title: Routinely collected English birth data sets: comparisons and recommendations for reproductive epidemiology.
abstract: BACKGROUND
  In England there are four national routinely collected data sets on births: Office for National Statistics (ONS) births based on birth registrations; Hospital Episode Statistics (HES) deliveries (mothers' information); HES births (babies' information); and NHS Numbers for Babies (NN4B) based on ONS births plus gestational age and ethnicity information. This study describes and compares these data, with the aim of recommending the most appropriate data set(s) for use in epidemiological research and surveillance.
  
  
  METHODS
  We assessed the completeness and quality of the data sets in relation to use in epidemiological research and surveillance and produced detailed descriptive statistics on common reproductive outcomes for each data set including temporal and spatial trends.
  
  
  RESULTS
  ONS births is a high quality complete data set but lacks interpretive and clinical information. HES deliveries showed good agreement with ONS births but HES births showed larger amounts of missing or unavailable data. Both HES data sets had improved quality from 2003 onwards, but showed some local spatial variability. NN4B showed excellent agreement with ONS and HES deliveries for the years available (2006-2010). Annual number of births increased by 17.6% comparing 2002 with 2010 (ONS births). Approximately 6% of births were of low birth weight (2.6% term low birth weight) and 0.5% were stillbirths.
  
  
  CONCLUSIONS
  Routinely collected data on births provide a valuable resource for researchers. ONS and NN4B offer the most complete and accurate record of births. Where more detailed clinical information is required, HES deliveries offers a high quality data set that captures the majority of English births.
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK.
authors.forename: Rebecca E
authors.initials: RE
authors.lastname: Ghosh
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK.
authors.forename: Danielle C
authors.initials: DC
authors.lastname: Ashworth
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK Imperial College Healthcare NHS Trust, London, UK.
authors.forename: Anna L
authors.initials: AL
authors.lastname: Hansell
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK.
authors.forename: Kevin
authors.initials: K
authors.lastname: Garwood
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK Imperial College Healthcare NHS Trust, London, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK.
authors.forename: Mireille B
authors.initials: MB
authors.lastname: Toledano
mesh_terms: D001723:Birth Rate / Q000639:trends; D066264:Datasets as Topic / Q000592:standards*; D004739:England / Q000453:epidemiology; D062665:Epidemiological Monitoring; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D060728:Reproductive Health / Q000706:statistics & numerical data*; D050497:Stillbirth
keywords: Data Collection; Epidemiology; Statistics