Corrigendum to “Cost and cost-effectiveness of abstinence contingent wage supplements” [Drug Alcohol Depend. 244 (2023) 109754] (Drug and Alcohol Dependence (2023) 244, (S0376871622004914), (10.1016/j.drugalcdep.2022.109754))

It recently came to the authors attention that they made errors in the calculation of the incremental cost-effectiveness ratios (ICERs). An error was made converting ICERs to the incremental cost per participant. The cost analyses that underlie these calculations are unchanged. The authors describe below changes to the tables and figures that reflect the correct ICERs, and also note how the revised ICERs change their interpretation of the cost-effectiveness of the interventions. The authors would like to apologise for any inconvenience caused. The ICERs reported in Tables 4, 5 and 6 are incorrect. In the tables below, the authors summarize the published and corresponding corrected version of the ICERs. Corrected ICERs for Table 4, Intervention Costs per Participant [Table presented] Corrected ICERs for Table 4, Total Participant Costs [Table presented] Corrected ICERs for Table 5, Total Participant Costs [Table presented] Corrected ICERs for Table 6, Intervention Costs per Participant [Table presented] Corrected ICERs for Table 6, Total Participant Costs [Table presented] In the discussion, the authors included a paragraph which reviewed the total participant cost ICERs at the end of the 12-month study period. The corrected ICERs are substantially larger than the published ICERs and they do change their conclusions. To consider the adoption of ACWS as a cost-effective choice, policy makers must now be willing to pay a minimum of $52,953 for an additional participant with a negative drug test at 12 months and $38,696 for an additional employed participant. There is no established threshold value or a comparative study to determine cost-effectiveness for either outcome measure; instead, the authors discussed how to contextualize their ICERs. For negative drug tests, the authors compared the daily cost of ACWS per participant to other substance use disorder treatment costs. This discussion is still relevant as the cost of ACWS was not changed by the corrections. For employment, the authors compared the ICER for an additional participant employed to monthly, full-time, wages at the Federal minimum wage. The authors concluded that ACWS could be considered a good value, given that the cost for an additional employed participant was lower than estimated earnings. However, the corrected ICER of $38,696 far exceeds the monthly, full-time wages at the Federal minimum wage. Instead, the corrected ICER for an additional participant employed should be considered in the context of the societal benefits of increased employment. These benefits encompass reduced welfare payments, decreased criminal activity, an expanded tax base, and heightened productivity. While quantifying and valuing these benefits may present challenges, previous research on the societal cost of crime suggests that reductions in criminal activity can yield significant societal gains (e.g., McCollister et al., 2010). The authors concluded that ACWS may be cost-effective for both drug use and employment but only if a stakeholder places a value higher than their respective ICERs. This conclusion remains unchanged, but the value needed to make ACWS cost-effective is now much higher. Full versions of the revise Table 4, Table 5 and Table 6 and revised CEAC figures are included in Corrected Tables and Figures. Each table includes updated footnotes which explain the correct calculations for the ICERs. Corrected Figs.