Clinicians Often Underestimate Harms of Tests and Treatments
Written by Editor   
Monday, February 06, 2017 11:58 AM

News Bite:  Clinicians are likely to underestimate harms and overestimate benefits of tests and treatments.  Harms are correctly estimated 13% of the time and benefits only 11%.  The moral?  The estimates of "harm" and "benefit" that you will encounter are usually NOT correct.

Clinicians are likely to underestimate harms and overestimate benefits of tests and treatments, according to the results of a review of 48 studies. Patients cannot be assisted to make informed decisions if clinicians themselves do not have accurate expectations of intervention benefits and harms. the authors note.   

The review showed that the majority of clinicians correctly estimated harms only 13% of the time, and benefits only 11% of the time. Previous studies on patient expectations show that they, too, overestimate benefits and underestimate harms of many aspects of their care.

The clinicians' estimates varied widely across specialties and treatments. For example, more than 90% overestimated hormone replacement therapy's ability to reduce the risk for hip fracture, whereas more than 90% underestimated the risk for fatal cancer from bone scans.

The systematic review aimed to evaluate studies across all disciplines where clinicians were asked to estimate the benefits or harms of any test, screening, or treatment. The outcomes and responses were too variable to be combined into a meta-analysis, so instead, the researchers calculated the percentage of clinicians who underestimated, overestimated, or answered correctly about the benefits or harms in question.

Clinicians' own biases may also include an enthusiasm for any treatment over none, or a desire for reassurance. There is also a proposed “therapeutic illusion," in which clinicians see interventions in a more positive light, especially ones they are more familiar with. One of the studies, which compared two specialties, found that clinicians were likely to think more highly of the intervention that they provided.

When the review authors looked just at medications, they found that clinicians overestimated both the benefits and the harms.