Validation of the International Classification of Functioning, Disability and Health (ICF) core set for diabetes mellitus from the patient perspective using focus groups

AIMS: The Comprehensive ICF Core Set for diabetes mellitus (DM) is a specific application of the International Classification of Functioning, Disability and Health (ICF) of the World Health Organization for clinical and research purposes involving the disorder. It represents the typical spectrum of functional problems in patients with DM. The objective of the study was to validate the Comprehensive ICF Core Set for DM from the perspective of patients. The specific aims were to explore the aspects of function and health important to patients with DM using focus group methodology and to examine to what extent these aspects are represented by the Comprehensive ICF Core Set for DM. METHODS: A qualitative study using focus group methodology was conducted. Sampling of patients followed the maximum variation strategy. Sample size was determined by saturation. The focus group discussions were digitally recorded and transcribed verbatim. The meaning condensation procedure was used for data analysis. The resulting meaningful concepts were linked to ICF categories according to established linking rules. RESULTS: Forty patients participated in eight focus groups. Seventy-five of the 85 ICF categories contained in the Comprehensive ICF Core Set for DM were identified by the patients. Forty-seven additional categories that are not covered by the Comprehensive ICF Core Set for DM were identified. CONCLUSIONS: The Comprehensive ICF Core Set for DM could be largely confirmed by the focus groups. Categories currently not covered by the Comprehensive ICF Core Set for DM should be investigated further.