Jay 1984.

Methods	Single site, parallel group RCT Location: Children and Youth Project site in Augusta, GA, USA Time frame: no mention Sample size estimation and outcome of focus: no mention
Participants	General with N: 57 adolescents randomized (participants were 14 to 19 years old) Inclusion criteria: attending adolescent gynaecology clinic and willing to use oral contraceptives (OCs) Exclusion criteria: no mention
Interventions	Study focus: increasing OC adherence Intervention: peer counselors trained (with role playing) on conversational and interaction skills; observational skills; decision‐making; formal counseling; confidentiality; problem‐solving; birth control. Comparison: Nurse counselors with same training as peer counselors. Both groups had 3 appointments.
Outcomes	Primary: OC non‐adherence via Guttman scale; avoidance of pregnancy (apparently self‐report); appointment adherence; pill count; urinary fluorescence for riboflavin (marker added to OCs). Secondary: attrition rate at 4 months (end of study), i.e. failed to keep second rescheduled appointment or discontinued OC regimen. Follow‐up: 4 months
Notes	31 (54%) subjects were assigned to the nurse‐counselor group, and 26 (46%) were assigned to the peer‐counselor group. 50% (28 or 29) of the participants were expected to be assigned to each group. A sampling error of this degree was not significant with a sample size of 57. Trial registration: no details Funding: funded in part by a grant from the Georgia Department of Human Services Declarations of interest: no details provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated random numbers table
Allocation concealment (selection bias)	Unclear risk	No information
Blinding of participants and personnel (performance bias) All outcomes	High risk	No details provided of blinding of participants or providers; not feasible due to type of intervention
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Urine samples for fluorescence: 3 independent observers evaluated in double‐blind fashion No details provided of blinding of self‐reported pregnancy and pill count for non‐adherence scale
Incomplete outcome data (attrition bias) All outcomes	High risk	Losses to follow‐up: 33% overall; nurse‐counseled, 42%; peer‐counseled, 23%
Selective reporting (reporting bias)	Unclear risk	No protocol was available, however the outcomes of compliance/non‐compliance prespecified in the manuscript were reported.
Other bias	Low risk	Appeared free of other sources of bias