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Intervenciones escolares breves y resultados conductuales para los adolescentes que consumen drogas

Information

DOI:
https://doi.org/10.1002/14651858.CD008969.pub3Copy DOI
Database:
  1. Cochrane Database of Systematic Reviews
Version published:
  1. 20 January 2016see what's new
Type:
  1. Intervention
Stage:
  1. Review
Cochrane Editorial Group:
  1. Cochrane Drugs and Alcohol Group

Copyright:
  1. Copyright © 2016 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.

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Authors

  • Tara Carney

    Correspondence to: Alcohol, Tobacco and Other Drug Research Unit, South African Medical Research Council, Cape Town, South Africa

    [email protected]

  • Bronwyn J Myers

    Alcohol Tobacco and Other Drug Research Unit, South African Medical Research Council, Cape Town, South Africa

    Department of Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa

  • Johann Louw

    Department of Psychology, University of Cape Town, Cape Town, South Africa

  • Charles I Okwundu

    Centre for Evidence‐based Health Care, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa

    South African Cochrane Centre, South African Medical Research Council, Tygerberg, South Africa

Contributions of authors

Tara Carney developed the data extraction form, was responsible for conducting the meta‐analysis and overseeing the drafting of the review, and is the contact review author. Tara Carney and Bronwyn Myers read all titles and abstracts that resulted from the search process and selected possibly relevant studies, and then Tara Carney obtained full copies of these studies, which both of these review authors used to undertake data extraction. Bronwyn Myers participated in the writing of the review and gave critical feedback on the drafts of the reviews. Johann Louw was available to assist in any of these decisions if necessary, participated in the design and writing of the review, and gave critical feedback on the drafts of the reviews. Charles Okwundu assisted with the meta‐analysis of the extracted data as well as the Results and Discussion sections. All review authors reviewed and commented on the drafts and final version of the review.

Sources of support

Internal sources

  • South African Medical Research Council, South Africa.

External sources

  • Open Society Foundation for South Africa, South Africa.

    Grant received

Declarations of interest

Tara Carney: None known.
Bronwyn Myers: None known.
Johann Louw: None known.
Charles Okwundu: None known.

Acknowledgements

The review authors would like to thank Elizabeth Pienaar and Joy Oliver of the South African Cochrane Centre (Cape Town, South Africa) and Zuzana Mitrova of the Cochrane Drugs and Alcohol Review Group (Rome, Italy) for their assistance with search strategies and other support for this review.

Version history

Published

Title

Stage

Authors

Version

2016 Jan 20

Brief school‐based interventions and behavioural outcomes for substance‐using adolescents

Review

Tara Carney, Bronwyn J Myers, Johann Louw, Charles I Okwundu

https://doi.org/10.1002/14651858.CD008969.pub3

2014 Feb 04

Brief school‐based interventions and behavioural outcomes for substance‐using adolescents

Review

Tara Carney, Bronwyn J Myers, Johann Louw, Charles I Okwundu

https://doi.org/10.1002/14651858.CD008969.pub2

2011 Feb 16

Brief school‐based interventions and behavioural outcomes for substance‐using adolescents

Protocol

Tara Carney, Bronwyn J Myers, Johann Louw

https://doi.org/10.1002/14651858.CD008969

Differences between protocol and review

We made the following changes to the present update from the previous version.

  1. We removed the tobacco frequency outcomes, as this was not listed in the protocol and does not fall under the Cochrane Drugs and Alcohol Review Group.

  2. We included an additional article (Winters 2012), which allowed for the analysis of outcomes by follow‐up period.

  3. We changed 'Summary of findings' tables and GRADE quality of evidence accordingly.

  4. We assessed risk of performance bias.

Keywords

MeSH

PICOs

Population
Intervention
Comparison
Outcome

The PICO model is widely used and taught in evidence-based health care as a strategy for formulating questions and search strategies and for characterizing clinical studies or meta-analyses. PICO stands for four different potential components of a clinical question: Patient, Population or Problem; Intervention; Comparison; Outcome.

See more on using PICO in the Cochrane Handbook.

Study flow diagram Carney 2014.
Figures and Tables -
Figure 1

Study flow diagram Carney 2014.

Study flow diagram for updated review.
Figures and Tables -
Figure 2

Study flow diagram for updated review.

