Four trials that were not combined in meta-analyses suggested that extracts with high ( > 30 mg/d ) levels of genistein consistently reduced the frequency of hot flushes .
BACKGROUND Vasomotor symptoms , such as hot flushes and night sweats , are very common during the menopausal transition .
Hormone therapy has traditionally been used as a highly effective treatment , but concerns about increased risk of some chronic diseases have markedly increased the interest of women in alternative treatments .
Some of the most popular of these treatments are foods or supplements enriched with phytoestrogens-plant-derived chemicals that have estrogenic action .
OBJECTIVES To assess the efficacy , safety and acceptability of food products , extracts and dietary supplements containing high levels of phytoestrogens when compared with no treatment , placebo or hormone therapy for the amelioration of vasomotor menopausal symptoms ( such as hot flushes and night sweats ) in perimenopausal and postmenopausal women .
Multiplicity in randomised trials II: subgroup and interim analyses
Subgroup analyses can pose serious multiplicity concerns . By testing enough subgroups , a false-positive result will probably emerge by chance alone . Investigators might undertake many analyses but only report the significant effects , distorting the medical literature . In general , we discourage subgroup analyses . However , if they are necessary , research ers should do statistical tests of interaction , rather than analyse every separate subgroup . Investigators can not avoid interim analyses when data monitoring is indicated . However , repeatedly testing at every interim raises multiplicity concerns , and not accounting for multiplicity escalates the false-positive error . Statistical stopping methods must be used . The O'Brien-Fleming and Peto group sequential stopping methods are easily implemented and preserve the intended alpha level and power . Both adopt stringent criteria ( low nominal p values ) during the interim analyses . Implementing a trial under these stopping rules resembles a conventional trial , with the exception that it can be terminated early should a treatment prove greatly superior . Investigators and readers , however , need to grasp that the estimated treatment effects are prone to exaggeration , a r and om high , with early stopping
Four trials that were not combined in meta-analyses suggested that extracts with high ( > 30 mg/d ) levels of genistein consistently reduced the frequency of hot flushes .
BACKGROUND Vasomotor symptoms , such as hot flushes and night sweats , are very common during the menopausal transition .
Hormone therapy has traditionally been used as a highly effective treatment , but concerns about increased risk of some chronic diseases have markedly increased the interest of women in alternative treatments .
Some of the most popular of these treatments are foods or supplements enriched with phytoestrogens-plant-derived chemicals that have estrogenic action .
OBJECTIVES To assess the efficacy , safety and acceptability of food products , extracts and dietary supplements containing high levels of phytoestrogens when compared with no treatment , placebo or hormone therapy for the amelioration of vasomotor menopausal symptoms ( such as hot flushes and night sweats ) in perimenopausal and postmenopausal women .