Fig. 1From: Effectiveness of the 10-valent pneumococcal conjugate vaccine on pediatric pneumonia confirmed by ultrasound: a matched case–control studyFlow diagram for children screened by ultrasound and those enrolled into the matched case–control study. We include eligibility criteria for cases, the number of matching sets (which is equal to the number of cases) and the number of control children. Only 10 sets (0.5%) had missing dataBack to article page