Seasonality in a community sample of bipolar, unipolar and control subjects

BACKGROUND: This study examined seasonality in a community sample of five diagnostic groups: normal subjects, those with non-seasonal depression (NSD), seasonal depression (SD), non-seasonal bipolar disorder (NSBD) and seasonal bipolar disorder (SBD). METHODS: Telephone interviews were conducted across the Province of Ontario. Seasonal changes in mood and behaviour were determined using the Seasonal Pattern Assessment Questionnaire (SPAQ). Five …