Development and initial validation of a 15-item informant version of the Geriatric Depression Scale.

OBJECTIVE To develop a brief informant version of the Geriatric Depression Scale for use in screening for depression in older adults. DESIGN A scale development and validation study. SETTING Internal medicine and geriatric outpatient clinics located at the James A. Haley Veterans' Medical Center and the University of South Florida Medical Center, Tampa, Florida. PARTICIPANTS A total of 147 patients (81 females and 66 males) and their adult informants. MEASUREMENTS Self and informant versions of the 30-item Geriatric Depression Scale, NEO-FFI, and a health behaviors questionnaire. RESULTS The 15-item informant version of the GDS was found to have sufficient internal consistency reliability (alpha = 0.86) and retest reliability (r = 0.81) to support its use as a clinical instrument. Construct validity was demonstrated by a pattern of correlations with external demographic and personality variables consistent with those of other versions of the GDS, as well as substantive correlations with these other versions. Efficacy of the GDSI-15 was found to be as good as that for the full 30-item informant version of the GDS. CONCLUSIONS The GDSI-15 may be a useful adjunct or alternative to standard screening methods in assessing patients in outpatient settings.