Test characteristics of the 15-item geriatric depression scale and Hamilton depression rating scale in Parkinson disease.
OBJECTIVE
The objective of this study was to compare the sensitivity, specificity, and diagnostic accuracy of the 15-item Geriatric Depression Scale (GDS-15) and the Hamilton Depression Rating Scale (HDRS) in patients with Parkinson disease (PD).


METHODS
A convenience sample of 148 outpatients with idiopathic PD receiving specialty care completed the GDS-15 and were administered the HDRS and Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID) depression module by a research psychiatrist or trained research assistant. Receiver-operating characteristic (ROC) curves were plotted for the GDS-15 and HDRS scores with a SCID diagnosis of a depressive disorder as the state variable.


RESULTS
Thirty-two subjects (22%) were diagnosed with a depressive disorder. The discriminant validity of the GDS-15 and HDRS were both high (ROC area under the curve: 0.92 and 0.91, respectively), with greatest dichotomization for the GDS-15 at a cutoff of 4/5 (87% accuracy, 88% sensitivity, 85% specificity) and the HDRS at a cutoff of 9/10 (83% accuracy, 88% sensitivity, 78% specificity).


CONCLUSIONS
The GDS-15 performs well as a screening instrument and in distinguishing depressed from nondepressed patients in PD. Its test characteristics are comparable to the HDRS. Because it is a brief instrument and can be self-administered, it is an excellent depression screening tool in this population.
Weintraub
Daniel
D
Department of Psychiatry, University of Pennsylvania, and the Parkinson's Disease Research, Education and Clinical Center, Philadelphia Veterans Affairs Medical Center 19104, USA. weintrau@mail.med.upenn.edu
Oehlberg
Katherine A
KA
Katz
Ira R
IR
Stern
Matthew B
MB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000453:epidemiology*; D012372:ROC Curve; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires