Luo 2016.

Study characteristics
Methods	Design: RCT, parallel two‐arm, multicentre study Setting: 2 hospitals in Guangzhou, China (1 university teaching hospital, 1 regional district hospital) Recruitment: October 2014 to October 2015 Maximum follow‐up: 7 days postoperatively
Participants	A total of 91 participants undergoing total hip arthroplasty (THA) were randomised to one of the following two groups: ABT Group (Cell salvage/intervention group): N = 49. Mean (SD) age 58 (5.7). M:F 27:22. Mean BMI 22.1 Standard drainage group (Control/no cell salvage group): N = 42. Mean (SD) age 61 (6.3). M:F 22:20. Mean BMI 21.8 There was no difference in baseline data between the two groups.
Interventions	ABT Group (Cell salvage/intervention group): the ABT group received a ConstaVac Blood Conservation II (CBCII, Stryker Instruments, Kalamazoo, Michigan, USA) autologous blood transfusion device. Autologous blood collected within the first 6 hours after surgery was collected and reinfused. Blood collected after 6 hours was collected and discarded. The drain was removed when the daily drainage blood level was < 50 mL. Standard drainage group (Control/no cell salvage group): the drain group (control group) received a conventional postoperative vacuum drain, connected to an ordinary drainage bottle. Drainage blood was not re‐transfused and the drain was removed when daily drainage blood level was < 50 mL.
Outcomes	Outcomes reported: intraoperative blood loss, postoperative drainage blood, amount of ABT blood retransfused, adverse events (including fever, chills, dyspnoea, redness, DVT, wound healing)
Notes	Transfusion protocol: use of a transfusion protocol is not reported for this study. Prospective registration status: the study was not prospectively registered on a trials registry. Ethical approval: there is no information available regarding ethical approval of the study. We contacted authors to enquire about this, but received no response. Langauge: English Trial funding: funded by the Panyu Central Hospital of Guangzhou (2014‐Q‐06) and the Technology and Information Department of Panyu (2014‐Z03‐30). Conflicts of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	There is insufficient information provided to make a judgement
Allocation concealment (selection bias)	Unclear risk	There is insufficient information provided to make a judgement
Blinding of participants and personnel (performance bias) Objective outcome: mortality	Low risk	No objective outcomes reported (mortality unlikely to be affected by blinding if reported in future publications)
Blinding of participants and personnel (performance bias) Subjective: transfusion protocol	High risk	No transfusion protocol stated, and excluded those who received allogeneic transfusion, without providing data on those excluded
Blinding of participants and personnel (performance bias) Subjective: all other outcomes	Unclear risk	There is no description of blinding of study participants or personnel: DVT, confirmed diagnostically by ultrasound Doppler carried out on postop day 7. Blood loss – unclear how this was measured. Unclear how lack of blinding may have influenced this outcome.
Blinding of outcome assessment (detection bias) Objective outcomes: mortality and transfusions	Low risk	No objective outcomes reported (mortality unlikely to be affected by blinding if reported in future publications)
Blinding of outcome assessment (detection bias) Subjective outcomes	Unclear risk	There is no description of blinding of study participants or personnel: DVT, confirmed diagnostically by ultrasound Doppler carried out on postop day 7. Blood loss – unclear how this was measured. Unclear how lack of blinding may have influenced this outcome.
Incomplete outcome data (attrition bias) All outcomes	High risk	Patients who received an allogeneic blood transfusion were excluded from the study
Selective reporting (reporting bias)	Unclear risk	No trial registration or published protocol is available to compare
Other bias	Unclear risk	Funding reported (non‐pharma): this study was funded by the Panyu Central Hospital of Guangzhou (2014‐Q‐06) and the Technology and Information Department of Panyu (2014‐Z03‐30). Conflicts of interest not stated. No apparent baseline imbalance. However, as those who were transfused were excluded, it is unclear whether they were included in the baseline characteristics.