Healy 1994.

Study characteristics
Methods	Design: RCT, parallel three‐arm, multicentre study Setting: four US medical centres Recruitment: recruitment and study dates not reported Maximum follow‐up: duration of hospital stay
Participants	128 participants undergoing total hip arthroplasty, total knee arthroplasty, or spine fusion were randomly allocated to one of three groups: Group 1 (Orth‐Evac) (Cell salvage/intervention group): N = 44. M:F 18:26. Mean (range) age 67.9 (41 to 82) Group 2 (Solcotrans) (Cell salvage/intervention group): N = 40; M:F 20:20. Mean (range) age 66.3 (54 to 82) Group 3 (Banked blood) (Control/no cell salvage group): N = 44; M/F 23:21. Mean age 62.5. The three groups were similar with regard to age, height, weight, and gender.
Interventions	Group 1 (Orth‐Evac) (Cell salvage/intervention group): the cell salvage (Orth‐Evac) group received autologous shed blood reinfusion collected from wound drainage by an Orth‐evac device (Deknatal, Fall River, Massachusettes, USA). Group 2 (Solcotrans) (Cell salvage/intervention group): the cell salvage (Solcotrans) group received autologous shed blood reinfusion collected from wound drainage by a Solcotrans device (Smith & Nephew, Memphis, Tennessee, USA). Group 3 (Banked blood) (Control/no cell salvage group): the control group received either autologous pre‐donated blood or allogeneic banked blood. In control participants, a standard wound drainage system (Hemovac) was used, and these participants received liquid‐preserved autologous pre‐donated blood or allogeneic blood filtered with a standard 170 µm screen filter. NB: participants randomised to the cell salvage groups (Group 1 and Group 2) were randomly assigned to one of two infusion filters (Pall 40 µm screen filter or Pall RC100 polyester filter) for the transfusion phase of the study. With the Solcotrans drainage system, 40 mL acid citrate dextrose (ACD) was used. No anticoagulant was added with the Ortho‐evac drainage system.
Outcomes	Outcomes reported: amount of blood collected by the cell saver, amount of blood re‐transfused from the cell saver, number of participants transfused allogeneic blood, amount of allogeneic blood transfused, adverse events
Notes	Transfusion protocol: use of a transfusion protocol is not reported. Prospective registration status: the study was published prior to 2010. Ethical approval: it is not clear whether the study was approved by an ethics committee or institutional review board. Language of publication: English Study groups: for the purpose of our review, Group 1 (Orth‐Evac) and Group 2 (Solcotrans) were used as the cell salvage/intervention group. Group 3 (banked blood) was used as the control/no cell salvage group. Trial funding: not reported Conflicts of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method used to generate allocation sequences was not described.
Allocation concealment (selection bias)	Unclear risk	Method used to conceal treatment allocation was unclear.
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 clear transfusion protocol in place: homologous packed red cells were transfused intraoperatively or postoperatively when the haematocrit fell below 30%.
Blinding of participants and personnel (performance bias) Subjective: all other outcomes	High risk	The blinding status of participants and personnel was not described
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	High risk	The blinding status of outcome assessors was not described and there was no transfusion protocol in place
Incomplete outcome data (attrition bias) All outcomes	High risk	8/84 who had drainage of < 250 mL and one participant whose shed blood was stored at room temperature for longer than 6 hours were not reinfused and were excluded from the study. Unbalanced across groups
Selective reporting (reporting bias)	Unclear risk	No trial registration or published protocol is available to compare
Other bias	Unclear risk	No baseline imbalance noted. Funding and conflicts not reported