This study aims to determine risk factors of opioid overdose among the Colorado Medicaid
population. A retrospective nested case-control study was undertaken. Medicaid
beneficiaries who had≥ 1 medical claim for an emergency department visit or a
hospitalization associated with an opioid overdose from July 2009 to June 2014 were
defined as cases. Controls were selected using a nearest neighbor matching without
replacement. The matched controls were selected on the basis of age, sex, and opioid …