Strep throat risk score brings together patient data and big data to potentially reduce unnecessary doctors' visits

A new risk measure called a "home score" could potentially prevent 230,000 trips to US doctors' offices every year for suspected strep throat, according to a study online in Annals of Internal Medicine.

The score combines patients' symptoms and demographic information with data on local strep throat activity to estimate their strep risk, empowering them to seek care appropriately. The home score is said to represent the first healthcare tool to bring patient-contributed data and public health "big data" together to assess an individual's risk for a communicable disease.

Dr Fine“Integrating real-time strep throat biosurveillance with 2 patient-reported symptoms can accurately identify low-risk patients who are unlikely to even be tested for strep throat,” said lead study author Andrew M. Fine, MD, MPH, pediatric emergency medicine, Boston Children's Hospital. “This approach could save hundreds of thousands of visits annually for patients with pharyngitis.”

Currently physicians use an office-based tool that takes into account symptoms and physical examination results to determine a person's risk for strep throat. If the risk is low, guidelines recommend against testing or treating the patient.

Dr Fine and colleagues used information collected between September 2006 and December 2008 from 71,776 people over aged 15 years who visited CVS MinuteClinics in 6 states for sore throats. They used patient’s medical records and strep test results to test a tool that calculated a home score. Patients without medical training can assign themselves a score based on 2 symptoms-fever and cough. The tool also takes into account how common strep throat has been in the person's community during the past 2 weeks before calculating the home score.

Based on the recent, local epidemiology of strep throat and 2 simple symptoms (fever, cough), the home score can be calculated to provide a patient’s risk of strep, on a scale of 0-100. In this study, a patient with a home score of less than 10 was considered at low risk for strep throat. The researchers found that 90% of patients who scored below 10 on the at-home tool would have tested negative for strep throat. According to Dr Fine, there would be 27 fewer doctors' visits for every 1 person with strep throat who was missed by the tool.

“Bringing local, recent epidemiology into the medical decision making process is something that can be achieved on the local level,” said Dr Fine, assistant professor of pediatrics, Harvard Medical School. “Our study provides an early example of how to apply local epidemiology to individual patients. This study shows how valuable it can be to have quantitative information about the local incidence of disease. This is especially important for a communicable disease like strep throat.

“Once validated prospectively, any health system that tests patients for strep throat, could use the local epidemiology to help drive the decision about whether patients need to be seen right away, or whether they can wait to see if they get better on their own,” he concluded.