Key Insights

• A recent study by the JAMA Network found that ICD-10 codes are not accurately capturing COVID-19 symptoms, allowing room for false negatives.
• Currently, it is unknown just how accurate ICD-10 characterizations are for the COVID-19 disease.
• The study warns that this inaccurate classification can have a negative impact on downstream research and surveillance that relies on the ICD-10 codes.

The Rundown

In March 2020, the World Health Organization (WHO) released emergency ICD-10 coding requirements for COVID-19, which included specific requirements physicians and providers must follow in order to accurately classify the disease and patients’ symptoms. The Centers for Disease Control and Prevention (CDC) outlined additional guidance regarding COVID-19-related symptoms or potential COVID-19-related symptoms, including acute bronchitis, lower respiratory infection, pneumonia, and acute respiratory distress syndrome. Other symptoms, such as shortness of breath, also known as dyspnea, are included as separate categories.

The Study

In a study published by the JAMA Network, researchers from the University of Utah School of Medicine and the University of Utah Health Sciences Center in Salt Lake City have identified troubling inaccuracies concerning ICD-10 coding for COVID-19-related symptoms. 

Researchers aggregated and reviewed electronic medical records of “2,201 patients tested for COVID-19 between March 10 and April 6, 2020” for accurate reporting of COVID-19 symptoms like “fever, cough, and dyspnea.” In this cohort study, “the mean (SD) age was 42 (17) years; 1201 (55%) of participants were female, 1569 (71%) were White, and 282 (13%) were Hispanic or Latino.” Sixty-six percent of patients exhibited fever, 88 percent of patients exhibited a cough, and 64 percent of patients had dyspnea, all of which are common COVID-19-related symptoms.

The Findings

After evaluating the medical records, researchers found that “symptom-specific ICD-10 codes lack sensitivity and fail to capture many patients with relevant symptoms; the false-negative rate is unacceptably high.” The net predictive value (NPR) “was poor for all symptoms, with 0.33 for fever, 0.12 for cough, and 0.30 for dyspnea.” In fact, false-negative ICD-10 code ranged “from 35.8 percent for fever among patients older than 64 years to 54.5 percent for fever among patients who tested positive for SARS-CoV-2 infection.”

What This May Mean for Physicians

False negatives can lead to higher mortality and morbidity rates. Researchers note that apart from ICD-10 code sensitivity, “clinicians may not document symptoms for all patients, particularly when patient volume is high or in drive-through testing scenarios.” In these cases, it may be beneficial for clinicians to reserve a few extra minutes of time with patients who have reported COVID-19-related symptoms.

Although inaccurate ICD-10 coding may present significant difficulty with retrospective research of the COVID-19 virus, there is a silver lining. The researchers have noted that there are alternative measures to help catch more positive cases, such as creating a standardized symptom checker and relying more on patient-reported data, which “may allow more reliable symptom capture, without reliance on billing codes or clinician documentation.” 

Several companies are creating mobile apps to help patients report COVID-19 symptoms as well as potential exposure to the appropriate health authorities. Virginia is the first state to launch a COVID-19 notification app, called COVIDWISE, to help notify individuals of possible COVID exposure. Such apps may provide highly beneficial data for providers and public health authorities in the near future.