Computer Systems To Help with Ordering Blood Tests in Primary Care

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The summary below is from the full report titled "Assessment of Decision Support for Blood Test Ordering in Primary Care. A Randomized Trial." It is in the 20 February 2001 issue of Annals of Internal Medicine(volume 134, pp 274-281). The authors are MAM van Wijk, J van der Lei, M Mosseveld, AM Bohnen, and JH van Bemmel.

What is the problem and what is known about it so far?

Many doctors use computerized medical records. Studies show that linking medical records with special electronic programs and reminders can help doctors order correct tests, medications, and procedures. It is not known, however, which type of computer system helps doctors the most in deciding which routine blood tests to order.

Why did the researchers do this particular study?

To see which of two versions of a computer-based decision support system would have the greatest effect on the number of routine blood tests ordered by doctors.

Who was studied?

The study involved 44 medical practices and 60 doctors in the Netherlands. All practices used computerized medical records. There were 155,797 patients enrolled in the practices.

How was the study done?

The researchers assigned medical practices at random to use one of two computer-based decision support systems. In the first system, medical records were linked to an electronic list of blood tests. Doctors selected orders from an initial list of 15 common blood tests or by clicking and searching for other tests. In the second system, medical records were linked electronically with summaries of official Dutch clinical guidelines that included recommendations for test ordering. The doctors looked up guidelines that applied to their particular patients and chose whether or not to order the tests that were suggested.

What did the researchers find?

During the 1-year study period, doctors who used the system linked to guidelines ordered about 20% fewer blood tests than did doctors who used the system linked to lists of tests. Doctors assigned to the guideline-linked system used this system to order 71% of their blood tests; those assigned to the list-linked system used it to order 88% of their blood tests. Doctors used paper rather than electronic forms to order remaining blood tests.

What were the limitations of the study?

The study simply counted the number of tests ordered. It did not measure which system led to the most appropriate ordering of blood tests, or to the best patient outcomes.

What are the implications of the study?

Computer programs can successfully link medical records of patients with relevant guidelines and suggestions for specific blood tests. Such systems can reduce the number of blood tests ordered by doctors.