Developing a national birth cohort using Hospital Episode Statistics

Project and repository description

We developed a national birth cohort covering all singleton live births using Hospital Episode Statistics data. This repository covers methods for developing birth cohorts in Hospital Episode Statistics:

• Do-file 1) provide basic data cleaning for variables of interest in HES.
• Do file 2) provides additional data cleaning and code for linking them into admissions using algorithm developed by Dr Pia Hardelid.
• Do-file 3) provides basic data cleaning for variables of interest in ONS mortality records and our proposed approach to define implausible links between between HES and ONS.
• Do-files 4) and 5) provide methods for derivation of a birth cohort for singleton live births in Hospital Episode Statistics.

In brief, we used all HES episodes with an age at admission <7 days and applied broad selection criteria based on diagnostic and procedure codes, healthcare resource group codes and administrative variables recorded in HES (such as admission method or level of provided neonatal care) to identify birth episodes. We then excluded multiple births, stillbirths, episodes marked as terminations of pregnancy, unfinshed episodes, likely false matches etc.

Data sources

We used Hospital Episode Statistics, a national database covering details of all patient care in NHS funded hospitals. To find out more about Hospital Episode Statistics see:

• NHS Digital website: https://digital.nhs.uk/data-and-information/data-tools-and-services/data-services/hospital-episode-statistics
• Annie Herbert, Linda Wijlaars, Ania Zylbersztejn, David Cromwell, Pia Hardelid, Data Resource Profile: Hospital Episode Statistics Admitted Patient Care (HES APC), International Journal of Epidemiology, Volume 46, Issue 4, August 2017, Pages 1093–1093i, https://doi.org/10.1093/ije/dyx015

Software

This code was developed using Stata

Useful references for work on developing birth cohorts using HES

• Zylbersztejn A, Gilbert R, Hjern A, Wijlaars L, Hardelid P. Child mortality in England compared with Sweden: a birth cohort study. Lancet 2018;391:2008–18. https://doi.org/10.1016/s0140-6736(18)30670-6
• Harron K , Gilbert R, Cromwell D, van der Meulen J. Linking data for mothers and babies in de-identified electronic health data. PLoS One2016;11:e0164667.
• Royal College of Obstetricians and Gynaecologists. Patterns of Maternity Care in English NHS Hospitals 2011/12. London: RCOG Press; 2013. https://www.rcog.org.uk/globalassets/documents/guidelines/research--audit/patterns-of-maternity-care-in-english-nhs-hospitals-2011-12_0.pdf

Selected UCL-CHIG studies which used HES-ONS birth cohort:

• Verfürden M & Fitzpatrick T (joint first authors), Holder L, Zylbersztejn A, Rosella L, Gilbert R, Guttmann A, Hardelid P. Deprivation and pediatric respiratory tract infection mortality: a cohort study in three high-income jurisdictions. CMAJ Open (in press)
• Zylbersztejn A & Verfürden M (joint first authors), Hardelid P, Gilbert R, Wijlaars L. Phenotyping congenital anomalies in administrative hospital records. Paediatr Perinat Epidemiol. 2019;00:1–10. https://doi.org/10.1111/ppe.12627 (in press)
• Zylbersztejn A, Gilbert R, Hjern A, Hardelid P. Origins of disparities in preventable child mortality in England and Sweden: a birth cohort study. Archives of Disease in Childhood. Published Online First: 26 June 2019. https://doi.org/10.1136/archdischild-2018-316693
• Moore HC, de Klerk N, Blyth CC, Gilbert R, Fathima P, Zylbersztejn A, Verfürden M, Hardelid P. Temporal trends and socioeconomic differences in acute respiratory infection hospitalisations in children: an intercountry comparison of birth cohort studies in Western Australia, England and Scotland. BMJ Open 2019; 9, e028710. https://doi.org/10.1136/bmjopen-2018-028710

Authors

Ania Zylbersztejn - github twitter Pia Hardelid - github twitter

Acknowledgments:

Katie Harron - github twitter Linda Wijlaars - github twitter