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An actuarial investigation into maternal out-of-hospital cost risk factors

  • Jananie William (a1), Catherine Chojenta (a2), Michael A. Martin (a1) and Deborah Loxton (a2)

This paper adopts an actuarial approach to identify the risk factors of government-funded maternal out-of-hospital costs in Australia, with a focus on women who experience adverse birth outcomes. We use a two-phase modelling methodology incorporating both classification and regression trees and generalised linear models on a data set that links administrative and longitudinal survey data from a large sample of women, to address maternal out-of-hospital costs. We find that adverse births are a statistically significant risk factor of out-of-hospital costs in both the delivery and postnatal periods. Furthermore, other significant cost risk factors are in-vitro fertilisation, specialist use, general practitioner use, area of residence and mental health factors (including anxiety, intense anxiety, postnatal depression and stress about own health) and the results vary by perinatal sub-period and the patient’s private health insurance status. We highlight these differences and use the results as an evidence base to inform public policy. Mental health policy is identified as a priority area for further investigation due to the dominance of these factors in many of the fitted models.

Corresponding author
*Correspondence to: Jananie William, Research School of Finance, Actuarial Studies and Statistics, College of Business and Economics, Australian National University, Canberra, ACT 0200, Australia. Tel: +61 2 6125 7311; E-mail:
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William, J., Chojenta, C., Martin, M. & Loxton, D. (2017). An actuarial investigation into maternal hospital cost risk factors for public patients. Annals of Actuarial Science, 1–24.
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Annals of Actuarial Science
  • ISSN: 1748-4995
  • EISSN: 1748-5002
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