Sk. Raheja et al., THE SEASONAL PATTERN ASSESSMENT QUESTIONNAIRE FOR IDENTIFYING SEASONAL AFFECTIVE-DISORDERS, Journal of affective disorders, 41(3), 1996, pp. 193-199
The SPAQ is a widely used tool for identifying possible cases of recur
rent major depressive disorders with a seasonal pattern. However. its
test-retest reliability, sensitivity, specificity, positive predictive
value, negative predictive value, efficiency and predictive validity
have not previously been formally assessed. Forty-seven subjects who f
ulfilled the DSMIIIR criteria for a major depressive disorder with a s
easonal pattern were traced and re-interviewed after five to eight yea
rs. The SPAQ was found to have a positive predictive value of 48% and
an efficiency of 57% in identifying cases of SAD confirmed by follow-u
p. The test-retest reliability was low. There was a mean difference in
seasonality score between the first and second test of 3.17 +/- 4.7 (
mean +/- 1 S.D.). Although the SPAQ is a rapid method of collecting in
formation about recent seasonal variation, it has low test-retest reli
ability and on its own is unable to predict the seasonality of the fut
ure course of illness.