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International Journal of Health Economics and Management

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Open Access 01-03-2017 | Research Article

Economic incentives and diagnostic coding in a public health care system

Authors: Kjartan Sarheim Anthun, Johan Håkon Bjørngaard, Jon Magnussen

Published in: International Journal of Health Economics and Management | Issue 1/2017

Abstract

We analysed the association between economic incentives and diagnostic coding practice in the Norwegian public health care system. Data included 3,180,578 hospital discharges in Norway covering the period 1999–2008. For reimbursement purposes, all discharges are grouped in diagnosis-related groups (DRGs). We examined pairs of DRGs where the addition of one or more specific diagnoses places the patient in a complicated rather than an uncomplicated group, yielding higher reimbursement. The economic incentive was measured as the potential gain in income by coding a patient as complicated, and we analysed the association between this gain and the share of complicated discharges within the DRG pairs. Using multilevel linear regression modelling, we estimated both differences between hospitals for each DRG pair and changes within hospitals for each DRG pair over time. Over the whole period, a one-DRG-point difference in price was associated with an increased share of complicated discharges of 14.2 (95 % confidence interval [CI] 11.2–17.2) percentage points. However, a one-DRG-point change in prices between years was only associated with a 0.4 (95 % CI \(-1.1\) to 1.8) percentage point change of discharges into the most complicated diagnostic category. Although there was a strong increase in complicated discharges over time, this was not as closely related to price changes as expected.

In 1999–2001, the share of income related to activity was 50 %, increasing to 55 % in 2002 and 60 % in 2003. The share fell to 40 % in 2004, and rose again to 60 % in 2005. The share returned to 40 % in the years 2006–2008.

The Norwegian Patient Register is a complete registry of all specialized hospital care. The interpretation and reporting of these data are the sole responsibility of the authors, and no endorsement by the Norwegian Patient Register is intended nor should be inferred.

These five excluded DRGs were 372/373 (Vaginal births), 76/77 (Other respiratory operating room procedures), 452A/453A (Complications of treatment with surgery), 454/455 (Other injury, poisoning & toxic effect) and 478/479 (Other vascular procedures). Among these DRG pairs, vaginal births was the largest of all complicated/uncomplicated pairs, and was excluded due to significant alterations in the specifications of the DRG pair during the period.

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Title: Economic incentives and diagnostic coding in a public health care system
Authors: Kjartan Sarheim Anthun
Johan Håkon Bjørngaard
Jon Magnussen
Publication date: 01-03-2017
Publisher: Springer US
Published in: International Journal of Health Economics and Management / Issue 1/2017
Print ISSN: 2199-9023
Electronic ISSN: 2199-9031
DOI: https://doi.org/10.1007/s10754-016-9201-9

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