The reliability and validity of the Nottingham Extended Activities of Daily Living Scale in patients with multiple sclerosis
Objective: To investigate whether the Nottingham Extended Activities of Daily Living Scale (EADL) is reliable and valid for the assessment of disability in patients with multiple sclerosis (MS). Design: Questionnaire measures were administered on two occasions four months apart. Subjects: A total of 240 patients recruited through a randomized controlled trial of cognitive assessment and treatment in MS. Measures: The Nottingham EADL, Guys Neurological Disability Scale (GNDS) and SF-36 quality of life scale. Results: The EADL items did not form a Guttman Scale (CR 0.8, CS 0.3). The EADL and its four subscales all had high internal consistency (α 0.72-0.94). Test-retest reliability was satisfactory (rs 0.81-0.90) with a mean difference in scores on the two occasions of 0.29. Factor analysis generally supported the subscale structure. There were significant but weak correlations with quality of life measures. Conclusions: The EADL shows promise for the assessment of disability in MS, but the range of items needs to be extended. Further evaluation of the scale seems warranted.