Using hospital records for creating birth cohorts

Linkage between routinely collected hospital birth and other records offers the potential for epidemiological and public health research by developing population-level birth cohorts with lifelong follow-up. In a paper published in the Journal of Public Health, Jo Murray and colleagues from Imperial College London examined the range and completeness of birth information recorded in Hospital Episode Statistics (HES) and tested an approach for minimizing the effect of hospital-level variations by selecting hospitals with high completeness of recording (≥90%) for key fields. The authors reported that the proportion of missing data in key birth record fields such as gestational age and birth weight has been decreasing annually (from 46.2 and 43.9% in 2005/06 to 18.1 and 16.9% in 2009/10, respectively). There was however a wide variation in the completeness of recording between hospitals. The authors concluded that the completeness of recording of hospital birth information varies greatly between hospitals in England but is improving; and that it may be preferable to construct cohorts from only hospitals with high completeness of recording.