School-based prevention for illicit drugs' use

Background Drug addiction is a chronic, relapsing disease. Primary interventions should be aimed to reduce first use, or prevent the transition from experimental use to addiction. School is the appropriate setting for preventive interventions. Objectives To evaluate the effectiveness of school‐based interventions in improving knowledge, developing skills, promoting change, and preventing or reducing drug use versus usual curricular activities or a different school‐based intervention . Search methods We searched the Cochrane Drug and Alcohol Group trial register (February 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2004), MEDLINE (1966 to February 2004) , EMBASE (1988 to February 2004), and other databases. We also contacted researchers in the field and checked reference lists of articles. Selection criteria Randomised controlled trials (RCT), case controlled trials (CCT) or controlled prospective studies (CPS) evaluating school‐based interventions designed to prevent substance use. Data collection and analysis Two authors independently extracted data and assessed trial quality. Main results 32 studies (29 RCTs and three CPSs) were included with 46539 participants. Twenty eight were conducted in the USA; most were focused on 6th‐7th grade students, and based on post‐test assessment. RCTs (1) Knowledge versus usual curricula Knowledge focused programs improve drug knowledge (standardised mean difference (SMD) 0.91; 95% confidence interval (CI) 0.42 to 1.39). (2) Skills versus usual curricula Skills based interventions increase drug knowledge (weighted mean difference (WMD) 2.60; 95% CI 1.17 to 4.03), decision making skills (SMD 0.78; CI 95%: 0.46 to 1.09), self‐esteem (SMD 0.22; CI 95% 0.03 to 0.40), peer pressure resistance (relative risk (RR) 2.05; CI 95%: 1.24 to 3.42), drug use (RR 0.81; CI 95% 0.64 to 1.02), marijuana use (RR 0.82; CI 95% 0.73 to 0.92) and hard drug use (RR 0.45; CI 95% 0.24 to 0.85). (3) Skills versus knowledge No differences are evident. (4) Skills versus affective Skills‐based interventions are only better than affective ones in self‐efficacy (WMD 1.90; CI 95%: 0.25 to 3.55). Results from CPSs No statistically significant results emerge from CPSs. Authors' conclusions Skills based programs appear to be effective in deterring early‐stage drug use. The replication of results with well designed, long term randomised trials, and the evaluation of single components of intervention (peer, parents, booster sessions) are the priorities for research. All new studies should control for cluster effect.