Using troves of data to allow patients to know whether they are at risk for strep throat, Harvard Medical School researchers hope to lessen the number of unnecessary visits Americans make to their doctors for strep tests.

Kenneth D. Mandl and Andrew M. Fine ’91 of the Medical School and of Boston Children’s Hospital and Victor Nizet of the School of Pharmacy at the University of California, San Diego have created a “strep scorecard” for patients to use at home before going to the doctor for a test.

Developed to be an application on a phone or computer, the strep scorecard would ask two questions: whether the patient has a fever, which correlates with strep, and a cough, which correlates with a viral infection that does not require medical attention.

“To date, big data are not used to inform clinical decision-making, and relying on patients to accurately report information is only an emerging science,” Mandl said.

The scorecard would supply the patient with their risk of strep throat based on their two reported symptoms and the data on strep throat cases in clinics in the patient’s region. It then recommends that the patient go to the doctor or instead wait a few days.

Fine clarified that the algorithm in the scorecard does not diagnose strep, but only determines the patient’s risk for strep.

“Since most throat infections are viral and go away within a few days, the scorecard allows patients to avoid an immediate visit to the doctor,” Fine said.

The researchers found 8,500 patients each year would receive antibiotics but not be treated properly. Fine noted that current strep tests are not perfect anyway and that doctors already do not do a strep test on a patient with a low risk for the disease.

In their initial work on the project, published in the Annals of Internal Medicine earlier this month, Fine and Mandl used the medical records of 71,776 patients who received strep tests at CVS MinuteClinics from 2006 to 2008. They used the scorecard method from the patients’ records and compared it to the strep test results.

The researchers concluded that the likelihood of strep throat was less than 10 percent among the patients, who were each 15 years of age or older. They estimated that if patients managed their symptoms with this application, 230,000 visits in the United States could be avoided each year.

“The momentum in healthcare today is to save the cost of the total patient and minimize unnecessary visits and procedures to keep populations healthy and costs low,” Mandl said.

Both the cost of making laboratory data on strep throat cases publically available and creating an application are inexpensive approaches to keep unnecessary visits to a minimum, increasing the efficiency of cash-strapped clinics.

“The scorecard brings two innovative approaches together to enable something unique in modern medicine,” Mandl said.