[Validation of the Informed Choice instrument for Chilean women facing a mammography decision in primary care]. / Validación del instrumento Informed Choice para medir la decisión informada de mamografía en mujeres chilenas usuarias de atención primaria.

OBJECTIVE: To adapt and validate for the Chilean context the instrument Informed Choice (IC) to measure informed decision for mammography. LOCATION: Primary Health Care Center in southeast Santiago, Chile. DESIGN: Individual, transversal, analytical and psychometric adaptation and validation study. METHODS: We 1) translated and back-translated IC; 2) conducted a focus group for cultural/linguistic relevance; 3) reviewed content validity; 4) piloted the instrument; 5) applied IC for validation. Analysis was performed by using Cronbach alpha, correlation, Bartlett's test of sphericity, Kaiser-Meyer-Olkin measure and factor analysis. RESULTS: Three versions of the IC were developed, which included changes according to the views of users and experts. Validation was conducted in a sample of 70 women. Mean age was 54,4 years, 47,1% had completed secondary school and 92,9% have had at least one mammography. After factor analysis item 1 was removed and the final Cronbach Alpha was 0,79. CONCLUSIONS: The Chilean IC is reliable to measure decision women for mammography, this evaluate knowledge, attitude and intention towards the screening. The validation of an instrument to the cultural context is necessary and may have any variations to the original version according to local needs.