Table 1. Characteristics of the 5 included articles on BMI and mortality of RCC.

Author, year country	Study type	Mean/ median age,	Follow up	Study size, number of cases	BMI (Kg/m2) cases	RR (95% CI)	Adjustment factors	NOS
Reeves et al. 2007 UK	Cohort	50–64	7	1222630	< 22.5 63 22.5–24.9 81 25.0–27.4 80 27.5–29.5 58 ≥ 30 100 per 10 units	1.01 (0.79–1.30) 1.00 (0.80–1.24) 1.14 (0.92–1.42) 1.30 (1.01–1.68) 1.71 (1.39–2.09) 1.65 (1.28–2.13	Age, socio economic status, smoking, alcohol, physical activity, region, years since menopause and use of hormone replacement therapy, geographical reproductive history,	7
Batty et al. 2005 Austrilia	Cohort	55.9	35	18403	18.5–24.9 36 25.0–29.9 20 ≥30 5	1.0 0.58 (0.32–1.04) 1.20 (0.41–3.52)	Age, physical activity, plus employment grade, smoking, marital status, disease at entry, weight loss in the last year, height, FEV1, blood pressure-lowering medication, triceps skin fold thickness, systolic blood pressure, plasma cholesterol, glucose intolerance and diabetes status.	8
Calle et al. 2003 USA	Cohort	57	16	900053 M:404576 W:495477	M 18.5–24.9 305 25.0–29.9 437 30.0–34.9 81 ≥ 35 14 W 18.5–24.9 243 25.0–29.9 153 30.0–34.9 55 35.0–39.9 12 ≥ 40 10	M 1.00 1.18 (1.02–1.37) 1.36 (1.06–1.74) 1.70 (0.99–2.92) W 1.00 1.33 (1.08–1.63) 1.66 (1.23–2.24) 1.70 (0.94–3.05) 4.75 (2.50–9.04)	Age, education, smoking status, physical activity, number of cigarettes, fat consumption, alcohol, marital status, aspirin use, vegetables consumption.	8
Parr et al 2010 Asia-Pacific	Cohort	48	4	424519	12.0–18.4 2 18.5–24.9 29 25.0–29.9 27 30.0–60.0 9 Per 5 units (> 18.5)	1.17 (0.28–4.97) 1.00 (0.70–1.43) 1.42 (0.96–2.12) 1.59 (0.78–3.24) 1.20 (0.86–1.66)	Age and smoking	7
Heath et al. 1997 USA	Cohort	56–57	7	998904	M < 20.7 4 20.7–24.6 62 24.7–27.7 81 27.8–31.0 48 ≥31.1 17 W < 19.1 2 19.1–21.9 18 22.0–27.2 57 27.3–32.2 33 ≥ 32.3 13	M 0.6 (0.2–1.5) 1.0 1.1 (0.8–1.6) 1.6 (1.1–2.3) 1.6 (0.9–2.7) W 0.6 (0.1–2.5) 1.0 1.5 (0.9–2.6) 2.5 (1.4–4.4) 3.15 (1.5–6.4)	Adjusted age	7