General population surveys were used to determine the prevalence of drug use disorders in the US. The surveys, however, did not include significant demographic categories like the homeless and institutionalized people, and respondents could underreport their usage of drugs. For a study, researchers sought to determine how common drug use problems were in the US.
Based on information from the Transformed Medicaid Statistical Information System (T-MSIS), which served as the benchmark, and the National Survey on Drug Use and Health (NSDUH), which served as the multiplier, estimates of the prevalence of alcohol, cannabis, opioid, and stimulant use disorders were made for the years 2018 and 2019. T-MSIS gathered administrative information on Medicaid recipients receiving full or comprehensive benefits which are 12 years of age or older. The NSDUH was a yearly cross-sectional survey of individuals aged 12 and older that was conducted countrywide. Based on T-MSIS and NSDUH data, the prevalence of substance use disorders was calculated using the benchmark multiplier approach. Monte Carlo simulations were used to calculate the confidence ranges for multiplier method estimations. The responsiveness of prevalence estimations to changes in multiplier values was evaluated.
The study included Medicaid beneficiaries 12 years and older who received treatment services in the previous year for alcohol (n = 1,017,308 in 2018; n = 1,041,357 in 2019), cannabis (n = 643,737; n = 644,780), opioid (n = 1 406,455; n = 1,575,219), and stimulant (n = 610,858; n = 657,305) use disorders, and NSDUH participants with 12-month DSM-IV alcohol (n = 3,390 in 2018; n = 3,363 in 2019), cannabis (n = 1,426; n = 1,604), opioid (n = 448; n = 369), & stimulant (n = 545; n = 559) use disorders. For every type of substance use disorder in both years and the combined 2018 to 2019 sample, the benchmark multiplier prevalence estimates were higher than the NSDUH estimates: for alcohol, 20.27% (95% CI, 17.04-24.71) vs. 5.34% (95% CI, 5.10-5.58), respectively; for cannabis, 7.57% (95% CI, 5.96-9.93) vs. 1.68% (95% CI, 1.59-1.79); for opioids, 3.46% (95% CI, 2.97-4.12) vs. 0.68% (0.60-0.78) and 1.91% (95% CI, 1.63-2.30) vs. 0.85% (95% CI, 0.75-0.96) for stimulant use disorders. The benchmark multiplier approach and NSDUH estimates differed in sensitivity analysis across a wide range of possible multiplier values.
The study results indicated that drug use disorders were more prevalent nationally than the NSDUH estimates indicate, indicating a heavier burden of these illnesses in the US.