Re: 'a case-control study of oral contraceptive use and incident breast cancer'.

摘要

In their recent case-control study of breast cancer risk in relation to oral contraceptive (OC) use, Rosenberg et al. (1) reported a significantly increased risk for women exposed for 1 year or more relative to less than 1 year and never use combined (multivariable odds ratio = 1.5, 95% confidence interval: 1.2,1.8). As best I am aware, the use of a reference category of OC use of less than 1 year, combined with never use, is without precedent.