Calderon 2008.

Methods	Stratified RCT. Women were stratified by risk factor combination (1 of 15 possible combinations of 4 risk behaviours (IPV, alcohol, drugs, smoking)).
Participants	Women attending 5 prenatal clinics in the San Francisco bay area (USA). Only women with risk factors were randomised. 37 women experiencing DV were randomised. Inclusion criteria: women less than 26 weeks’ gestation, English speaking, aged 18 years or older, not attending for first prenatal visit who screened positive for one (or more than one) of 4 risk factors (smoking, alcohol, drug use or DV). Exclusion criteria: women who had no risk factors were not randomised.
Interventions	Experimental intervention: video doctor‐assessment with appropriate messages for risk factor (e.g. encouraging women to discuss problem) and healthcare staff were alerted and given a cueing sheet to discuss risk factor (DV). (20 women randomised to the intervention group.) Control/Comparison intervention: all women had video doctor‐assessment but healthcare staff did not receive cueing sheet. Women randomised to the control group received usual care and any discussion of risk was at the discretion of healthcare staff.  (17 women randomised to control condition.)
Outcomes	This study examined whether discussions re DV occurred and women’s views of the discussion (acceptability and helpfulness). No other outcome data were reported.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Sequence generation was by a computer programme, however, it was not clear how stratification affected the randomisation process as some women may have had several risk factors (it was not clear whether these women would then receive several intervention messages and several staff cueing forms).
Allocation concealment (selection bias)	Low risk	By computer programme.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	37 women experiencing DV were randomised and data appear available for all women at the immediate post‐intervention assessment. There were some missing data at follow‐up (32 were followed up at 2 months) but all women were included in a sensitivity analysis (those lost to follow‐up were assumed to have had no discussion of DV).
Selective reporting (reporting bias)	Unclear risk	Results for women assessed with a single risk factor were reported but it seems that women may have had multiple risk factors and multiple interventions and there may have been some interaction effect (it is possible that if a woman had multiple risk factors then she was more likely than those with a single risk factor to have discussions with healthcare staff).
Other bias	Low risk	Other bias not apparent.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Staff would have been aware of group assignment because the interview would have been conducted according to the intervention cue sheet for the intervention group. It is unclear whether women would have been aware of group assignment.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Staff would have been aware of group assignment because the interview would have been conducted according to the intervention cue sheet for the intervention group. It is unclear whether women would have been aware of group assignment. Outcomes are self‐reported, so it is unclear whether these would have been shaped by knowledge of group assignment.