- Baseline questionnaire completed by about 225,000 participants
- More than 930 variables describing social and economic demographics, personal and family health histories, medications, sleep patterns, alcohol and tobacco use, physical activity and environmental exposures.
- Regular follow-up questionnaires will be conducted to track changes in overall health
The OHS concluded its first follow up questionnaire in March 2018. The questionnaire asked participants to provide an update on their health. It also had additional questions around e-cigarettes and marijuana use, mental health and over-the-counter drugs.