Table 1. Characteristic of the included studies.

Source	Population	No. of Patients	Interventions	Baseline renal function and/or proteinuria	Follow up (month)
Katafuchi R 2008 [28]	Been biopsied with primary IgA nephropathy	702	(1) Methylprednisolone 1 g/day3 days plus Prednisolone 30 mg/day2 years(2) Prednisolone 60 mg/day4 weeks and then tapered off within 1 year, Prednisolone 20 mg or 30 mg/day1 month and Prednisolone was tapered and maintained for at least 2 years(3) Anti-platelet agent or with no medication	Serum creatinine(0.980.58 mg/dl)	62
Koike M 2008[29]	Light microscopic findings	48	(1) Prednisolone was 0.4 mg/kgBW/day (20–30 mg/day) 4 weeks, then reduced to 10–20 mg on alternate days12 months and 5–10 mg on alternate days for a subsequent year(2) dipyridamole or zilazep hydrochloride 150 or 300 mg/day	Steroid group serum creatinine was 0.920.26 mg/dl and non-steroid group was 1.150.35 mg/dl	24
Pozzi C 2004[30]	Biopsy-proven Ig A nephropathy	86	(1) Methylprednisolone 1 g/day3 days and again 2 and 4 months later, other day oral prednisolone 0.5 mg/kg6 months(2) Supportive treatment	Urinary protein excretion levels of 1–3.5 g/d	120
Moriyama T 2004[31]	Been diagnosed based on light-microscopic findings	60	(1) Prednisolone 0.8 mg/kg/day4 weeks, then reduced to 20–30 mg on alternate days12 months and 20 mg on alternate days12 months(2) Anti-platelet agent	Steroid group serum creatinine was 1.210.44 mg/dl and non-steroid group was 1.270.33 mg/dl	54.6
Katafuchi R 2003[32]	Biopsy-proven new Ig A nephropathy	103	(1) Prednisolone 20 mg/day1 month, 15 mg/day1 month, 10 mg/day1 month, 7.5 mg/day3 months and 5 mg/day18 months(2) dipyridamole 150 or 300 mg/day	Steroid group serum creatinine was 0.920.24 mg/dl and non-steroid group was 0.910.21 mg/dl	64.5
Shoji T 2000[33]	Biopsy-proven Ig A nephropathy	21	(1) Prednisolone 0.8 mg/kg/day, then reduced to 0.4 mg/kg/day 1 month and tapered to 10 mg1 year(2) dipyridamole 300 mg/day1 year	Proteinuria<1.5 g/day of protein and serum creatinine<1.5 mg/dl	12
K.N.Lai 1986[34]	Presence of IgA deposits in the mesangium	34	(1) Prednisolone 40–60 mg/day8 weeks, then tapered by half4 months(2) no corticosteroid therapy	Steroid group urinary protein was 6.52.8 gm/day and non-steroid group was 4.71.4 gm/day	38
Kobayashi Y 1996[35]	Fulfilled the three conditions defining the early stage of progressive Ig A nephropathy	90	(1) Prednisolone 40 mg/day4 weeks, 30 mg/day8 weeks, 25 mg/day8 weeks, 20 mg/day8 weeks, then 15 mg/day6 months and thereafter was further tapered(2) dipyridamole 300 mg/day	Creatinine clearance>70 ml/min	120
Welch TR 1992[36]	Been proved Ig A nephropathy	20	(1) Prednisolone 2 mg/kg(<80 mg)12 weeks(2) placebo	Serum creatinine<140umol/l	3
Kobayashi Y 1988[37]	Ig A nephropathy with primary glomerular deseases	96	(1) Prednisolone 40 mg/day4 weeks, 30 mg/day8 weeks, 25 mg/day8 weeks, 20 mg/day8 weeks, then 15 mg/day6 months and thereafter further tapered on a gradual basis(2) Non-steroidal anti-inflammatory and/or anti-thrombocyte drugs	Proteinuria>1.0 g/day	48
Julian BA 1993[38]	Biopsy-proven Ig A nephropathy	35	(1) Alternate day prednisolone 60 mg3 months(2) No treatment	Creatinine clearance>25 ml/min	24
Uzu T 2003[39]	Biopsy-proven Ig A nephropathy	45	(1) Methylprednisolone 1 g/day3 day, then oral prednisolone 40 mg/day4 weeks, 30 mg/day4 weeks, 25 mg/day4 weeks, 20 mg/day4 weeks, 15 mg/day2 months, and gradual reduction in 6 months(2) Supportive treatment	Serum creatinine<106umol/l	36
Manno C[21]	Biopsy-proven Ig A nephropathy	97	(1) Prednisolone 1.0 mg/kg/day2 months, then 0.2 mg/kg/day 4 months(2) ramipril	Serum creatinine was 1.08 mg/dl	96
Lv J[22]	Biopsy-proven Ig A nephropathy	63	(1) oral prednisone 0.8 to 1.0 mg/kg/day 8 weeks, then the dose was tapered by 5 to 10 mg every 2 weeks(2) cilazapril	Serum creatinine was 1.1 mg/dl	48
Locatelli F 2001[40]	Biopsy-proven Ig A nephropathy	86	(1) Methylprednisolone 1 g/day3 day at the beginning of vmonths 1, 3, and 5, and again two and four months later, oral prednisolone 0.5 mg/kg6 months(2) Supportive treatment	Plasma creatinine levels<1.5 ml/dL	64