{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T14:51:48Z","timestamp":1790088708528,"version":"4.0.1"},"reference-count":43,"publisher":"BMJ","issue":"9","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2015,8,4]]},"published-print":{"date-parts":[[2015,9]]},"abstract":"<jats:sec><jats:title>Objectives<\/jats:title><jats:p>To examine interhospital variation in rates of induction of labour (IOL) to identify potential targets to reduce high rates of practice variation.<\/jats:p><\/jats:sec><jats:sec><jats:title>Design<\/jats:title><jats:p>Population-based record linkage cohort study.<\/jats:p><\/jats:sec><jats:sec><jats:title>Setting<\/jats:title><jats:p>New South Wales, Australia, 2010\u20132011.<\/jats:p><\/jats:sec><jats:sec><jats:title>Participants<\/jats:title><jats:p>All women with live births of \u226524\u2005weeks gestation in 72 hospitals.<\/jats:p><\/jats:sec><jats:sec><jats:title>Primary outcome measure<\/jats:title><jats:p>Variation in hospital IOL rates adjusted for differences in case-mix, according to 10 mutually exclusive groups derived from the Robson caesarean section classification; groups were categorised by parity, plurality, fetal presentation, prior caesarean section and gestational age.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The overall IOL rate was 26.7% (46\u2005922 of 175\u2005444 maternities were induced), ranging from 9.7% to 41.2% (IQR 21.8\u201329.8%) between hospitals. Nulliparous and multiparous women at 39\u201340\u2005weeks gestation with a singleton cephalic birth were the greatest contributors to the overall IOL rate (23.5% and 20.2% of all IOL respectively), and had persisting high unexplained variation after adjustment for case-mix (adjusted hospital IOL rates ranging from 11.8% to 44.9% and 7.1% to 40.5%, respectively). In contrast, there was little variation in interhospital IOL rates among multiparous women with a singleton cephalic birth at \u226541\u2005weeks gestation, women with singleton non-cephalic pregnancies and women with multifetal pregnancies.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>7 of the 10 groups showed high or moderate unexplained variation in interhospital IOL rates, most pronounced for women at 39\u201340\u2005weeks gestation with a singleton cephalic birth. Outcomes associated with divergent practice require determination, which may guide strategies to reduce practice variation.<\/jats:p><\/jats:sec>","DOI":"10.1136\/bmjopen-2015-008755","type":"journal-article","created":{"date-parts":[[2015,9,3]],"date-time":"2015-09-03T02:03:59Z","timestamp":1441245839000},"page":"e008755","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":30,"title":["Variation in hospital rates of induction of labour: a population-based record linkage study"],"prefix":"10.1136","volume":"5","author":[{"given":"Tanya A","family":"Nippita","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judy A","family":"Trevena","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jillian A","family":"Patterson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jane B","family":"Ford","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan M","family":"Morris","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine L","family":"Roberts","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2015,9,2]]},"reference":[{"key":"2024051514270985000_5.9.e008755.1","doi-asserted-by":"publisher","DOI":"10.1111\/birt.12002"},{"key":"2024051514270985000_5.9.e008755.2","doi-asserted-by":"publisher","DOI":"10.1016\/j.healthpol.2013.08.002"},{"key":"2024051514270985000_5.9.e008755.3","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.c3965"},{"key":"2024051514270985000_5.9.e008755.4","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.d1513"},{"key":"2024051514270985000_5.9.e008755.5","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.f3668"},{"key":"2024051514270985000_5.9.e008755.6","unstructured":"Li Z , Zeki R , Hilder L , et al . 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