MSFC, the selection of different reference populations does not affect the trial statistics and significance, but it does affect comparability of results between different trials, and complicates the dinical interpretation of any observed change.

Long–term exercise improves functional impairment but not quality of life in multiple sclerosis

“…The wide variation in MSFC changes over different studies is probably related to differences in the type and length of the intervention. On the other hand, it has been shown that the use of different reference populations has an effect on Zscores and, consequently, on MSFC scores [37]. Like Cohen et al [5], we applied an internal reference population where the means and standard deviations of the None of the differences between groups were significant either at baseline (p > 0.1) or at 6 months (p > 0.2) Table 3 MSQOL-54 scale scores (mean ± SD) of the two study groups and magnitude of change (effect size) in each scale baseline measurements for all study patients were used.…”

Padronização da Multiple Sclerosis Functional Composite Measure (MSFC) na população brasileira

“…Nossos resultados demonstraram que no 25-F W o escore dos homens é significantemente maior se comparado com as mulheres, resultados estes semelhantes aos encontrados na população alemã 17 .…”

“…Com relação ao PA S AT, não observamos diferenças significantes no teste de 3 segundos, porém no teste de 2 segundos observamos melhor desempenho dos indivíduos de sexo masculino e naqueles com maior escolaridade, embora autores atribuam a correlação deste teste ao QI dos pacientes 21 é bem demonstrada a interferência da escolaridade no desempenho final 17 .…”

Physical and Cognitive Functioning After 3 Years Can Be Predicted Using Information From the Diagnostic Process in Recently Diagnosed Multiple Sclerosis

“…20 Impaired dexterity was defined as an abnormal score (mean -1.96 SD, healthy Dutch reference population) for the 9-Hole Peg Test. 21 Cognitive impairments were defined as a score of mean -SD for 1 or more subtests of a cognitive screening test that was specifically developed for MS, which includes the subscales Consistent Long Term Retrieval and Long Term Storage of the Selective Reminding Test measuring verbal learning and memory, the 10/36 Spatial Recall Test measuring visuospatial learning and delayed recall, the Symbol Digit Modalities Test measuring sustained attention and concentration, the Paced Auditory Serial Addition Test measuring sustained attention and information processing speed, and the Word List Generation measuring verbal fluency. [22][23][24] Incontinence was defined as a score of 5 or lower for the continence item of the FIM.…”