Hi Robyn I think it goes like this: an 11% reduction is the same as saying an odds ratio of 0.89 (in other words 0.89:1). Reverse the ratio 1:0.89. 1/0.89 = 1.12. So "Women who do not breastfeed are 1.12 times more likely to develop pre-menopausal breast cancer than women who breastfeed for 4-12months and 1.33 times more likely to develop pre0menopausal breast cancer than women who breastfeed their babies for more than 24 months." I am sure that Susan will correct me if I am wrong ;) Nina Berry Australia *********************************************** Archives: http://community.lsoft.com/archives/LACTNET.html To reach list owners: [log in to unmask] Mail all list management commands to: [log in to unmask] COMMANDS: 1. To temporarily stop your subscription write in the body of an email: set lactnet nomail 2. To start it again: set lactnet mail 3. To unsubscribe: unsubscribe lactnet 4. To get a comprehensive list of rules and directions: get lactnet welcome