RESUMO
OBJECTIVE: To use cumulative sum (CUSUM) charts for the early detection of variations in quality of care in a maternity department. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Maternity department of a teaching hospital in Paris (France). POPULATION: Data from 20 519 women and 21 448 infants were collected between January 2000 and December 2007. METHODS: CUSUM charts were used to monitor the rate of 19 pre-selected quality indicators over 3 years (2005-2007), against standards developed by department obstetrician gynaecologists. Periods with adverse event rates that did not meet the standards were identified. MAIN OUTCOME MEASURES: Quality indicator rates. RESULTS: Indicators fell into three groups based on the number of periods with unacceptable rates: less than one per year [e.g. the rate of intensive care unit (ICU) admission of mothers and rate of third- or fourth-degree perineal tears]; one every 2-12 months on average (e.g. blood transfusion and sulprostone use in the overall population of women); and at least one per month (insufficient availability of epidural analgesia). CONCLUSION: CUSUM charts for a broad range of quality indicators can be used to monitor the quality of care in an obstetrics department. A prospective study investigating the ability of CUSUM-based monitoring to improve maternal and neonatal outcomes would be of interest.