Automation of cleaning and reconstructing residential address histories to assign environmental exposures in longitudinal studies

Abstract

Background: We have developed an open-source ALgorithm for Generating Address Exposures (ALGAE) that cleans residential address records to construct address histories and assign spatially-determined exposuresto cohort participants. The first application of this algorithm was to construct prenatal and early-life air pollution exposure for individuals of the Avon Longitudinal Study of Parents and Children (ALSPAC)in the South West of Englandusingpreviously estimated particulate matter ≤10 μm (PM10) concentrations. Methods: ALSPAC recruited 14,541 pregnant women between 1991and 1992. We assignedtrimester-specific estimated PM10exposures for 12,752 pregnancies,and first year of life exposures for 12,525births, based on maternal residence and residential mobility. Results: Average PM10exposure was32.6 μg/m3(StDev. 3.0 μg/m3) during pregnancy and 31.4 μg/m3(StDev. 2.6 μg/m3) during the first year of life. 6.7% ofwomen changedaddress during pregnancy, and 18.0% moved during first year of lifeof their infant. Exposure differences ranged from -5.3 μg/m3 to 12.4 μg/m3(up to 26% difference) during pregnancy and -7.22 μg/m3to 7.64 μg/m3(up to 27% difference) in the first year of life,when comparing estimated exposure using the address at birth and that assessedusing the complete cleaned address history. For the majority of individualsexposure changed by <5% but some relatively large changes were seen both in pregnancy and infancy.Conclusion: ALGAE provides a generic andadaptable, open-source solution to clean addresses stored in acohort contact database and assign life-stage specific exposureestimates with the potential to reduce exposure misclassification.