Can the Expanded Disability Status Scale be assessed by telephone?
Information from patients who are unable to continue their visits to a study centre may be of major importance for the interpretation of results in multiple sclerosis (MS) clinical trials. To validate a questionnaire based on the Expanded Disability Status Scale (EDSS), patients in five different European centres were assessed independently by pairs of trained EDSS raters, first by telephone interview and a few days later by standardized neurological examination. Seventy women and 40 men with an average age of 43.7 years (range 19-74 years) were included in the study. Mean EDSS score at the last visit was 4.5 (0-9). EDSS assessment by telephone was highly correlated with the EDSS determined by physical examination (Pearson's correlation coefficient = 0.95). An intraclass correlation coefficient (ICC) of 94.8% was found for the total sample; 77.6% and 86%, respectively, for patients with EDSS < 4.5 (n = 46) and > 4.5 (n = 64). Kappa values for full agreement were 0.48; for variation by +0.5 steps and +1.0 steps, 0.79 and 0.90, respectively. Best agreement could be found in higher EDSS scores, where assessment by telephone interview might be needed most. The telephone questionnaire is a valid tool to assess EDSS score in cases where the patient is unable to continue visiting a study centre or in long-term follow-up of trial participants.
Lechner-Scott
J
J
Department of Neurology, Kantonspital Basel, Switzerland.
Kappos
L
L
Hofman
M
M
Polman
C H
CH
Ronner
H
H
Montalban
X
X
Tintore
M
M
Frontoni
M
M
Buttinelli
C
C
Amato
M P
MP
Bartolozzi
M L
ML
Versavel
M
M
Dahlke
F
F
Kapp
J-F
JF
Gibberd
R
R
D000328:Adult; D000368:Aged; D004185:Disability Evaluation; D005060:Europe; D005260:Female; D006801:Humans; D007407:Interviews as Topic / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis*; D015203:Reproducibility of Results; D016138:Walking