Because our evaluation focused on sub-Saharan African countries, the northern African countries of Morocco and Sudan were not included. Since risk in lower-income countries could be different, we did not include middle-income South Africa. We analyzed 717 cases and had >80% power to detect a relative incidence of ≥2.5 within 1–7 days after the first dose. This is the largest post-licensure intussusception evaluation to date. Since our goal was to assess the possible association between rotavirus vaccination and intussusception, we did not investigate other risk factors or causes for intussusception. The self-controlled case-series (SCCS) methodology automatically controls for confounding by fixed risk factors. We may have not captured all intussusception cases and cannot estimate population-based rates. However, because the SCCS methodology depends on the timing of intussusception relative to vaccination, comparison of intussusception rates is not required. Also, the under-identification of intussusception cases would not bias our results unless we selectively missed cases of intussusception immediately following vaccination; we do not believe that this occurred.