The proposed research has two major goals. The first goal is to assess seasonal influences in self-reports of the past 30-day, past 12-month, and lifetime alcohol or drug use in a year-long needs assessment survey of the adult population of Washington State. Significant findings will support further investigation of seasonal effects at the regional or national scale. The second goal is to identify and model geophysical correlates of the seasonal bias in reported use. The modeling effort will pursue a method for adjusting self-report of substance use based upon seasonal or climatic effects. Washington, as a northern state, is an excellent location to explore seasonal influences since seasons are more exaggerated at higher latitudes. This will be the first state, regional, or national study to evaluate and model seasonal effects in the self-report of substance use in a general population survey. Core research questions include: 1) What are the seasonal patterns in the self-report of past-month, past-year, and lifetime substance use? 2) How do seasonal patterns of recent and historical reported use vary with: a) sociodemographic factors such as gender, ethnicity, poverty status, urban/rural status, social environment (i.e. family or community risk factors), or age cohort; and b) type of substance and severity of individual use? 3) How do seasonally varying rates correlate to geophysical data (i.e. average day length, sky cover, temperature, etc.)? 4) How do seasonal patterns of recent and historical reported use vary with reported affective disorders including unipolar and bipolar depression, generalized anxiety disorder, and panic? 5) Is there justification for adjusting self-report of substance use to account for seasonal influences and, if so, what procedures are worthy of future research? The database of survey respondents comes from The Washington State Needs Assessment Household Survey (WANAHS), a telephone survey designed to develop a common information base by asking the same clinically tested questions of a stratified random sample of over 7,000 adults in the state of Washington. Survey domains covered disability status, recency and frequency of substance use, DSM-III-R substance abuse and dependence, treatment history and treatment need, risk factors associated with problem use, and DSM-III-R depression, generalized anxiety and panic, mania, and psychosis. A stratified sampling design was used to obtain purposive oversamples of persons in poverty, rural residents, women, and minorities including Blacks, Asians, Native Americans, and Hispanics. The survey was implemented over a 14-month period to control for seasonal effects in responses and to analyze seasonal effects upon completion. Considerable effort was made to reduce non-response, leading to 81% of all eligible adult respondents completing an interview. Climate data available on a daily basis during the period of the survey include: hours of daylight, hours of direct sun, sky cover, average temperature, inches of precipitation, average wind speed, and others.
