How common is seasonal affective disorder in temperate Australia? A comparison of BDI and SPAQ estimates.
BACKGROUND
The frequency of winter Seasonal Affective Disorder (SAD) in temperate Australia is unknown.


METHODS
A random community sample in Melbourne completed four waves of data collection (winter and summer across two years). The presence of winter SAD was estimated in three ways: (i) self-reports on the Seasonal Pattern Assessment Questionnaire (SPAQ), (ii) evidence of significant depression as assessed on the Beck Depression Inventory (BDI) in winters and not summers, and (iii) a combined definition based on both SPAQ and BDI estimates.


RESULTS
Of 1080 questionnaires originally mailed, complete four-wave BDI data was obtained from 380 respondents, and complete SPAQ data from 297. The frequency of winter SAD as estimated from SPAQ data was 0.7% and from BDI data was 0.5%. One participant (1 of 297, 0.3%) met BDI criteria and approached caseness on SPAQ criteria.


CONCLUSIONS
A larger sample is necessary to definitively estimate prevalence.


CONCLUSIONS
Winter SAD appears to be rare in temperate Australia. The best estimate from the current study (0.3%) is an advance on simple self-report estimates and provides a necessary reference point for clinicians and researchers.
Murray
Greg
G
School of Social and Behavioural Sciences, Swinburne University of Technology, PO Box 218 John Street, Hawthorn, 3122, Australia. gwm@swin.edu.au
D000328:Adult; D000368:Aged; D001315:Australia; D002980:Climate; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D016574:Seasonal Affective Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D012621:Seasons