Understanding patterns in maternity care in the NHS and getting it right

This week, the Royal College of Obstetricians and Gynaecologists published its report on patterns of maternity care in English NHS hospitals during 2011 to 2012.1 The stated aim was to “examine the validity of potential performance indicators, and to determine how successfully these could be used to compare performance between maternity units using available data.” Data from inpatient admissions and day cases collected routinely from English NHS trusts through Hospital Episode Statistics (HES) were analysed to provide an initial 11 performance indicators, all related to intrapartum care (box). The report presents the data as risk adjusted estimates for each maternity unit within a funnel plot showing the national mean. If variation occurred at random, only one in 20 or one in 500 units would be expected to lie outside the limits representing two (inner funnel limits) or three (outer limits) standard deviations, respectively.