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
Figures and Tables -
Figure 3

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
Figures and Tables -
Figure 4

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.

Comparison 1 Brief intervention versus information provision, Outcome 1 Alcohol Frequency: number of alcohol days past 30 days.
Figures and Tables -
Analysis 1.1

Comparison 1 Brief intervention versus information provision, Outcome 1 Alcohol Frequency: number of alcohol days past 30 days.

Comparison 1 Brief intervention versus information provision, Outcome 2 Alcohol Quantity: number of standard drinks in past 30 days.
Figures and Tables -
Analysis 1.2

Comparison 1 Brief intervention versus information provision, Outcome 2 Alcohol Quantity: number of standard drinks in past 30 days.

Comparison 1 Brief intervention versus information provision, Outcome 3 Cannabis Quantity: number of joints smoked in past 30 days.
Figures and Tables -
Analysis 1.3

Comparison 1 Brief intervention versus information provision, Outcome 3 Cannabis Quantity: number of joints smoked in past 30 days.

Comparison 1 Brief intervention versus information provision, Outcome 4 Cannabis Mean Dependence Score.
Figures and Tables -
Analysis 1.4

Comparison 1 Brief intervention versus information provision, Outcome 4 Cannabis Mean Dependence Score.

Comparison 1 Brief intervention versus information provision, Outcome 5 Cannabis frequency: number of days smoked cannabis in past 30 days.
Figures and Tables -
Analysis 1.5

Comparison 1 Brief intervention versus information provision, Outcome 5 Cannabis frequency: number of days smoked cannabis in past 30 days.

Comparison 1 Brief intervention versus information provision, Outcome 6 Secondary outcomes related to substance use: Mean Problem Score.
Figures and Tables -
Analysis 1.6

Comparison 1 Brief intervention versus information provision, Outcome 6 Secondary outcomes related to substance use: Mean Problem Score.

Comparison 2 Brief intervention versus assessment only, Outcome 1 Alcohol Frequency: number of alcohol days.
Figures and Tables -
Analysis 2.1

Comparison 2 Brief intervention versus assessment only, Outcome 1 Alcohol Frequency: number of alcohol days.

Comparison 2 Brief intervention versus assessment only, Outcome 2 Alcohol Quantity: number of standard drinks.
Figures and Tables -
Analysis 2.2

Comparison 2 Brief intervention versus assessment only, Outcome 2 Alcohol Quantity: number of standard drinks.

Comparison 2 Brief intervention versus assessment only, Outcome 3 Alcohol Abuse: number of symptoms.
Figures and Tables -
Analysis 2.3

Comparison 2 Brief intervention versus assessment only, Outcome 3 Alcohol Abuse: number of symptoms.

Comparison 2 Brief intervention versus assessment only, Outcome 4 Alcohol Dependence: number of symptoms.
Figures and Tables -
Analysis 2.4

Comparison 2 Brief intervention versus assessment only, Outcome 4 Alcohol Dependence: number of symptoms.

Comparison 2 Brief intervention versus assessment only, Outcome 5 Cannabis frequency: number of cannabis use days.
Figures and Tables -
Analysis 2.5

Comparison 2 Brief intervention versus assessment only, Outcome 5 Cannabis frequency: number of cannabis use days.

Comparison 2 Brief intervention versus assessment only, Outcome 6 Cannabis Abuse: number of symptoms.
Figures and Tables -
Analysis 2.6

Comparison 2 Brief intervention versus assessment only, Outcome 6 Cannabis Abuse: number of symptoms.

Comparison 2 Brief intervention versus assessment only, Outcome 7 Cannabis Dependence: number of symptoms.
Figures and Tables -
Analysis 2.7

Comparison 2 Brief intervention versus assessment only, Outcome 7 Cannabis Dependence: number of symptoms.

Comparison 2 Brief intervention versus assessment only, Outcome 8 Secondary outcomes related to substance use: Mean score on personal consequences scale.
Figures and Tables -
Analysis 2.8

Comparison 2 Brief intervention versus assessment only, Outcome 8 Secondary outcomes related to substance use: Mean score on personal consequences scale.

