Netherlands 1989.

Methods	Coded packages containing trial drug allocated according to a randomisation list.
Participants	10 primigravid women with chronic hypertension and a positive angiotensin II sensitivity test at 26 weeks' gestation. No proteinuria, BP < 90 mmHg diastolic, serum creatinine < 70 umol/L and an adequately grown fetus.
Interventions	Exp: aspirin 60 mg. Control: placebo.
Outcomes	Women: GH (rise in DBP of 20 mmHg or more); PE (hypertension as before plus proteinuria >/= 500 mg/L); caesarean section. Babies: birthweight < 10th centile.
Notes	All women had methyl dopa.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomisation list
Allocation concealment (selection bias)	Unclear risk	Coded packs of tablets, no further information available.
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: "placebo‐controlled double‐blind"
Incomplete outcome data (attrition bias) All outcomes	Low risk	It appears that all 10 patients were successfully followed up.
Selective reporting (reporting bias)	Low risk	Protocol not available, however it appears that all expected outcomes were reported.
Other bias	Unclear risk	Information on baseline characteristics not presented and compared for all participants. Small sample size.