Breast cancer is the most common cancer among women in North Africa. Women in this region have unique reproductive profiles. It is essential to obtain reliable information on reproductive histories to help better understand the relationship between reductive health and breast cancer. We tested the reliability of a reproductive history-based questionnaire. We interviewed 25 breast cancer patients and 25 non-cancer controls from hospitals in Morocco and Egypt about their reproductive history in colloquial Arabic. The questions included pregnancy history, breastfeeding practices, menstruation, contraceptive use and knowledge of breast screening and re-interviewed the same women after 2 weeks. Two-way paired t-test was used to compare observed mean changes in response, and the Fishers Exact test was used for small-cell data. Pearson's correlation test was used to estimate the correlation of subjects' responses to continuous questions between the first and second interview. For categorical questions, percentage of agreement was calculated along with Cohen's Kappa Coefficient values. Moroccan subjects showed good to excellent agreement for responses to all demographic and reproductive questions (r = 0.87 to 0.99). Egyptian subjects had excellent agreement for these questions(r = 0.87 to 0.99), except for those regarding duration of oral contraceptive pill use and reported age at menarche (r = 0.72 and 0.59, respectively). We showed highly correlated responses to most reproductive questions. Duration of contraception use and age at first pregnancy elicited slightly less than reliable responses. In Egypt, responses relating to self-reported age at menarche were less reliable than those given by Moroccan subjects. Future epidemiological studies should take these differences into account when constructing reproductive history questionnaires.
Keywords: Breast Cancer; Egypt; Morocco; Reliability; Reproductive Factors.