Methods	Randomised when regular contractions and eligible. Sealed opaque envelopes. Methodological qualities: selection bias: low risk; adequate concealment at time of randomisation; performance bias: high risk of bias; could have been introduced because researcher cannot be blind to group allocation after randomisation; exclusion bias: moderate risk of bias; 46 were excluded and 11.1% (KH) and 4.4% (LH) did not use tub; bias conclusion: moderate bias; 1 or more criteria partially met. May raise some doubt about the results
Participants	Study group: KH: n = 364. OH: n = 95; LH: n = 153; total = 612. Control group: KH: n = 376; OH: n = 97; LH: n =152; total = 625. Inclusion criteria: gestation > 35 weeks; previous CS included (VBAC); twins included; active labour > 3 cm cervical dilatation; ruptured membranes on entry also eligible. Ambulation, analgesics and anaesthesia were allowed. 42 were withdrawn (15 from OH, 21 from LH and 6 KH) no indication for study/control group split for withdraws
Interventions	Study group: warm bath; no information on management of care for either group; no information on water temperature or bath size. Control group: shower allowed. Water use in first stage, no mention of 1-to-1 second care or not
Outcomes	Maternal outcomes: *use of analgesia/anaesthesia; *mode of delivery; *trauma to the birth canal requiring suturing. Neonatal outcomes: *neonatal condition; *admittance to NICU or high dependency care unit. Additional outcomes: secondary arrest and delivered in OP position.
Notes	3 obstetric units in Sweden - 1992-1995.
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not indicated.
Allocation concealment (selection bias)	Low risk	Sealed opaque envelopes.
Blinding (performance bias and detection bias) All outcomes	High risk	High risk of bias could have been introduced because women, carers and researcher cannot be blind to group allocation after randomisation due to the nature of the intervention
Incomplete outcome data (attrition bias) All outcomes	Low risk	From a total of 1279 women, 42 were excluded across both groups and all centres for obstetric reasons
Selective reporting (reporting bias)	Low risk	All outcomes mentioned in methods are reported, although detailed results only given for main outcomes, others just stated as not significant in the text
Other bias	Low risk	Study was started in 1 unit then after 2 years 2 further obstetric units were involved to achieve the required sample size. Nil else noted