Data dictionary for:  	heel_estimates.csv (Bangladesh heel prick results)
			cord_estimates.csv (Bangladesh cord sample results)


gest_wk	-completed weeks of gestation, derived by rounding down gestage (for classification of predictions)
gestage	-true gestational age (dating ultrasound)
pred_baseline_model -gestational age estimate from model with sex, multiple birth, birthweight
pred_analytes_model -gestational age estimate from model with sex, multiple birth, screening analytes 
pred_full_model -gestational age estimate from model with sex, multiple birth, screening analytes and birthweight