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. Author manuscript; available in PMC: 2014 Apr 10.
Published in final edited form as: Cochrane Database Syst Rev. 2009 Apr 15;(2):CD000111. doi: 10.1002/14651858.CD000111.pub3
Methods Randomisation by sealed opaque, sequentially numbered envelopes containing the code.
Prepared in random blocks of 10, stratified for parity.
Methodological qualities:

  1. selection bias: none;

  2. performance bias: high risk of bias could have been introduced because researcher cannot be blind to group allocation after randomisation

  3. exclusion bias: low risk of bias as all women received their allocated treatment. Analysed according to intention to treat. 1 lost to follow-up;

  4. bias conclusion: moderate bias. 1 or more criteria partially met. May raise some doubt about the results. Women were randomised at full dilatation of bearing down efforts
Participants Study group: n = 60.
Control group: n = 60.
Academic teaching hospital, Johannesburg, South Africa.
Inclusion criteria:
gestation > 36 weeks;
low risk;
singleton;
cephalic presentation;
active phase of labour;
normal FHR pattern;
ambulation and analgesics were allowed;
able to read and understand English.
No immersion of water was used during the first stage of labour
Interventions Study group: allocated to oval bath tub which contained about 220 L of water. Temperature 34-38 degrees Celsius. Women were allowed to use different postures in the bath.
Control group: care the same as study group but they were not allowed to use a bath for birth. All care was the same. Consent obtained early in labour but randomisation took place at full second stage.
Same main caregivers for all women.
Outcomes Maternal outcomes:
*maternal experience and satisfaction of labour;
*pain;
*use of analgesia/anaesthesia;
*augmentation of labour;
*blood pressure;
*pulse;
*duration of labour and birth;
*mode of delivery;
*trauma to the birth canal requiring suturing;
*blood loss;
maternal infection;
*postpartum depression.
Fetal outcomes:
*abnormal FHR patterns needing intervention.
Neonatal outcomes:
*neonatal condition;
*admittance to NICU or high dependency care unit;
*temperature at birth;
*perinatal deaths;
delivered in OP position;
gravida;
age;
birthweight;
duration in bath.
Notes Done in South Africa. 1999.
Risk of bias
Bias Authors’ judgement Support for judgement
Random sequence generation (selection bias) High risk Not stated only says prepared in random blocks of 10, stratified for parity. Blocks of 10 have potential for breaking concealment for at least participant in each block
Allocation concealment (selection bias) Low risk Sealed opaque, sequentially numbered envelopes containing the code
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 Information from approach to women (133) to allocation (60+60); all women completed trial but 3 in control group to not complete follow-up questionnaire
Selective reporting (reporting bias) Low risk All outcomes identified in methods are reported. Thesis made available with very detailed reporting
Other bias Unclear risk All women regardless of group had 1-to-1 care from researcher