Chantrapitak 2009.

Study characteristics
Methods	A parallel group randomised trial. Setting: hospital setting in Bangkok hospital, Thailand.
Participants	Women diagnosed with primary PPH following vaginal birth. PPH was defined as "blood loss > 500ml after delivery" p 601 Gestational age 28 to 42 weeks 66 women were randomised but 2 excluded "due to cervical tear and extensive birth canal tear" p 601. Therefore 64 women were then included in the study (32 in each group).
Interventions	Experiemtal: external lower uterine compression (either by grasping the uterus through a lax abdominal wall or compressing the uterus against the sacrum and lower vertebrae) for a duration of 10 minutes Control: usual care consisting of "massage, oxytocin (10‐20 units in 1000 ml of intravenous solution, 200 ml/min), intravenous ergometrine (Methergin®, 0.2 mg), placed cold pack on uterus, and urinary catheterisation" p 601.
Outcomes	Measured blood loss (mL): before treatment (mean) and also after treatment (presented as medians) Blood transfusion Use of additional uterotonic agent to control bleeding (prostaglandin [Nalador])
Notes	Trial authors' declarations of interest: not mentioned Sources of trial funding: not mentioned Trial dates: January to August 2008 Informed consent obtained?: not mentioned in the trial report Ethics approval obtained?: not mentioned in the trial report Did we attempt to contact the trial authors?: no
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	States that participants were "equally divided into two groups and the treatment method was randomly assigned to each patients" but no further information given
Allocation concealment (selection bias)	Unclear risk	No information about allocation concealment provided in the trial report
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not mentioned but it would not be possible to blind this intervention. The paper suggests that all (n = 10) blood transfusions were administered based on haematocrit measurement, i.e. based on objective measure that would probably not be affected by lack of blinding in personnel, "Ten received blood transfusion because of underlying anemia (Hct less than 33%)" (p 602). This paper only reports 2 primary outcomes, volume of blood lost and blood transfusion and it is possible that a lack of blinding of either participants or personnel could have affected these outcomes and decision‐making around some co‐interventions
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	"Well trained nurses were assigned to record the results in the record form", p 601. Insufficient information to assess whether outcome assessors were blinded. "All soaking drapes and blood in basket were weighed", p 601. Blood loss assessed by weighing, although there could have been room for outcome assessors to influence this measurement. A lack of blinding could have influenced outcome assessment for blood loss (because measurement of the assessment of amount of blood lost is not completely objective)
Incomplete outcome data (attrition bias) All outcomes	High risk	There are 2 women with cervical and vaginal tears whose outcomes are not reported. It is unclear whether these were excluded before or after randomisation. However, cervical and vaginal tears are only usually found upon detailed examination after failure of primary treatment (in this case oxytocics plus uterine compression). It seems likely therefore that they were excluded AFTER randomisation. Otherwise the outcomes for all the other 64 participants were reported
Selective reporting (reporting bias)	Unclear risk	No mention of a protocol but outcome reporting bias is not apparent
Other bias	Low risk	No other sources of bias were apparent