An examination of the "gold standard" diagnosis of major depression in aged-care settings.
OBJECTIVE
Individual clinical interviews are typically viewed as the "gold standard" when diagnosing major depressive disorder (MDD) and when examining the validity of self-rated questionnaires. However, this approach may be problematic with older people, who are known to underreport depressive symptomatology. This study examined the effect of including an informant interview on prevalence estimations of MDD in an aged-care sample.


METHODS
The results of an individual clinical interview for MDD were compared with those obtained when an informant interview was incorporated into the assessment. Results from each diagnostic approach were compared with scores on a self-rated depression instrument.


METHODS
Low-level aged-care residential facilities in Melbourne (equivalent to "residential homes," "homes for the elderly," or "assisted living facilities" in other countries).


METHODS
One hundred and sixty-eight aged-care residents (mean age: 84.68 years; SD: 6.16 years) with normal cognitive functioning.


METHODS
Individual clinical interviews were conducted using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders. This interview was modified for use with staff informants. Self-reported depression was measured using the Geriatric Depression Scale-15 (GDS-15).


RESULTS
The estimated point prevalence of MDD rose from 16% to 22% by including an informant clinical interview in the diagnostic procedure. Overall, 27% of depressed residents failed to disclose symptoms in the clinical interview. The concordance of the GDS-15 with a diagnosis of MDD was substantially lower when an informant source was included in the diagnostic procedure.


CONCLUSIONS
Individual interviews and self-report questionnaires may be insufficient to detect depression among older adults. This study supports the use of an informant interview as an adjunct when diagnosing MDD among cognitively intact aged-care residents.
Davison
Tanya E
TE
School of Psychology, Deakin University, Melbourne, Australia. tanya.davison@deakin.edu.au
McCabe
Marita P
MP
Mellor
David
D
D000368:Aged; D000369:Aged, 80 and over; D017028:Caregivers; D003863:Depression / Q000175:diagnosis* / Q000523:psychology; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D015577:Geriatric Assessment; D006707:Homes for the Aged; D006801:Humans; D007406:Interview, Psychological / Q000379:methods*; D008297:Male; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D015203:Reproducibility of Results