Summary of findings for the main comparison. Brief intervention compared to information provision for substance‐using adolescents

Brief intervention compared to information provision for substance‐using adolescents

Patient or population: Substance‐using adolescents
Settings: High schools or further education training colleges
Intervention: Brief intervention
Comparison: Information provision

Outcomes

Illustrative comparative risks* (95% CI)

Estimate effect
(95% CI)

No of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

Information provision

Brief intervention

Alcohol frequency
Self report questionnaires
Medium‐term follow‐up: 4 to 6 months

See comment

The standardised mean alcohol frequency in the intervention groups was 0.01 standard deviations lower
(0.20 lower to 0.18 higher)

SMD ‐0.01 (‐0.20 to 0.18)

434
(2 studies)

⊕⊕⊕⊝
moderate1

Number of days of alcohol use

Alcohol quantity
Self report questionnaires

Medium‐term follow‐up: 4 to 6 months

See comment

The standardised mean alcohol quantity in the intervention groups was 0.14 standard deviations lower
(0.33 lower to 0.05 higher)

SMD ‐0.14 (‐0.33 to 0.05)

434
(2 studies)

⊕⊕⊕⊝
moderate1

Number of standard alcohol units

Cannabis dependence
Self report questionnaires
Short‐term follow‐up: 1 to 3 months

See comment

The standardised mean cannabis dependence score in the intervention groups was 0.09 standard deviations lower

(0.27 lower to 0.09 higher)

SMD ‐0.09 (‐0.27 to 0.09)

470
(2 studies)

⊕⊕⊕⊝
moderate1

Mean dependence score

Cannabis frequency
Self report questionnaires
Short‐term follow‐up: 1 to 3 months

See comment

The mean cannabis frequency in the intervention groups was
0.07 standard deviations lower
(0.25 lower to 0.11 higher)

SMD ‐0.07 (‐0.25 to 0.11)

470
(2 studies)

⊕⊕⊕⊝
moderate1

Number of days cannabis use

Secondary outcomes related to substance use
Self report questionnaires

Short‐term follow‐up: 1 to 3 months

See comment

The mean behavioural outcomes related to substance use in the intervention groups was
‐0.01 standard deviations lower
(0.19 lower to 0.17 higher)

SMD ‐0.01 (‐0.19 to 0.17)

470
(2 studies)

⊕⊕⊕⊝
moderate1

Interactional Problems Score

*The basis for the assumed risk (e.g. the mean control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the estimate effect of the intervention (and its 95% CI). The estimate effects for certain outcomes were not estimable due to only one study assessing the specific outcome, or extremely high levels of heterogeneity making effects across studies difficult to compare.
CI: confidence interval; SMD: standardised mean difference

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1Risk of bias (‐1): It was not possible to blind the participants in all of the included studies. There was also uncertainty in two of the studies about allocation concealment and blinding of outcome assessor (Walker 2011; Werch 2005).

Figures and Tables -
Summary of findings for the main comparison. Brief intervention compared to information provision for substance‐using adolescents
Summary of findings 2. Brief intervention compared to assessment only for substance‐using adolescents

Brief intervention compared to assessment only for substance‐using adolescents

Patient or population: Substance‐using adolescents
Settings: High schools or further education colleges
Intervention: Brief intervention
Comparison: Assessment only

Outcomes

Illustrative comparative risks* (95% CI)

Estimate effect
(95% CI)

No of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

Assessment only

Brief intervention

Alcohol frequency

Self report questionnaires
Medium‐term follow‐up: 4 to 6 months

See comment

The standardised mean alcohol frequency in the intervention groups was 0.91 standard deviations lower
(1.21 lower to 0.61 lower)

SMD ‐0.91 (‐1.21 to ‐0.61)

242
(2 studies)

⊕⊕⊝⊝
low1, 2

Number of days of alcohol use

Alcohol quantity
Self report questionnaires

Medium‐term follow‐up: 4 to 6 months

See comment

The standardised mean alcohol quantity in the intervention groups was 0.16 standard deviations lower
(0.45 lower to 0.14 higher)

SMD ‐0.16

(‐0.45 to 0.14)

179

(1 study)

⊕⊕⊝⊝
low1,2

Number of standard alcohol units

Cannabis dependence
Self report questionnaires
Medium‐term follow‐up: 4 to 6 months

See comment

The mean cannabis dependence in the intervention groups was
0.56 standard deviations lower
(0.57 lower to 0.06 higher)

