Simply texting parents about school performance cut teen alcohol and marijuana use nearly in half

An RCT found that sending parents weekly texts about their child's grades and behavior reduced teen lifetime alcohol or marijuana use from 18.2% to 10.2% by the end of 8th grade, at a cost of just $15 per student per year.

Bergman, Peter et al.·American journal of public health·2019·Strong EvidenceRandomized Controlled Trial
RTHC-01940Randomized Controlled TrialStrong Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Randomized Controlled Trial
Evidence
Strong Evidence
Sample
N=318

What This Study Found

By the end of 8th grade, lifetime use of alcohol or marijuana was 18.2% in the control group versus 10.2% in the intervention group (p=.02). The intervention consisted only of sending parents weekly text messages, phone calls, or emails about missed assignments, grades, and behavior. Parenting self-efficacy and student grades were similar between groups.

Key Numbers

318 students enrolled. Lifetime alcohol/marijuana use: 10.2% intervention vs 18.2% control (p=.02). 81% Latino. 50% household income <$15,000. Cost: $15/student/year, automatable to near-zero marginal cost.

How They Did This

Randomized controlled trial in Los Angeles enrolling 318 7th graders and their parents in 2014, with follow-up through 2016. Half had household income under $15,000; 81% were Latino. Intervention: weekly parent communications about academic performance and behavior.

Why This Research Matters

This is a remarkably simple and cheap intervention that achieved meaningful substance use reduction without directly targeting substance use at all. By keeping parents informed about school performance, the intervention apparently enhanced natural parental monitoring.

The Bigger Picture

Most substance use prevention programs target teens directly and have modest effects. This study suggests that simply closing the information gap between schools and parents may be one of the most cost-effective prevention strategies available.

What This Study Doesn't Tell Us

Self-reported substance use may be underestimated. Predominantly Latino, low-income sample may not generalize. The mechanism is unclear since parenting self-efficacy and grades did not differ. Relatively short follow-up (grades 7-8).

Questions This Raises

  • ?Does the effect persist into high school?
  • ?What is the mechanism if parenting self-efficacy did not change?
  • ?Would this work in higher-income or different demographic populations?
  • ?Does the effect extend to other substances?

Trust & Context

Key Stat:
10.2% vs 18.2% use rate
Evidence Grade:
Rated strong because this is a registered randomized controlled trial with objective outcome measurement and a clear effect.
Study Age:
Published in 2019 with 2014-2016 data. Registered at ClinicalTrials.gov (NCT02129153).
Original Title:
Engaging Parents to Prevent Adolescent Substance Use: A Randomized Controlled Trial.
Published In:
American journal of public health, 109(10), 1455-1461 (2019)
Database ID:
RTHC-01940

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled TrialGold standard for testing treatments
This study
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Participants are randomly assigned to treatment or placebo groups to test cause and effect.

What do these levels mean? →

Frequently Asked Questions

How did texting parents reduce teen drug use?

Parents received weekly messages about missed assignments, grades, and behavior. This apparently enhanced parental awareness and monitoring, though the exact mechanism is unclear since self-reported parenting measures did not change.

How much did it cost?

Just $15 per student per year, and the authors note it could be automated to reduce the marginal cost to near zero.

Did it only work for marijuana?

The study measured combined alcohol and marijuana use. The overall initiation rate was cut nearly in half, from 18.2% to 10.2%.

Read More on RethinkTHC

Cite This Study

RTHC-01940·https://rethinkthc.com/research/RTHC-01940

APA

Bergman, Peter; Dudovitz, Rebecca N; Dosanjh, Kulwant K; Wong, Mitchell D. (2019). Engaging Parents to Prevent Adolescent Substance Use: A Randomized Controlled Trial.. American journal of public health, 109(10), 1455-1461. https://doi.org/10.2105/AJPH.2019.305240

MLA

Bergman, Peter, et al. "Engaging Parents to Prevent Adolescent Substance Use: A Randomized Controlled Trial.." American journal of public health, 2019. https://doi.org/10.2105/AJPH.2019.305240

RethinkTHC

RethinkTHC Research Database. "Engaging Parents to Prevent Adolescent Substance Use: A Rand..." RTHC-01940. Retrieved from https://rethinkthc.com/research/bergman-2019-engaging-parents-to-prevent

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.