Objective: To report on results of a standardized consensus process agreeing on concepts typical and/or relevant when classifying functioning and health in patients with ankylosing spondylitis (AS) based on the International Classification of Functioning and Health (ICF).
Methods: Experts in AS from different professional and geographic backgrounds attended a consensus conference and were divided over three working groups. Rheumatologists were selected from the members of Assessment of SpondyloArthritis international Society (ASAS). Other health professionals were recommended by ASAS members. The aim was to compose three working groups with five to seven participants to allow everybody’s contribution in the discussions. Experts selected ICF categories that were considered typical and/or relevant for AS during a standardized consensus process by integrating evidence from preceding studies in alternating working group- and plenary discussions. A Comprehensive ICF Core Set was selected for the comprehensive classification of functioning and a Brief ICF Core Set for application in trials.
Results: The conference was attended by 19 experts from 12 countries. Eighty categories were included in the Comprehensive Core Set of which 23 body functions, 19 body structures, 24 activities and participation, and 14 environmental factors. Nineteen categories were selected for the Brief Core Set of which 6 body functions, 4 body structures, 7 activities and participation, and 2 environmental factors.
Conclusion: The Comprehensive and Brief ICF Core Sets for AS are now available and aim to represent the external reference to define consequences of AS on functioning.