Nearly half of COVID-19 resident deaths and cases that happened before the federal reporting requirement started were not included in provider data submitted to the federal government, according to a new study by Harvard researchers. 

The missed data represented 11.6% of total COVID-19 cases and 14% of total deaths among nursing home residents in 2020.  

“This has made it very difficult to get an accurate picture of the total impact of COVID on nursing homes, especially for facilities in Northeast states that experienced early outbreaks in the spring of 2020,” said co-author David Grabowski, Ph.D.

The study was published Thursday in JAMA Network Open. Researchers used state data to estimate the total number of nursing home cases and deaths for 2020 for the study. 

The Centers for Medicare & Medicaid Services in April 2020 first announced that nursing homes would be required to report COVID-19 infections directly to the Centers for Disease Control and Prevention through the National Healthcare Safety Network. In May, the agency updated the requirement to include COVID-related deaths.

Approximately 44% of nursing home cases and 40% of deaths that occurred before the start of reporting were not included in the first submissions, according to the study. 

Findings also found that more than 16,000 COVID-19 deaths and 68,000 cases among nursing home residents nationwide were omitted from federal data when the data submission was optional.  

The omissions resulted in severe underreporting by the NHSN and could have impacted the federal government response to providers most in need during the first months of the pandemic. 

“It stresses the importance of requiring reporting as soon as possible and trying to maintain high data quality standards,” co-author Karen Shen, Ph.D., told McKnight’s Long-Term Care News Wednesday. “That just really complicated knowing what was going on early in the pandemic, and I think that probably delayed any reactions or mirroring policies that would have been helpful.”

Investigators now estimate the national 2020 total of nursing home COVID cases was 592,629, and the COVID death count was 118,335 after adding the unreported cases and deaths to the year’s  totals. 

“We kind of knew what was happening. If you look at total deaths, we know that they were super high early in the pandemic,” Shen added. “If you looked at the numbers from the NHSN, I think most people knew that they were wrong, but it’s just kind of important to quantify them.”