Diagnostic imaging rates for head injury in the ED and states' medical malpractice tort reforms

Received 7 October 2009; received in revised form 26 January 2010; accepted 27 January 2010. published online 14 July 2010.
Corrected Proof

Abstract

Objective

Physicians' fears of being sued may lead to defensive medical practices, such as ordering nonindicated medical imaging. We investigated the association between states' medical malpractice tort reforms and neurologic imaging rates for patients seen in the emergency department with mild head trauma.

Methods

We assessed neurologic imaging among a national sample of 8588 women residing in 10 US states evaluated in an emergency setting for head injury between January 1, 1992, and December 31, 2001. We assessed the odds of imaging as it varied by the enactment of medical liability reform laws.

Results

The medical liability reform laws were significantly associated with the likelihood of imaging. States with laws that limited monetary damages (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.40-0.99), mandated periodic award payments (OR, 0.64; 95% CI, 0.43-0.97), or specified collateral source offset rules (OR, 0.62; 95% CI, 0.40-0.96) had an approximately 40% lower odds of imaging, whereas states that had laws that limited attorney's contingency fees had significantly higher odds of imaging (OR, 1.5; 95% CI, 0.99-2.4), compared to states without these laws. When we used a summation of the number of laws in place, the greater the number of laws, the lower the odds of imaging. In the multivariate analysis, after adjusting for individual and community factors, the total number of laws remained significantly associated with the odds of imaging, and the effect of the individual laws was attenuated, but not eliminated.

Conclusion

The tort reforms we examined were associated with the propensity to obtain neurologic imaging. If these results are confirmed in larger studies, tort reform might mitigate defensive medical practices.

a Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA

b Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA

c Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, CA, USA

d Department of Radiology, Massachusetts General Hospital, Harvard Medical School, USA

e Genomic Health, Redwood City, CA 94063-4700, USA

Corresponding author. Department of Radiology, University of California, San Francisco, CA, USA. Tel.: +1 415 353 4946; fax: +1 415 353 2790.

PII: S0735-6757(10)00040-9

doi:10.1016/j.ajem.2010.01.038