Validation of the International Classification of Functioning, Disability and Health Core Set for chronic widespread pain from the perspective of fibromyalgia patients

Introduction Functioning is recognized as an important study
outcome in chronic widespread pain (CWP). The Comprehensive ICF
Core Set for CWP is an application of the International
Classification of Functioning, Disability and Health ( ICF) with
the purpose of representing the typical spectrum of functioning of
patients with CWP. The objective of the study was to add evidence
to the validation of the Comprehensive ICF Core Set for CWP from
the patient perspective. The specific aims were to explore the
aspects of functioning and health important to patients with
fibromyalgia, and to examine to what extent these aspects are
represented by the current version of the Comprehensive ICF Core
Set for CWP. Methods The sampling of patients followed the maximum
variation strategy. Sample size was determined by saturation. The
focus groups were digitally recorded and transcribed verbatim. The
meaning condensation procedure was used for qualitative data
analysis. After qualitative data analysis, the identified concepts
were linked to ICF categories. Results Thirty-three patients
participated in six focus groups. Fifty-four ICF categories out of
67 categories of the Comprehensive ICF Core Set for CWP were
reported by the patients. Forty-eight additional categories that
are not covered in the Comprehensive ICF Core Set for CWP were
raised. Conclusions Most ICF categories of the existing version of
the Comprehensive ICF Core Set for CWP could be confirmed from the
patient perspective. However, several categories not included in
the Core Set emerged and should be considered for inclusion.