SMD ‐0.26 (‐0.57 to 0.36)

190
(1 study)

⊕⊕⊝⊝
low1, 2

Mean dependence score

Cannabis frequency
Self report questionnaires
Long‐term follow‐up: 7 to 12 months

See comment

The mean cannabis frequency in the intervention groups was
0.54 standard deviations lower
(0.77 lower to 0.31 higher)

SMD ‐0.54 (‐0.77 to ‐0.31)

338
(2 studies)

⊕⊕⊝⊝
low1,2

Number of days of cannabis use

Secondary outcomes related to substance use

Self report questionnaires

Medium‐term follow‐up: 4 to 6 months

See comment

The mean mean behavioural outcomes related to substance use in the intervention groups was
0.65 standard deviations lower
(1.58 lower to 0.28 higher)

SMD ‐0.65 (‐1.58 to 0.28)

242
(2 studies)

⊕⊕⊝⊝
low1, 2

Interactional Problems Score

*The basis for the assumed risk (e.g. the mean control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the estimate effect of the intervention (and its 95% CI). The estimate effects for certain outcomes were not estimable due to only one study assessing the specific outcome, or extremely high levels of heterogeneity making effects across studies difficult to compare.
CI: confidence interval; SMD: standardised mean difference

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1Risk of bias (‐1): It was not possible to blind the participants in all of the included studies. There was no allocation concealment in two of the included studies, and it was unclear whether the outcome assessor was blinded (Winters 2007b; Winters 2012). The other study was also not free of selective reporting bias (McCambridge 2004).
2Imprecision (‐1): The confidence intervals contained the null value of zero and the upper or lower confidence limit crosses an effect size of 0.5 in either direction; the sample size was also small for medium‐term follow‐up.

Figures and Tables -
Summary of findings 2. Brief intervention compared to assessment only for substance‐using adolescents
Comparison 1. Brief intervention versus information provision

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Alcohol Frequency: number of alcohol days past 30 days Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

1.1 Short‐term Follow up (1‐3 months)

1

269

Std. Mean Difference (IV, Random, 95% CI)

‐0.05 [‐0.29, 0.19]

1.2 Medium‐term Follow up (4‐6 months)

2

434

Std. Mean Difference (IV, Random, 95% CI)

‐0.01 [‐0.20, 0.18]

2 Alcohol Quantity: number of standard drinks in past 30 days Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

2.1 Short‐term Follow up (1‐3 months)

1

269

Std. Mean Difference (IV, Random, 95% CI)

0.02 [‐0.22, 0.26]

2.2 Medium‐term Follow up (4‐6 months)

2

434

Std. Mean Difference (IV, Random, 95% CI)

‐0.14 [‐0.33, 0.05]

3 Cannabis Quantity: number of joints smoked in past 30 days Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

3.1 Short‐term Follow up (1‐3 months)

1

269

Std. Mean Difference (IV, Random, 95% CI)

0.0 [‐0.24, 0.24]

3.2 Medium‐term Follow up (4‐6 months)

1

264

Std. Mean Difference (IV, Random, 95% CI)

‐0.15 [‐0.39, 0.09]

4 Cannabis Mean Dependence Score Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

4.1 Short‐term Follow up (1‐3 months)

2

470

Std. Mean Difference (IV, Random, 95% CI)

‐0.09 [‐0.27, 0.09]

4.2 Medium‐term Follow up (4‐6 months)

1

264

Std. Mean Difference (IV, Random, 95% CI)

0.06 [‐0.18, 0.30]

4.3 Long‐term Follow up (7‐12 months)

1

186

Std. Mean Difference (IV, Random, 95% CI)

‐0.09 [‐0.38, 0.20]

5 Cannabis frequency: number of days smoked cannabis in past 30 days Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

5.1 Short‐term Follow up (1‐3 months)

2

470

Std. Mean Difference (IV, Random, 95% CI)

‐0.07 [‐0.25, 0.11]

5.2 Medium‐term Follow up (4‐6 months)

1

264

Std. Mean Difference (IV, Random, 95% CI)

‐0.06 [‐0.30, 0.18]

5.3 Long‐term Follow up (7‐12 months)

1

186

Std. Mean Difference (IV, Random, 95% CI)

