Psychometric characteristics of the Pittsburgh Sleep Quality Index in English speaking non-Hispanic whites and English and Spanish speaking Hispanics of Mexican descent.

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.