Risk-adjusted operative delivery rates and maternal-neonatal outcomes as measures of quality assessment in obstetric care: a multicenter prospective study.
BACKGROUND
Although the evaluation of caesarean delivery rates has been suggested as one of the most important indicators of quality in obstetrics, it has been criticized because of its controversial ability to capture maternal and neonatal outcomes. In an "ideal" process of labor and delivery auditing, both caesarean (CD) and assisted vaginal delivery (AVD) rates should be considered because both of them may be associated with an increased risk of complications. The aim of our study was to evaluate maternal and neonatal outcomes according to the outlier status for case-mix adjusted CD and AVD rates in the same obstetric population.


METHODS
Standardized data on 15,189 deliveries from 11 centers were prospectively collected. Multiple logistic regression was used to estimate the risk-adjusted probability of a woman in each center having an AVD or a CD. Centers were classified as "above", "below", or "within" the expected rates by considering the observed-to-expected rates and the 95% confidence interval around the ratio. Adjusted maternal and neonatal outcomes were compared among the three groupings.


RESULTS
Centers classified as "above" or "below" the expected CD rates had, in both cases, higher adjusted incidence of composite maternal (2.97%, 4.69%, 3.90% for "within", "above" and "below", respectively; p = 0.000) and neonatal complications (3.85%, 9.66%, 6.29% for "within", "above" and "below", respectively; p = 0.000) than centers "within" CD expected rates. Centers with AVD rates above and below the expected showed poorer and better composite maternal (3.96%, 4.61%, 2.97% for "within", "above" and "below", respectively; p = 0.000) and neonatal (6.52%, 9.77%, 3.52% for "within", "above" and "below", respectively; p = 0.000) outcomes respectively than centers with "within" AVD rates.


CONCLUSIONS
Both risk-adjusted CD and AVD delivery rates should be considered to assess the level of obstetric care. In this context, both higher and lower-than-expected rates of CD and "above" AVD rates are significantly associated with increased risk of complications, whereas the "below" status for AVD showed a "protective" effect on maternal and neonatal outcomes.
Department of Obstetrics and Gynecology, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Via dell'Istria 65/1, Trieste, 34137, Italy. gianpaolo.maso@burlo.trieste.it.
Gianpaolo
G
Maso
Epidemiology and Biostatistics Unit, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Trieste, Italy. lorenzo.monasta@burlo.trieste.it.
Lorenzo
L
Monasta
Department of Obstetrics and Gynecology, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Via dell'Istria 65/1, Trieste, 34137, Italy. picciuli72@gmail.com.
Monica
M
Piccoli
Epidemiology and Biostatistics Unit, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Trieste, Italy. luca.ronfani@burlo.trieste.it.
Luca
L
Ronfani
Epidemiology and Biostatistics Unit, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Trieste, Italy. marcella.montico@burlo.trieste.it.
Marcella
M
Montico
Department of Obstetrics and Gynecology, Institute for Maternal and Child Health - IRCCS Burlo Garofolo and Department of Medical Sciences, University of Trieste, Trieste, Italy. fradeseta@gmail.com.
Francesco
F
De Seta
Department of Obstetrics and Gynecology, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Via dell'Istria 65/1, Trieste, 34137, Italy. parolinsara@gmail.com.
Sara
S
Parolin
Department of Obstetrics and Gynecology, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Via dell'Istria 65/1, Trieste, 34137, Italy. catebusinelli@gmail.com.
Caterina
C
Businelli
Department of Neonatology and Neonatal Intensive Care, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Trieste, Italy. laura.travan@burlo.trieste.it.
Laura
L
Travan
Department of Obstetrics and Gynecology, Institute for Maternal and Child Health - IRCCS Burlo Garofolo, Via dell'Istria 65/1, Trieste, 34137, Italy. salvatore.alberico@burlo.trieste.it.
Salvatore
S
Alberico
D036861:Delivery, Obstetric / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D007744:Obstetric Labor Complications / Q000453:epidemiology / Q000517:prevention & control; D009774:Obstetrics / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D011446:Prospective Studies; D011785:Quality Assurance, Health Care / Q000379:methods / Q000458:organization & administration; D058996:Quality Improvement; D018570:Risk Assessment