Algeria 2011.

Methods	Randomised controlled trial.
Participants	164 primiparous women consulting before the 10th week of amenorrhoea without previous vasculo‐renal pathology. Excluded: counter‐indication to use of aspirin, chronic arterial hypertension before pregnancy, chronic nephropathy, known auto‐immune disorder, twin pregnancies, diabetes.
Interventions	Exp: aspirin 100 mg/day, taken in the evening from 8‐10 weeks' gestation to 36 weeks' gestation Control: unclear ‐ refer to the non‐treated group most of the time, but refer to placebo group once in paper.
Outcomes	Women: maternal complications (gestation hypertensive disorders). Babies: gestation length, newborn weight, fetal complications.
Notes	Trial conducted in Blida Hospital, Algeria.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomization for treatment (using anonymous sealed envelopes)" Insufficient information about the sequence generation process to permit judgement.
Allocation concealment (selection bias)	Unclear risk	Quote:"anonymous sealed envelopes". No information about whether opaque or numbered.
Blinding (performance bias and detection bias) All outcomes	High risk	Quote:"The patient and the study promoter were not blinded to the conditions of treatment."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Appears to be no missing outcome data, i.e. number randomised = number reported in outcomes.
Selective reporting (reporting bias)	Low risk	Protocol not available but all expected outcomes are reported.
Other bias	Unclear risk	Baseline characteristics: Quote:"The control and treated groups were not statistically different with respect to age, body mass index, gestity and parity (Table 1)." However, did not report baseline BP measures.