Abstract
STUDY OBJECTIVES: The current study investigated the factor structure of the Pittsburgh Sleep Quality Index (PSQI) among English speaking non-Hispanic whites (NHW) and English and Spanish speaking Hispanics of Mexican descent (HMD). DESIGN: The PSQI was administered during a telephone interview. In order to test the factor structure of the PSQI structure across ethnic/language groups, multiple group confirmatory analysis with covariates (MIMIC) was employed. The 1- and 3-factor versions of the PSQI previously reported in the literature were examined. SETTING: San Diego County. PARTICIPANTS: Community-dwelling English speaking, NHW (n = 1,698) and English (n = 654) and Spanish (n = 792) speaking HMD. MEASUREMENT AND RESULTS: A single-factor scoring model fit across language/ethnic groups; however, a 3-factor model provided a better than the 1-factor model in all language/ethnic groups. The subscale sleep medications loaded poorly and was removed from all models. CONCLUSION: Across groups, a 3-factor model of the PSQI more reliably assessed sleep quality than a single-factor global score. Results indicate that the 3-factor structure of the PSQI was uniform across English speaking NHW and English and Spanish speaking HMD.