Objective: The comprehensive ICF core set for multiple sclerosis (MS) is an application of the international classification of functioning, disability and health (ICF) and represents the typical spectrum of problems in functioning of people with MS (PwMS). The objective of this study was to validate this ICF core set from the perspective of occupational therapists (OTs).

Methods: In a three-round Delphi study, OTs were asked about problems and resources of PwMS, as well as environmental aspects treated by OTs. Statements were linked to the ICF and compared with the categories included in the comprehensive ICF core set for MS.

Results: Sixty-one OTs from 21 countries agreed on 71 categories that are included in the comprehensive ICF core set for MS (19 body functions, 40 categories of activities and participation, 12 environmental factors). Eleven ICF categories were identified as not-yet-included ICF categories in the comprehensive ICF core set for MS (6 body functions, 2 categories of Activities and participation, 3 environmental factors).

Conclusions: This study contributes to the validity of the ICF categories included in the comprehensive ICF core set. It outlines which areas of functioning and health are relevant for PwMS from the perspective of OTs and consequently should be assessed.