OBJECTIVE: The authors estimated the frequency of seasonal affective disorder in children and adolescents and examined the relationship of this rate to age and pubertal status. METHOD: A modified version of the Seasonal Pattern Assessment Questionnaire was distributed to 2,267 students at a middle school and a high school in a suburb of Washington, D.C. A case diagnosis was made if the respondent scored over 18 and also indicated that the change of seasons was at least a "pretty bad" problem. RESULTS: A total of 1,871 questionnaires (82.5%) were returned. Sixty probable cases of seasonal affective disorder (3.3%) were identified among the 1,835 surveys analyzed. Age was directly correlated with the frequency of seasonal affective disorder, and the rate was higher in postpubertal girls. Differences between the subjects with and without identified cases of seasonal affective disorder were seen in the symptom endorsement patterns, particularly for "feel worst," "least energy," "most irritable," and "socialize least." CONCLUSIONS: These pilot data suggest that between 1.7% and 5.5% of 9-19-year-old children may have seasonal affective disorder. Further research is warranted, particularly that which examines the relationship between seasonal affective disorder and puberty.Abstract Teaser