Obtaining preference scores for an abbreviated self-completion version of the Teen-Addiction Severity Index (ASC T-ASI) to value therapy outcomes of systemic family interventions: a discrete choice experiment

Abstract

Background

Systemic family interventions for adolescents with problems of substance use and/or delinquency are increasingly focused subject of economic evaluations. Treatment effects go beyond improvements in commonly measured health-related quality of life (HRQOL). The Teen-Addiction Severity Index (T-ASI) was identified as capable of capturing these broad outcomes. However, it lacks preference-based scores. An abbreviated self-completion version (ASC T-ASI) was created and validated, covering the T-ASI domains substance use, school, work, family, social relationships, justice, and mental health. This study aimed to obtain societal preference scores for the ASC T-ASI.

Methods

Preferences were elicited in a sample of the Dutch general adult population ( n = 1500), using a web-based Discrete Choice Experiment. Choice tasks included two unlabeled alternatives with attributes and levels corresponding to the domains and levels of the ASC T-ASI. A pilot study ( n = 106) informed priors, optimal presentation, and number of choice tasks applied in the main study. Data were analyzed using a mixed multinomial logit model.

Results

Preference scores were logically ordered, with lower scores for worse ASC T-ASI states. Scores were most influenced by reductions in problems concerning the domains substance use, mental health, justice, and family. Tariffs were calculated for each ASC T-ASI state, ranging from 0 (worst situation) to 1 (best situation).

Conclusions

The tariffs enable preference-based assessments of the broad effects of systemic family interventions for adolescents with problems of substance use and/or delinquency. The outcome reflects addiction-related rather than health-related utility and can be used next to generic HRQOL instruments in relevant economic evaluations. Given the source used for the preferences, interpretations and valuation of scores require attention.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10198-023-01633-3.