RT Journal Article SR Electronic T1 Public health responses to the opioid crisis in North America JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP jech-2018-210599 DO 10.1136/jech-2018-210599 A1 Thomas Kerr YR 2019 UL http://jech.bmj.com/content/early/2019/02/05/jech-2018-210599.abstract AB