The reporting quality of SRs has improved 3 y after publication of SR reporting st and ards , but the reporting of nutrition variables has not .
Improved adherence to consensus methods and reporting st and ards should improve the utility of nutrition SRs
BACKGROUND The quality of nutrition-related systematic review s ( SRs ) is an unstudied but important factor affecting their usefulness .
OBJECTIVES The objectives were to evaluate the reporting quality of published SRs and to identify areas of improvement .
The SU.VI.MAX Study: a randomized, placebo-controlled trial of the health effects of antioxidant vitamins and minerals.
BACKGROUND It has been suggested that a low dietary intake of antioxidant vitamins and minerals increases the incidence rate of cardiovascular disease and cancer . To date , however , the published results of r and omized , placebo-controlled trials of supplements containing antioxidant nutrients have not provided clear evidence of a beneficial effect . We tested the efficacy of nutritional doses of supplementation with a combination of antioxidant vitamins and minerals in reducing the incidence of cancer and ischemic cardiovascular disease in the general population . METHODS The Supplementation en Vitamines et Mineraux Antioxydants ( SU.VI.MAX ) study is a r and omized , double-blind , placebo-controlled primary prevention trial . A total of 13 017 French adults ( 7876 women aged 35 - 60 years and 5141 men aged 45 - 60 years ) were included . All participants took a single daily capsule of a combination of 120 mg of ascorbic acid , 30 mg of vitamin E , 6 mg of beta carotene , 100 mug of selenium , and 20 mg of zinc , or a placebo . Median follow-up time was 7.5 years . RESULTS No major differences were detected between the groups in total cancer incidence ( 267 [ 4.1 % ] for the study group vs 295 [ 4.5 % ] for the placebo group ) , ischemic cardiovascular disease incidence ( 134 [ 2.1 % ] vs 137[2.1 % ] ) , or all-cause mortality ( 76 [ 1.2 % ] vs 98 [ 1.5 % ] ) . However , a significant interaction between sex and group effects on cancer incidence was found ( P = .004 ) . Sex-stratified analysis showed a protective effect of antioxidants in men ( relative risk , 0.69 [ 95 % confidence interval [ CI ] , 0.53 - 0.91 ] ) but not in women ( relative risk , 1.04 [ 95 % CI , 0.85 - 1.29 ] ) . A similar trend was observed for all-cause mortality ( relative risk , 0.63 [ 95 % CI , 0.42 - 0.93 ] in men vs 1.03 [ 95 % CI , 0.64 - 1.63 ] in women ; P = .11 for interaction ) . CONCLUSIONS After 7.5 years , low-dose antioxidant supplementation lowered total cancer incidence and all-cause mortality in men but not in women . Supplementation may be effective in men only because of their lower baseline status of certain antioxidants , especially of beta carotene
The reporting quality of SRs has improved 3 y after publication of SR reporting st and ards , but the reporting of nutrition variables has not .
Improved adherence to consensus methods and reporting st and ards should improve the utility of nutrition SRs
BACKGROUND The quality of nutrition-related systematic review s ( SRs ) is an unstudied but important factor affecting their usefulness .
OBJECTIVES The objectives were to evaluate the reporting quality of published SRs and to identify areas of improvement .