Fig. 1

Distribution of differences in expected probabilities of HIV screening between (a) women who received four or more and those who received three or less antenatal care visits, (b) women who were attended by a physician or a nurse and those who were not, (c) women who received four or more antenatal care visits and were attended by a physician or a nurse, and those who received less than four antenatal care visits and were not attended by a physician or a nurse, and (d) most and least educated women (MFD: Mean first difference)Note: The area under the curve, in each panel, represents the distribution of the differences between the expected probabilities of HIV testing under two scenarios for a simulated modifiable factor. The red line represents the mean of the distribution. The x-axis represents the first differences in the expected probabilities of HIV screening and is limited to the probabilities obtained from the simulated first differences. The y-axis represents the density of the probability distribution of the first differences and is limited to the maximum observed density. For example, in panel A, the interval of the simulated first differences in the expected probabilities of HIV screening between women who received four or more and those who received three or less antenatal care visits is approximately [− 0.05 to 0.10]. However, the vast majority of this interval is [0.0 to 0.50], and the mean first difference is at 0.022