Statistical Methods for Health Actuaries–IBNR Estimates: An Introduction

Research Projects – Health


The Health Section Research Team is pleased to make available the first in a series of guides on the use of statistical techniques that are geared toward the work of a practicing health actuary.

The first guide in the series deals with the calculation of incurred but not reported (IBNR) health claim reserves and specifically the development of confidence intervals around IBNR estimates. The guide was co–authored by Jinadasa Gamage, Jed Linfield, Krzysztof Ostaszewski and Steven Siegel.

Along with the guide below two Excel workbooks were created to demonstrate the techniques discussed in the guide.


Statistical Methods for Health Actuaries - IBNR Estimates: An Introduction

Statistical Tools–Regression Method–Workbook

Simulation Example

Thank You

The Health Section would like to thank the following members of the Project Oversight Group for their help and support of the project:

  • Rowen Bell
  • David Dickson
  • Doug Fearrington
  • Chuck Fuhrer
  • Eric Smithback
  • Tony Wittman
  • Kurt Wrobel
  • Steve Siegel, SOA Research Actuary

Special thanks to Claire Bilodeau, Elaine Canlas, Walter James, Stuart Klugman, and Jim Mange for their review and comments on the guide.

Questions Or Comments?

If you have comments or questions, please send an email to

Disclaimer for Software Posted on Web site

Important: The Statistical Tools Regression Method and Simulation Example Workbooks ("Software") posted on this site are the property of the Society of Actuaries ("SOA") and is protected under U.S. and international copyright laws. They were created for the SOA by Jinadasa Gamage, Jed Linfield, Krzysztof Ostaszewski and Steven Siegel.

The Software has been developed for the benefit of actuaries FOR EDUCATIONAL USE ONLY, although others may find it useful. SOA makes the Software available to individual users for their personal use on a non–exclusive basis. No commercial use, reproduction or distribution is permitted whatsoever.

SOA and the authors make no warranty, guarantee, or representation, either expressed or implied, regarding the Software, including its quality, accuracy, reliability, or suitability, and HEREBY DISCLAIM ANY WARRANTY REGARDING THE SOFTWARE'S MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. SOA and the authors make no warranty that the Software is free from errors, defects, worms, viruses or other elements or codes that manifest contaminating or destructive properties. In no event shall SOA or the authors be liable for any damages (including any lost profits, lost savings, or direct, indirect, incidental, consequential or other damages) in connection with or resulting from the use, misuse, reliance on, or performance of any aspect of the Software including any instructions or documentation accompanying the Software. SOA and the authors make no representation or warranty of non–infringement of proprietary rights of others with respect to the Software. The entire risk as to the uses, outputs, analyses, results and performance of the Software is assumed by the user. This Disclaimer applies regardless of whether the Software is used alone or with other software.