Reliability and validity of a short version of the STAI anxiety measurement scale in respiratory patients.

BACKGROUND There is comorbidity between respiratory disease and anxiety. In order to measure the anxiety of hospitalized patients it is necessary to use reliable and valid, and preferably short questionnaires. OBJECTIVE To analyze the reliability and validity of a shortened version of the state subscale of the “State-Trait Anxiety Inventory (STAI)” in respiratory patients. PATIENTS AND METHODS A total of 103 respiratory patients admitted to the respiratory ward between February of 2009 and February of 2010 were non-consecutively selected. They answered two questionnaires: the Spanish version of the STAI-state and a short version consisting of 7 items. Sociodemographic and clinical variables of the patients were also obtained. The internal consistency, and convergent and construct validity of the short scale were analyzed. RESULTS The short scale did not have floor/ceiling effect, the α-Cronbach was acceptable (0.89), and correlated positively (r = 0.90; P = .01) and also maintained the factorial structure of the original scale (half anxiety-present items and half anxiety-absent items). CONCLUSIONS The short version of the state subscale of the STAI has showed good metric properties in hospitalized respiratory patients.