Taylor 2014.

Methods	Design: cluster randomized trial; 16 high schools (urban and rural) allocated to conditions Location: KwaZulu‐Natal, South Africa Time frame: 2009 Sample size estimation and outcome of focus: no information
Participants	General with N: 16 high schools; 816 students Inclusion criteria: 2 of 11 districts (1 urban and 1 rural); 16 of 1580 high schools on Department of Education list; randomly selected grade 8 classes (1st year high school) Exclusion criteria: no information
Interventions	Study focus: teenage pregnancy prevention Theory or model: I‐Change model from 2005 (DeVries 2013); integration of ideas from Theory of Planned Behavior, Social Cognitive Theory, Transtheoretical Model, Health Belief Model, and goal setting theories Intervention: interactive program with 12 weekly sessions addressing choice, body development, contraception (role play included visiting clinic for contraception), parenthood; compulsory program (below) Control: compulsory Lifeskills program + media messages regarding teen pregnancy; had experimental program at trial end
Outcomes	Primary: been pregnant or caused pregnancy; condom use (any); condom use consistency as 4‐point scale from 1 (never) to 4 (always) Secondary: attitudes to teen pregnancy (pro and con scales); intent to prevent pregnancy and to use condoms Follow‐up: 4 months postprogram (8 months after baseline)
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No specifics on sequence generation: 16 of 1580 schools selected; geographical stratification; randomly allocated schools to groups
Allocation concealment (selection bias)	Unclear risk	Students invited from 1 randomly selected grade 8 class
Blinding of participants and personnel (performance bias) All outcomes	High risk	Presume no blinding of participants or providers; not feasible due to type of intervention
Blinding of outcome assessment (detection bias)	Unclear risk	No mention
Outcome measures	High risk	Contraceptive use and pregnancy by self‐report
Incomplete outcome data (attrition bias) All outcomes	High risk	Loss to follow‐up: intervention 11% (48/431); control 23% (89/385); differential losses
Other bias	High risk	Analysis for cluster randomized trial: multivariate linear and logistic regression models included covariates of age, gender, socioeconomic status, sexual experience, and baseline scores. Analysis of behavioral outcomes based on who had sex (could be affected by intervention), rather than all randomized (high risk)