A randomized study of cellphone technology to reinforce alcohol abstinence in the natural environment

Abstract

Aims: Contingency management (CM) uses tangible incentives to systematically reinforce abstinence and is among the most efficacious psychosocial substance abuse treatments. This study assessed the feasibility and initial efficacy of a portable CM procedure designed to address technical limitations for detecting drinking that have prevented using CM for alcohol problems.

Design: Participants received a cellphone, breathalyzer and training on video-recording alcohol breath tests (BrACs) and texting results. For 4 weeks, staff texted participants one to three times daily indicating that a breath alcohol concentration test (BrAC) was due within the hour. Participants were randomized to (1) modest compensation for submitting dated time-stamped BrAC videos regardless of results or (2) the same plus CM with escalating vouchers for on-time alcohol-negative tests (n-BrAC; <02 g/dl). 'Thank-you' texts were sent, with CM patients also informed of results-based earnings.

Setting: Participants' natural environment.

Participants: Adults (n = 30; ≥ 21 years) who drank frequently but were not physiologically dependent.

Measurements: Drinking and related problems were assessed at intake and week 4. BrACs and self-reports of drinking were collected throughout. The primary outcome was the percentage of n-BrACs. Other outcomes were the longest duration of consecutive n-BrACs (longest duration of abstinence) and self-reports of drinking.

Findings: On average, 88.6% (10.4%) of BrACs were submitted on time, without group differences (P = 0.18). The percentage of n-BrACs and LDA were greater with CM, and there was an interaction effect on drinking frequency and negative consequences, with decreases over time with CM (P = 0.00; effect sizes d = 0.52-0.62).

Conclusion: Cellphone technology may be useful for extending contingency management to treatment for alcohol problems.

Trial registration: ClinicalTrials.gov NCT01307345.

Figure 1

The flow of participants from the point of initial contact through data analysis is presented per Consolidating Standards of Reporting Trials (i.e., CONSORT) guidelines.

Figure 2

Primary drinking outcomes were the percent of breath tests negative for alcohol (< 0.02 g/sL), LDA (longest duration (in days) of abstinence, defined by negative breath test results), and change in frequency and magnitude of drinking over the 28 days immediately pre-study compared to the 28-day intervention period. Study conditions differed significantly on the percent of breath tests negative for alcohol (< 0.02 g/dL), LDA, and as a function of condition and time on frequency of drinking. Data points represent means and standard deviations. The asterisk (*) indicates a significant difference between groups, p≤ .01. † indicates a significant condition by time interaction, p < .01.