Sanfilippo 1985.

Methods	Design: Parallel group RCT Country: USA Multicentre study: No Setting: Hospital Follow‐up: 1 year Unit of allocation: Patients Unit of analysis: Patients
Participants	Inclusion criteria: All potential cadaver renal allograft recipients Exclusion criteria: Not clearly reported Patients enrolled: 126 Patients randomised: 107 PRBCs group: 42 Leukocyte poor red cells group: 45 Mixed group: 20 Patients transfused: 107 Patients considered for the analysis: 107 Main characteristics of patients included in full analysis were not fully stated: Quote: "there were no significant differences between transfusion groups in terms of demographic factors, including number of transfusions, age, race, sex, degree of HLA match, number of diabetics or the use of ATG posttransplant" (Page 117).
Interventions	PRBCs group: PRBCs. Leukocyte poor red cells group: Leukocyte poor red cell (the timing of leukoreduction is not reported). Cointerventions: "All transplant recipients received conventional maintenance immunosuppressive therapy with azathioprine and prednisone, and antithymocyte globulin (ATG) and/or bolus methylprednisolone was used for the treatment of rejection episodes" (Page 117).
Outcomes	This RCT did not specify by primary or secondary outcomes. Panel reactive antibody (PRA) levels: percent of panel cells showing at least 20% lysis with patients' serum, regardless of serum dilution, as determined by the antiglobulin modification. Allograft and patient survival.
Notes	Trial registration: Not reported. Funding: National Kidney Foundation of North Carolina Role of sponsor: Not stated A priori sample size estimation: No Conducted: Between September 1980 and June 1982 Declared conflicts of interest: Not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "...after obtaining informed consent, patients were randomly assigned to receive" (Page 116). Comment: Insufficient information to permit judgement of ‘low risk’ or ‘high risk’.
Allocation concealment (selection bias)	Unclear risk	Quote: "...after obtaining informed consent, patients were randomly assigned to receive..." (Page 116). Comment: Insufficient information to permit judgement of ‘low risk’ or ‘high risk’.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: Insufficient information to permit judgement of ‘low risk’ or ‘high risk’.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: Insufficient information to permit judgement of ‘low risk’ or ‘high risk’.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: Insufficient information to permit judgement of ‘low risk’ or ‘high risk’.
Selective reporting (reporting bias)	High risk	Comment: The study report fails to include results for a key outcome that would be expected to have been reported for such a study.
Other bias	High risk	Design bias.