Current data collected by medical examiners and coroners are incomplete and inadequate to evaluate the factors that lead to fatalities involving prescription opioids. Determining cause of death is critically important. Two methods are proposed to improve consistency and accuracy in the collection and analysis of decedent data in opioid-related poisoning deaths. First, an improved death certificate is needed to collect evaluative data, including: extent to which opioids were judged to 1) cause, 2) contribute to, or 3) be present in investigated deaths; extent to which opioids as a cause of death were found 1) alone, 2) combined with other prescription drugs, 3) combined with alcohol, or 4) combined with illicit drugs; the time of death; the presence or absence of a valid prescription; and the estimated quantity of opioids taken proximal to death. Patient characteristics for analysis include age, gender, race/ethnicity, geographic area (particularly whether urban or rural), body mass index, duration of opioid usage and daily average dose during the last 2 weeks of life, and histories of chronic pain/medical conditions, substance abuse, and mental illness/psychiatric diagnoses. Second, expanding the scope of opioid toxicology categories used to classify and code cause-of-death data reported by death investigators would improve identification of individual drugs and classes most often associated with overdose deaths. Formulation-specific codes should be added to facilitate consistent recording of findings by death investigators and entry into national vital statistics databases.