Review quality: High

Review aim: "To assess the effectiveness of early, computerized brief interventions on alcohol and cannabis use by young people aged 15 to 25 years who are high or risky consumers of either one or both of these substances." (Page 16)

Where it fits in the pathway: Prevention and early intervention (Other early intervention and engagement)

(Note: This review contains findings for both alcohol and drug use separately and so it can be found in two points in the online map, and this summary can be found in two sections of this appendix.)

This review examined the findings of 60 studies evaluating a range of early computerised brief interventions, of which 53 focused on alcohol, three focused on cannabis, and four on both alcohol and cannabis. The studies focused on hazardous and/or harmful alcohol and/or cannabis users. Although some included studies were 'screening and brief interventions', most used a brief assessment of consumption, or else conducted screening to identify who to include in the study and so did not evaluate the screening component of a 'screening and brief intervention', whilst others used brief assessments rather than validated screening tools. Therefore, since the review's focus was on the effect of interventions on those already identified as hazardous/harmful alcohol/cannabis users, it fits within 'other early intervention and engagement'. Thirteen analyses were included in this map – see detailed findings.

Overview of findings: "The interventions significantly reduce alcohol consumption in the short-term compared to no intervention, but the effect size is small, and there is no significant effect in the long-term. There are also shortcomings in the quality of the evidence. Interventions which provide an assessment of alcohol use with feedback may have a larger effect than those which do not, but again, the evidence is weak. The few studies on cannabis did not show significant effects in the reduction of cannabis consumption. There was no evidence of adverse effects." (Page 6)

Detailed findings

(Note: We recommend you refer to the review for the specific information about the intervention, comparators, outcomes and measurement timing for each of these findings.)

Findings on alcohol use:

1) Assessment and feedback vs. no intervention for alcohol consumption at short term follow-up: A meta-analysis of 15 interventions found that assessment and feedback significantly reduced short-term alcohol consumption compared to no intervention. The effect size is small. The quality of the evidence was low. (n = 14 studies / 15 interventions; n = 4,558 participants; pooled effect size (SMD) = -0.17; 95% CI = -0.27 to -0.08).

2) Assessment and feedback vs. no intervention for alcohol consumption at longer term follow-up: A For long-term alcohol consumption, there were only three studies. The effect size is of a similar magnitude. The quality of the evidence was low. (n = 3 studies; n = 916 participants; pooled effect size (SMD) = -0.17; 95% CI = -0.30 to -0.04).

3) Assessment and feedback vs. assessment only for alcohol consumption at short term follow-up: A meta-analysis of 24 studies with 25 independent samples showed reduced short-term alcohol consumption from assessment and feedback compared to assessment only. The effect size is small. The quality of the evidence was low.

(n = 22 studies / 25 interventions; n = 5,794 participants; pooled effect size (SMD) = -0.15; 95% CI = -0.25 to -0.06).

4) Assessment and feedback vs. assessment only for alcohol consumption at longer term follow-up: For the long-term follow-up there were only three studies; and there was no significant effect. The quality of the evidence was very low.

(n = 3 studies; n = 638 participants; pooled effect size (SMD) = -0.03; 95% CI = -0.19 to 0.12).

5) Feedback plus moderation skills vs. feedback only for alcohol consumption at short term follow-up: Two studies explored the short-term effect of adding moderation skills training to feedback, and they found a small to moderate effect size; low quality evidence.

(n = 2 studies; n = 302 participants; pooled effect size (SMD) = -0.26, 95% CI -0.49 to 0.03).

6) Assessment and feedback vs. education for alcohol consumption at short term follow-up: A meta-analysis of seven studies showed no significant short-term effect of assessment and feedback compared to education. The quality of the evidence was very low.

(n = 7 studies; n = 1,131 participants; pooled effect size (SMD) = -0.02; 95% CI = -0.21 to 0.17).

