Ireland 1991.

Methods	Allocation concealment: cards with 'test' or 'control' sealed in envelopes, shuffled and then numbered in sequence. Consecutive envelopes opened.Two arms
Participants	36 women < 38 weeks' gestation with BP >/= 140/90 mmHg on 2 separate days, without proteinuria. Excluded: if lived too far from the hospital to attend for frequent examinations.
Interventions	Exp: choice between oral atenolol 50 mg/day to 100 mg/day and oral methyldopa 750 mg/day to 2250 mg/day. If monotherapy inadequate, 2 drugs combined. Oral bendrofluazide 2.5 mg to 5.0 mg added as a third agent when necessary. (17 women) Control: no antihypertensive. (19 women)
Outcomes	Women: MAP, proteinuria. Babies: perinatal death, Apgar, gestation age at delivery, birthweight, birthweight < 50th centile.
Notes	Korotkoff phase V used for DBP. Additional data provided by authors. Funding: no information about funding source. Declaration of interests not described.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote: "...shuffled into random order..."
Allocation concealment (selection bias)	Low risk	Sealed, identical numbered envelopes.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Open‐label trial.
Blinding of outcome assessment (detection bias) All outcomes	High risk	No.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No.
Selective reporting (reporting bias)	Unclear risk	Assessment from published study report.
Other bias	Unclear risk	Groups appear comparable at baseline. No information about funding source. Declaration of interests not described.