The International Classification of Functioning, Disability and Health Core Set for deafblindness. Part I: a systematic review of outcome measures.

The International Classification of Functioning, Disability, and Health (ICF), developed by the World Health Organization, is a classification framework that focuses on the health and functioning of people with disabilities. As part of an ICF Core Set development, four studies need to be conducted, one of which is a systematic review. This study presents part 1 of the systematic review that aims to describe the outcome measures identified in the literature related to functioning in individuals with deafblindness. The research team screened articles from eight scientific databases, three journals, and Google Scholar (March 2011 to September 2022). Articles were included if they studied individuals with deafblindness aged 18 and older. Studies that examined genetics or laboratory experiments involving animals were excluded. Data were extracted into a logbook with key descriptors such as study location and design, age of study population, and instruments/outcome measures used, which were further categorized into one of the following types: 1) standardized; 2) patient-reported measures, standardized (PT-S); 3) patient-reported measures, not standardized (PT-not S); 4) health professional, reported measures, standardized (HP-S); 5) Technical measures; 6) other measures (parent-reported standardized and laboratory measures). The review included 147 studies, of which most were conducted in Europe (47.6%) and North America (27.9%). Of the 314 identified outcome measures, 57 were Standardized, 59 were Patient Reported-Standardized (PT-S), 178 were patient reported non-standardized (PT-Not S) variables, 11 were health professional reported, standardized, five were technical, and four were classified as other measures. Most instruments measured functioning in daily activities and the mental health of individuals with deafblindness. Three deafblind-specific instruments were identified in this study, highlighting the need for more deafblind-specific instruments to be developed and utilized in research.