7) Comprehensive feedback vs. brief feedback for alcohol consumption at short term follow-up: Four studies directly compared a brief computerised intervention using comprehensive feedback to a computerised brief intervention using brief feedback. Hence, the comprehensive interventions were also brief, but the feedback was a little less brief than in the comparison group. A meta-analysis of four studies did not find an added short-term effect of comprehensive feedback compared to brief feedback. The evidence was of low quality.

(n = 4 studies; n = 839 participants; pooled effect size (SMD) = -0.01; 95% CI = -0.18 to 0.19).

8) Computer assessment and feedback vs. counsellor assessment and feedback for alcohol consumption at short term follow-up: A meta-analysis of six studies did not find that the short-term effect of computerised brief interventions is different from a brief intervention delivered by a counsellor. The evidence was very low quality.

(n = 6 studies; n = 853 participants; pooled effect size (SMD) = -0.10; 95% CI = -0.30 to 0.11).

9) Computer assessment and feedback vs. counsellor assessment and feedback for alcohol consumption at longer term follow-up: The two studies with long-term effects also showed no difference. The evidence was very low quality.

(n = 2 studies; n = 443 participants; pooled effect size (SMD) = -0.10; 95% CI = -0.53 to 0.32).

10) Gender-specific feedback vs. gender-neutral feedback for alcohol consumption at short term follow-up: We found three studies comparing gender-specific feedback with gender-neutral feedback. A meta-analysis of three studies indicate a small, but not statistically significant effect, and the evidence was of low quality.

(n = 3 studies; n = 586 participants; pooled effect size (SMD) = -0.14, 95% CI -0.3 to 0.03).

11) Multi-dose assessment and feedback vs. single dose assessment and feedback for alcohol consumption at short term follow-up: A meta-analysis of four studies by the same first author found a 16 percent significant short-term reduction in drinking after a repeated assessment and feedback compared to a single assessment and feedback. The quality of evidence was moderate.

(n = 4 studies; n = 7,357 participants; pooled effect size (Rate ratio) = 0.84; 95% CI -0.78 to 0.91).

Findings on drug use:

12) Assessment and feedback compared to assessment only for cannabis consumption at short term follow-up: A meta-analysis with three studies did not find any short-term effect of adding feedback to assessment only; low quality evidence.

(n = 3 studies; n = 638 participants; pooled effect size (SMD) = -0.03, 95% CI -0.19 to 0.12).

13) Assessment and feedback vs. education for cannabis consumption at short term follow-up: Two studies compared assessment and feedback to education and found a non-significant small reduction in cannabis consumption. The evidence quality was low.

(n = 2 studies; n = 234 participants; pooled effect size (SMD) = -0.08, 95% CI -0.33 to 0.18).

Review Information

Review focus: Digital drug and alcohol interventions.

Type of analysis: Meta-analysis.

Number of included studies: 60 studies - 59 RCTs and one cluster RCT. 53 studies focused on alcohol, three focused on cannabis, and four focused on both alcohol and cannabis.

Population focus: Young people 15-25 years, who are high or risky consumers of alcohol and/or cannabis.

Country focus: USA (n = 44 studies), New Zealand (n = 4 studies), the Netherlands (n = 2 studies), Sweden (n = 4 studies), Australia (n = 2 studies), Germany (n = 1 studies), Switzerland (n = 1 studies) and Brazil (n = 1 study), multiple European countries (n = 1 study).

Digital intervention description: A range of early, computerised brief interventions. Interventions included any preventive or therapeutic activity administered within an hour or less of the substance abuse.

Comparator(s): A variety of control conditions were used including: no intervention, waitlist control, alternative brief intervention (computerised or face-to-face).

Outcomes: Reviewers grouped outcomes into the following categories 'short term' (< 6 months) and 'long term' (>6 months). The following outcomes were measured:

1) Alcohol consumption: daily drinking questionnaire, the Alcohol Timeline Follow Back (TLFB), urine analysis, blood sample analysis, frequency, quantity or peak consumption, occasions, drinking days.

2) Drug use / Substance-misuse: Cannabis Abuse Screening Test, Revised Drug History Questionnaire, self-report.

3) Adverse outcomes: No details provided.