ISRCTN24531848.

Methods	Participants undergoing primary total knee replacement were randomised to one of two groups. The method of randomisation and allocation concealment is not described. The blinding status of participants, study personnel, and outcome assessors is not described.
Participants	120 participants undergoing primary total knee replacement were randomised to one of two groups: Group A (Control group): N = 60 Group B (Autotransfusion group): N = 60
Interventions	Group A (Control group): received homologous transfusion Group B (Autotransfusion group): received wound drained autotransfusion
Outcomes	The outcome measures used are not known
Notes	Transfusion protocol: it is not known whether a transfusion protocol was used. Prospective registration status: the study was registered retrospectively on ISRCTN on 12 September 2003. Ethical approval: it is not known whether ethical approval was received. Language: information on the trial registration on ISRCTN is in English. Reason for awaiting classification status: the study corresponds to a trial registration record on ISRCTN, which states the study is completed. There is insufficient information available to determine whether the study meets inclusion criteria.