The hypothesis of the study -- based on earlier predictions by health policy experts -- was that if physicians had online access to results of tests recently ordered by other doctors, they wouldn't order those tests again for the same patients. If that proved to be true, according to the hypothesis, there should be some cost savings.
The researchers measured the test ordering rates and the associated costs in Mesa County, Colo. from 2005, when Quality Health Network (QHN) launched an HIE in the area, to 2010. In the latter year, 85% of local practices were participating in the HIE, the paper said.
Using claims data from Rocky Mountain Health Plans, the dominant health plan in the market, the researchers compared the test ordering rates of 306 providers in 69 practices before and after they joined the HIE. For both primary care providers and specialists, the rate of lab testing increased over the five-year period but dropped significantly after their practices joined the HIE. The rates of imaging test orders remained more or less constant over the time period and were not affected by HIE.
[ ONC has released resources to help providers prepare for information exchange. Read more at ONC Steps Up MU Stage 2 Preparation. ]
The total costs of the lab tests did not drop significantly after the practices joined QHN. The average cost per test did not change much, either, which raises the question of why overall costs did not drop with ordering rates. The researchers explained that they used different methods to analyze costs and testing rates to reduce the skewing effect of a few very expensive imaging tests. But in any case, it doesn't appear that the availability of the test results through the HIE had much effect on costs.
In an interview with InformationWeek Healthcare, lead author Steve Ross, MD, associate clinical professor at the University of Colorado School of Medicine, said that the percentage of practices that were involved in QHN didn't reach critical mass until around 2008. He pointed out that there's a network effect in the use of HIE data that is related to the adoption of the exchange. "The more people are on it, the more value it's going to have," he said, and the more likely providers are to use it.
However, Ross noted, HIE participants had access to test results from some physicians who did not belong to QHN. That is because the bulk of the tests were done at one of the two area hospitals, which used QHN to deliver lab results electronically to staff physicians. All of their results went to the HIE, although only those who were online with the exchange could receive them in their EHR. Physicians who used the HIE to look up results on tests ordered by other physicians could therefore find any that were performed by the hospitals, even if the doctors who ordered the tests did not participate in QHN.
A more important caveat to the study results is that physicians are generally reluctant to leave their workflow to look up clinical data from other practitioners on a website. According to Ross, if the providers in the JAMIA study had been able to look up community test results on their patients without leaving their EHR, it's very possible that the HIE would have proved its effectiveness further.
The study's data was insufficient to distinguish the extent to which physicians were using the HIE merely to receive test results or were going on the QHN site to look up outside information, Ross said. But, he pointed out, "[The latter] is where you're really going to see the benefit -- where you have access to something you wouldn't have had access to otherwise."
Another recent study found that physicians' access to computerized imaging results (sometimes, but not necessarily, through an electronic health record) was associated with a 40%-70% greater likelihood of an imaging test being ordered. The study's authors speculated that electronic access does not decrease test ordering in the office setting may even increase it, possibly because of system features that are enticements to ordering.