A measure of perceived stigma in people with intellectual disability.

BACKGROUND There is a lack of validated instruments measuring perceived stigma in people with intellectual disability. AIMS To develop a valid and reliable self-rated instrument to measure perceived stigma that can be completed by people with mild to moderate intellectual disability. METHOD A literature search was used to generate a list of statements. Professionals, individuals with intellectual disability and carers were consulted about the suitability of statements. An instrument was developed containing statements about stigma with accompanying photographs. Test-retest reliability, internal consistency and the factor structure of the instrument were evaluated. RESULTS The instrument was completed by 109 people once and 88 people twice. Items with limited variability in responses and kappa coefficients lower than 0.4 were dropped. Exploratory factor analysis revealed two factors: ;perceived discrimination' (seven items) and ;reaction to discrimination' (four items). One item loaded onto both factors. Cronbach's alpha for the ten-item instrument was 0.84. CONCLUSIONS This instrument will further our understanding of the impact of stigma in people with intellectual disability in clinical and research settings.