Cameron 1990.

Study characteristics
Methods	Study design: parallel RCT Study duration: November 1981 to February 1985 Duration of follow‐up: to 49 months
Participants	Setting: multicentre Country: UK Inclusion criteria: biopsy‐proven IMN with nephrotic syndrome Baseline characteristics Pathology stage: 89/103 biopsies were reviewed and 70 were graded (4 as I, 32 as II, 26 as III, and 8 as IV) Mean proteinuria ± SD (g/24 hours): treatment group (10.8 ± 5.9); control group (10.4 ± 5.3) Hypertension: treatment group (9/52); control group (16/51) Mean serum albumin ± SD (g/L): treatment group (26 ± 6); group (25 ± 5) Mean SCr ± SD (μmol/L): treatment group (114 ± 42); control group (115 ± 43) Mean GFR ± SD (mL/min): treatment group (87 ± 30); control group (89 ± 34) Baseline declining kidney function: 13/103 patients with an initial SCr ≥ 150 μmol/L Previous immunosuppressive status: no Number (randomised/analysed): treatment group (52/43); control group (51/43) Mean age ± SD (years): treatment group (45 ± 11.6); control group (44 ± 12.1) Sex (M/F): treatment group (43/9); control group (43/8) Exclusion criteria: aged > 65 years
Interventions	Treatment group Prednisolone: 125 mg was given every alternate day for 8 weeks. Patients who weighed more than 80 kg received 150 mg on alternative days Control group Placebo: identical tablets as prednisolone for 8 weeks
Outcomes	Death ESKD 50% or 100% SCr increase Final Cr Final GFR Partial or complete remission Final proteinuria Side effects leading to patient withdrawal or hospitalisation.
Notes	Funding information: not reported Confounding factors: at the last follow‐up (49 months) a higher proportion of females were in remission or had stable function than corresponding males (P = 0.012)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote "Randomization was performed centrally, and coded tablets given locally from bottles supplied from the co‐ordinator"
Allocation concealment (selection bias)	Low risk	Randomisation method described could not allow investigators/participants to know or influence intervention group before eligible participant entered in the study
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Identical tablets were used, that contained either 5 mg of prednisolone or placebo
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information to permit judgement
Incomplete outcome data (attrition bias) All outcomes	Low risk	4 patients (8%) in the treatment group were lost at 4, 6, 21, and 24 months and 3 (6%) in the placebo group at 9, 18, and 21 months. Their data to the point of loss have been included in the analysis on an intention‐to‐treat basis. No patient lost was in remission or had a plasma Cr of over 400 μmol/L when lost. Thus, missing outcome data balanced in numbers across intervention groups and have been imputed using appropriate methods
Selective reporting (reporting bias)	Low risk	The study protocol was not available but it was clear that the published reports included all expected outcomes, including those that were pre‐specified
Other bias	Low risk	The study appeared to be free of other sources of bias