Research Article
An Estrogen Model: The Relationship between Body Mass Index, Menopausal Status, Estrogen Replacement Therapy, and Breast Cancer Risk
Table 1
Studies used to validate the model.
| Study | Type of study | Baseline cohort size | Mean years of followup | Use for model validation |
| Pooling Project [16] | Pooled reanalysis of 7 cohort studies | Total* | 337,819 | 3–8 | Premenopausal and postmenopausal models |
|
EPIC [17] | Prospective cohort study | Premenopausal | 73,542 | 4.7 | Premenopausal and postmenopausal models | Postmenopausal | | non-HRT users | 79,030 |
| Million Women Study [14, 18] | Prospective cohort study | Premenopausal | 63,153 | 5.4 | Premenopausal, postmenopausal, and ERT models | Postmenopausal | | never users of HRT | 392,757 | current users of HRT | 285,987 |
|
CPS-II [19] | Prospective cohort study | Postmenopausal | | 8 | Postmenopausal model | non-HRT users | 41,159 |
| WHI Observational Study [20] | Prospective cohort study | Postmenopausal | | 2.9 | Postmenopausal model | never users of HRT | 32,547 |
| WHI Estrogen-Alone Trial [21] | Randomized controlled trial | Postmenopausal | | 7.1 | ERT model | non-HRT users | 5,429 | ERT users | 5,310 |
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*Separate numbers of postmenopausal and premenopausal women included in the Pooling Project were unavailable.
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