You are here: Value of Medical Imaging

  • June 2009

    The Association Between Hospital Outcomes & Diagnostic Imaging: Could More Be Better?

    Academy Health 2009 Annual Research Meeting | David W. Lee, Ph.D. and David A. Foster, Ph.D.


    David W. Lee, Ph.D. and David A. Foster, Ph.D.


    Academy Health 2009 Annual Research Meeting, June 29, 2009


    Diagnostic imaging, such as computed tomography (CT), magnetic radiology (MR), ultrasound and x-ray, uses advanced radiation technology to view the inside of a patient’s body for signs of stroke, cancer and other serious diseases. Though the significant medical benefits of such technologies have been well documented and established, there continues to be debate over how often to use diagnostic imaging as total U.S. healthcare system costs continue to soar.

    In order to test whether the “more is better” hypothesis holds for diagnostic imaging, researchers examined the association between the use of inpatient diagnostic imaging services (CT, MR, ultrasound and x-ray) and three risk-adjusted hospital outcome measures: mortality, length of stay and total inpatient hospital costs. Researchers used patient-level data to determine whether the patient received imaging services, and the mean number of services received. The study examined 2007 data from the Thomson Reuters Hospital Drug Database for 1.1 million patients treated at 102 hospitals, ranging from hospitals with fewer than 200 beds to those with more than 500 beds, and with the majority of hospitals surveyed located in the Southern region of the U.S.


    The study findings suggest that the increased use of imaging services is associated with lower patient mortality while at the same time having little or no impact on length of stay or costs. The risk-adjusted probability of receiving an imaging service had an inverse and statistically significant correlation with risk-adjusted mortality for all four imaging modalities, ranging from -0.20 (MR) to -0.24 (ultrasound). This means that as use of imaging increased, patient mortality decreased.

    While utilization of imaging services was positively correlated with costs and length of stay, none of the correlations between imaging and costs achieved statistical significance. Associations between imaging utilization and length of stay were statistically significant only for the likelihood of receiving any ultrasound, the number of ultrasounds received and the number of x-ray services received.


    Because providers are only reimbursed for the professional component of inpatient diagnostic services, use of these services likely reflects a confidence in their clinical value. This study highlights the need for further assessment of how diagnostic imaging shapes key clinical, operational and economic outcomes in the inpatient setting, particularly as discussions about its appropriate utilization continue.

    Click here to access more information (Page 331).

Connect with Us Online

  • Twitter
  • Facebook
  • YouTube
  • Flickr