Validating Imputation Procedures to Calculate Corrected Opioid-Involved Overdose Deaths, Marion County, Indiana, 2011-2016

Abstract

Objectives: Understanding the scope of the current opioid epidemic requires accurate counts of the number of opioid-involved drug overdose deaths. Given known errors and limitations in the reporting of these deaths, several studies have used statistical methods to develop estimates of the true number of opioid-involved overdose deaths. This study validates these procedures using a detailed county-level database of linked toxicology and vital records data. Methods: We extracted and linked toxicology and vital records data from Marion County, Indiana (Indianapolis), during a 6-year period (2011-2016). Using toxicology data as a criterion measure, we tested the validity of multiple imputation procedures, including the Ruhm regression-based imputation approach for correcting the number of opioid-involved overdose deaths. Results: Estimates deviated from true opioid-involved overdose deaths by 3% and increased in accuracy during the study period (2011-2016). For example, in 2016, 231 opioid-involved overdose deaths were noted in the toxicology data, whereas the corresponding imputed estimate was 233 opioid-involved overdose deaths. A simple imputation approach, based on the share of opioid-involved overdose deaths among all drug overdose deaths for which the death certificate specified ≥1 drug, deviated from true opioid-involved overdose deaths by ±5%. Conclusions: Commonly used imputation procedures produced estimates of the number of opioid-involved overdose deaths that are similar to the true number of opioid-involved overdose deaths obtained from toxicology data. Although future studies should examine whether these results extend beyond the geographic area covered in our data set, our findings support the continued use of these imputation procedures to quantify the extent of the opioid epidemic.

Jail and overdose: assessing the community impact of incarceration on overdose

“…Study data are from Marion County, IN, home to Indianapolis, which is the 12th largest city in the United States [42] and the largest county in a state that had the 18th highest mortality rate in 2017 of 25.6 per 100 000 population [43]. In 2017, the overdose rate in Marion County was 39.4 per 100 000 and accounts for greater than 20% of all the fatal overdoses in Indiana, with fentanyl-involved overdose deaths comprising more than half of all the overdose deaths [43,44]. Administrative records for jail bookings were related to a single jail site and obtained from the Marion County Sheriff 's Office (MCSO) and included booking date, release date and booking offense for all individuals who were detained from 1 January 2015 to 31 December 2019.…”

“…Administrative records for jail bookings were related to a single jail site and obtained from the Marion County Sheriff 's Office (MCSO) and included booking date, release date and booking offense for all individuals who were detained from 1 January 2015 to 31 December 2019. Accidental fatal overdose data came from the Marion County Coroner's Office (MCCO) that were collected as part of ongoing funding to the Indiana Department of Health (NU17CE002721-02 and CDC-RFA-CE19-1904) to collect real-time toxicology data and have been used to surveil trends in fatal overdose events [45][46][47], as well as document gaps in the death investigation process [43,44]. In this study we looked at all accidental overdose deaths confirmed by the MCCO occurring within the county from 1 January 2017 to 31 December 2019.…”

A modified two-process Knox test for investigating the relationship between law enforcement opioid seizures and overdoses

“…Toxicology data from Marion County, Indiana were used to measure fatal overdose events in this study. These data have been used to examine trends in fatal overdose events [24][25][26][27] and document gaps in the death investigation process [28,29]. Between 2014 and 2018, there were 1626 fatal overdoses with the peak number occurring in 2017 with 406 deaths.…”

Commentary on Boslett et al. (2020): Towards better measurement of drug involvement in fatal overdoses

“… address the first of these by extending prior adjustment approaches that use decedent information and limited county characteristics to predict drug involvement where specific information is not provided . These methods have been shown to yield more accurate measures of prevalence .…”

“…This has the further advantage of sometimes being feasible using only public use, rather than restricted, mortality data. Thus, this ‘naive’ method may be preferable if the loss of accuracy is not too great, as is sometimes the case .…”