Sex ratio at birth estimation and projection for Pakistan provinces, a Bayesian modeling approach
Pakistan is a country with strong preference of boys to girls. Previous evidence on the sex preference is mainly reported at the postnatal stage where the child mortality among females is higher than that among the males. Gender discrimination in Pakistan at the prenatal stage, reflected in the inflated sex ratio at birth (SRB; defined as the ratio of male to female births) has been barely mentioned before.
We aim to estimate the SRB and missing female births by Pakistan province from 1980 and 2018 and identify provinces with imbalanced SRB. We compiled an extensive SRB database from all available surveys and censuses which consists 740,602 birth records. We adopt a Bayesian hierarchical time series model to synthesize different data sources and provide annual estimates and associated uncertainty of SRB across provinces. Our model identifies Balochistan to have SRB imbalance since 1980, with the maximum SRB estimated to occur in 1997 at 1.121 with 95% credible interval [1.066; 1.142].