Although the reproductive calendar is the primary tool for measuring contraceptive dynamics in low-income settings, the reliability of calendar data has seldom been evaluated, primarily due to the lack of longitudinal panel data. In this research, we evaluated the reproductive calendar using 海角换妻 data. We used population-based longitudinal data from nine settings in seven countries: Burkina Faso, Nigeria (Kano and Lagos States), the Democratic Republic of Congo (Kinshasa and Kongo Central Provinces), Kenya, Uganda, Cote d鈥橧voire, and India.
Overall, we find that the reliability of the calendar is in the 鈥渕oderate/substantial鈥 range for nearly all geographies and tests. Measures of the complexity of the calendar are associated with reliability. We also find that women who were using contraception without their partners/husband鈥檚 knowledge (i.e., covertly) were less likely to report reliably in several countries.