Spanish Language Translation and Initial Validation of the Functional Assessment of Cancer Therapy Quality-of-Life Instrument

Abstract
There is a need in the United States for culture-equivalent assessment of health-related quality of life, particularly among people who speak different languages and among those with low literacy skills. This report summarizes the adaptation of the Functional Assessment of Cancer Therapy(FACT) Scales for use with Spanish-speaking cancer patients, including those with low literacy. The Spanish language version of the general Functional Assessment of Cancer Therapy scale plus five disease-specific subscales (breast, lung, colorectal, head and neck, HIV infection) were translated, reviewed, and revised, then evaluated in interviews with Spanish-speaking patients from the mainland United States and Puerto Rico. An iterative forward-backward-forward sequence of item translation, expert bilingual/bicultural advisor review, pretesting interviews with 92 patients, and further expert advisory input were used to establish semantic, content, and partial technical equivalence. The Functional Assessment of Cancer Therapy-General and five disease-specific subscales were translated successfully into wording that was easily understood and answered, leading to psychometric and scoring data similar to that of the English version. All but one of the 28 Functional Assessment of Cancer Therapy-General items and all of the disease-specific items were seen as culturally relevant. The result is a document that underwent iterative forward-backward translation and evaluation and was pretested successfully with native Spanish-speaking oncology patients living in the Central United States and Puerto Rico. The Functional Assessment of Cancer Therapy-General and five disease-specific subscales have been translated successfully into Spanish using a thorough translation and initial validation methodology. The methods and data provide a model for preparing a health status questionnaire for cross-cultural validation. The questionnaire is available for use in clinical trials and clinical practice.