‐0.02 [‐0.31, 0.26]

6 Secondary outcomes related to substance use: Mean Problem Score Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

6.1 Short‐term Follow up (1‐3 months)

2

470

Std. Mean Difference (IV, Random, 95% CI)

‐0.01 [‐0.19, 0.17]

6.2 Medium‐term Follow up (4‐6 months)

1

264

Std. Mean Difference (IV, Random, 95% CI)

‐0.13 [‐0.37, 0.11]

6.3 Long‐term Follow up (7‐12 months)

1

186

Std. Mean Difference (IV, Random, 95% CI)

‐0.10 [‐0.39, 0.19]

Figures and Tables -
Comparison 1. Brief intervention versus information provision
Comparison 2. Brief intervention versus assessment only

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Alcohol Frequency: number of alcohol days Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

1.1 Medium‐term Follow up (4‐6 months)

2

242

Std. Mean Difference (IV, Random, 95% CI)

‐0.91 [‐1.21, ‐0.61]

1.2 Long‐term Follow up (7‐12 months)

1

170

Std. Mean Difference (IV, Random, 95% CI)

‐0.20 [‐0.53, 0.14]

2 Alcohol Quantity: number of standard drinks Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

2.1 Medium‐term Follow up (4‐6 months)

1

179

Std. Mean Difference (IV, Random, 95% CI)

‐0.16 [‐0.45, 0.14]

2.2 Long‐term Follow up (7‐12 months)

1

162

Std. Mean Difference (IV, Random, 95% CI)

‐0.16 [‐0.47, 0.15]

3 Alcohol Abuse: number of symptoms Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

3.1 Medium‐term Follow up (4‐6 months)

1

190

Std. Mean Difference (IV, Random, 95% CI)

‐0.38 [‐0.70, ‐0.07]

3.2 Long‐term Follow up (7‐12 months)

1

170

Std. Mean Difference (IV, Random, 95% CI)

‐0.72 [‐1.07, ‐0.38]

4 Alcohol Dependence: number of symptoms Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

4.1 Medium‐term Follow Up (4‐6 months)

1

190

Std. Mean Difference (IV, Random, 95% CI)

‐0.58 [‐0.90, ‐0.26]

4.2 Long‐term Follow up (7‐12 months)

1

170

Std. Mean Difference (IV, Random, 95% CI)

‐0.13 [‐0.47, 0.20]

5 Cannabis frequency: number of cannabis use days Show forest plot

3

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

5.1 Short‐term Follow up (1‐3 months)

1

179

Std. Mean Difference (IV, Random, 95% CI)

‐0.83 [‐1.14, ‐0.53]

5.2 Medium‐term Follow up (4‐6 months)

2

242

Std. Mean Difference (IV, Random, 95% CI)

‐0.23 [‐0.50, 0.05]

5.3 Long‐term Follow up (7‐12 months)

2

338

Std. Mean Difference (IV, Random, 95% CI)

‐0.54 [‐0.77, ‐0.31]

6 Cannabis Abuse: number of symptoms Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

6.1 Medium‐term Follow up (4‐6 months)

1

190

Std. Mean Difference (IV, Random, 95% CI)

‐0.34 [‐0.65, ‐0.02]

6.2 Long‐term Follow up (7‐12 months)

1

170

Std. Mean Difference (IV, Random, 95% CI)

‐0.62 [‐0.96, ‐0.28]

7 Cannabis Dependence: number of symptoms Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

7.1 Medium‐term Follow up (4‐6 months)

1

190

Std. Mean Difference (IV, Random, 95% CI)

‐0.26 [‐0.57, 0.06]

7.2 Long‐term Follow up (7‐12 months)

1

170

Std. Mean Difference (IV, Random, 95% CI)

‐0.97 [‐1.32, ‐0.62]

8 Secondary outcomes related to substance use: Mean score on personal consequences scale Show forest plot

2

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

8.1 Medium‐term Follow up (4‐6 months)

2

242

Std. Mean Difference (IV, Random, 95% CI)

‐0.65 [‐1.58, 0.28]

8.2 Long‐term Follow up (7‐12 months)

1

170

Std. Mean Difference (IV, Random, 95% CI)

‐0.78 [‐1.13, ‐0.44]

Figures and Tables -
Comparison 2. Brief intervention versus assessment only