Related Experiment Video
Updated: Aug 4, 2026

Time-lapse Imaging of Primary Preneoplastic Mammary Epithelial Cells Derived from Genetically Engineered Mouse Models of Breast Cancer
Published on: February 8, 2013
Bias in breast cancer analyses due to error in age at menopause
B Rockhill1, G A Colditz, B Rosner
1Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Abstract:
With the use of data from the Nurses' Health Study, the authors confirm the recent argument by Pike et al. (Am J Epidemiol 1998;147:718-21) that various ways of assigning ages at menopause to women with simple hysterectomy produce relative risks for the effect of hormone replacement therapy (HRT) that are biased downward. Different methods of including women with simple hysterectomy consistently produced relative risks for the association between a 1-year increase in duration of HRT use and breast cancer that were underestimates compared with the relative risk obtained when these women were excluded from analysis. The authors used longitudinal data on recalled age at menopause to demonstrate another source of error related to age at menopause: error in recall of age at menopause that increases with time since menopause.
Related Concept Videos
Nondisjunction
Bias
In statistics, a sampling bias is created when a sample is collected from a population, and some members of the population are not as likely to be chosen as others (remember, each member...
Confounding in Epidemiological Studies
Bias in Epidemiological Studies
Assumptions of Survival Analysis
Cancer Survival Analysis

