Suicidal Thoughts, Plans, and Attempts by Non-Metropolitan and Metropolitan Residence. Using 2010-2016 data from the National Survey on Drug Use and Health, researchers from the Rural and Underserved Health Research Center found that the overall mean prevalence of suicidal thoughts among adults was significantly higher for non-metropolitan and small metropolitan counties. This page on the Rural Health Research Gateway contains links to additional research on illicit drug and opioid use disorders in rural areas.