Validation of the Geriatric Depression Scale for an elderly Sri Lankan clinic population

Geriatric Depression Scale (GDS) has not been validated for the elderly population in Sri Lanka.

To translate, validate, and examine the effectiveness of GDS and to suggest the optimal cut-off scores for elderly Sri Lankans attending a psychogeriatric clinic.

The Sinhalese translation of GDS (GDS-S) was administered to people aged 55 years and above, attending a psychogeriatric outpatient clinic. The diagnostic performance of the instrument was compared against the ICD 10 diagnosis of a consultant psychiatrist, which was considered the 'gold standard'. Receiver operating characteristic (ROC) analysis was carried out to compare the diagnostic performance of the GDS-S. Optimal cut-off scores for depression and sensitivity and the specificity of the instrument was determined.

A total of 60 subjects formed the final sample (male/female=16/44) of which 30 were depressed, while 30 were age- and sex-matched controls. The optimal cut-off score for GDS-S was 8 for differentiating non-depressed from mildly depressed, while the cut-off score for moderate depression was 10. Sensitivity and specificity of GDS-S was 73.3% for differentiating depressed from non-depressed.

GDS is culturally acceptable, easy to use, sensitive, and a valid instrument to diagnose depression and to differentiate mild from moderate depression in an elderly Sri Lankan clinic population.