The Functioning Assessment Scale for Mental Health: Development and validation.

BACKGROUND

The goal of this study was to develop and validate the Functioning Assessment Scale for Mental Health (FAS-MH), a multidimensional instrument grounded in the International Classification of Functioning, Disability, and Health (ICF). The FAS-MH is designed to assess key functioning domains and environmental factors in individuals with mental disorders.

METHODS

The development process involved item generation in both Spanish and English, followed by content validation through a two-round Delphi survey with expert panels (20 and 12 professionals, respectively). The Spanish version was then tested in a sample of 334 adults diagnosed with bipolar disorder, depression, or schizophrenia to examine its dimensional structure, internal consistency, and relationships with other variables.

RESULTS

The final 37-item scale covers 34 second-level ICF categories across three domains: Body Functions, Activities and Participation, and Environmental Factors. Confirmatory factor analysis supported a hierarchical model with four first-order factors and one second-order Functioning factor. The FAS-MH showed excellent internal consistency (α = 0.85-0.95; ω = 0.90-0.96) and moderate to strong correlations with established measures of disability, health status, and quality of life.

LIMITATIONS: Content validation was based on a small sample, only the Spanish version of the FAS-MH was tested psychometrically, and associations with clinical outcomes, symptom severity, or clinician-rated assessments were not explored.

CONCLUSIONS

The FAS-MH is the first instrument to comprehensively incorporate all ICF components for assessing functioning in individuals with mental disorders. The Spanish version demonstrated strong psychometric properties, providing a brief and user-friendly tool for clinical and research use.