Validation of the Comprehensive and Brief International Classification of Functioning, Disability and Health Core Sets for Schizophrenia from the Perspective of Individuals Diagnosed with the Disorder: A Worldwide Study Using Focus Groups

The comprehensive and brief International Classification of Functioning, Disability and Health (ICF) core sets for schizophrenia, based on the World Health Organization (WHO) framework, aim to describe the functioning of individuals with schizophrenia. The objective of this study was to identify the most common problems faced by these individuals and validate the ICF core sets. Eight focus groups were conducted, recorded, and transcribed verbatim. The linking process involved two independent coders identifying meaningful units and linking agreed-upon concepts to the ICF categories. Data saturation was defined as the point at which no new categories emerged from additional focus groups. The 37 participants in this study represented the WHO regions of Africa, South-East Asia, the Western Pacific, and Europe. The focus groups confirmed the relevance of all ICF core set categories, with an additional 21 second-level categories being proposed in at least six of the eight focus groups. In this study, the ICF core sets for schizophrenia were validated from the perspective of individuals. However, several second-level categories not currently included in the ICF core sets also emerged. To ensure that the ICF core sets are truly international in scope, the potential relevance of these categories should be investigated further.