Fig. 3
Forest plot of the association between antibodies to pregnancy-associated P. falciparum antigens and peripheral parasitaemia. a Estimates represent the odds of peripheral P. falciparum parasitaemia in Ab responders compared to Ab non-responders, where antibodies were measured at the same time point as parasitaemia (cross-sectional studies). b Estimates of peripheral P. falciparum parasitaemia in Ab responders compared to Ab non-responders, where antibodies were measured at time points prior to parasitaemia determination. Estimates are risk ratios for RCT and cohort studies and odds ratio for the nested case-control study. Estimates are for women of all gravidities included in original studies: Cox et al. [55] included primigravidae only. The timing of antibody and parasitaemia determination is indicated. Estimate for McLean et al. [63] represents IgG3 responders only as total IgG was not available. DBL5 estimates were only combined when study design was the same. Estimates for FCR3 responses at T2/T3 were not combined because I2 = 82.9%. aData supplied by original authors and estimate calculated by current authors; bEstimate calculated by current authors from data in original publication. CC, case control; CS, cross-sectional; ES, estimate; n, number of participants included in estimate; Flow cyto., flow cytometry; nCC, nested case-control; OR, odds ratio; PI time, timing of determination of parasitaemia; pRBC, parasitized red blood cells; RCT, randomized controlled trial; T1, first trimester; T2, second trimester; T3, third trimester