Crowther 1991.

Methods	Randomisation and allocation concealment: block randomisation and use of consecutively‐numbered, opaque, sealed envelopes. Researchers involved in treatment allocation were not involved in preparing the randomisation schedule. Blinding of outcome assessment: the paediatricians examining the newborn infants were unaware of the participants' treatment allocation. Documentation of exclusion: no loss to follow‐up
Participants	19 women with a confirmed triplet pregnancy from 24 weeks' gestation onwards attending a special antenatal clinic for multiple pregnancy were recruited into the study. Women with an uncertain gestational age, cervical suture, hypertension, caesarean section scar or antepartum haemorrhage were excluded.
Interventions	Women allocated to the intervention group received bed rest in hospital from 24 weeks' gestation onwards until delivery. Women were encouraged to rest in bed as much as possible although ambulation was allowed. Women allocated to the control group were encouraged to continue their normal activities at home. They were admitted to the hospital only if complications arose such as preterm labour, hypertension, or preterm rupture of membranes. All women received weekly antenatal assessment
Outcomes	Primary outcomes Gestational age at delivery (using Dubowitz scoring) Preterm birth (< 37 weeks' gestation) Light‐for‐gestational age (< 10th centile by local singleton standards) Secondary outcomes Birthweight Perinatal mortality Neonatal and maternal morbidity
Notes	Chorionicity: not reported Sample‐size calculation: not performed Intention‐to‐treat analyses: performed Compliance: no women in the hospitalisation group required leave of absence from the hospital. 6 women (67%) in the control group subsequently required admission to the hospital because of pregnancy complications Location: single centre in Harare, Zimbabwe Timeframe: 1984‐1986
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Block randomisation and use of consecutively numbered, opaque, sealed envelopes. p 64
Allocation concealment (selection bias)	Low risk	"...researchers involved in treatment allocation were not involved in preparing the randomisation schedule." p 64
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Blinding of participants and personnel was not possible due to the type of intervention (hospitalisation and bed rest compared with no activity restriction at home)
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All newborn infants were examined by a paediatrician who was unaware to which group the mother had been allocated." p 64
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up and analysis on an intention‐to‐treat basis
Selective reporting (reporting bias)	Low risk	"The main outcomes were prespecified..." p 64
Other bias	Low risk	The study appears to be free of other sources of bias