The Iowa Department of Public Health has been misreporting COVID-19 test data for months due to a problem in its data management system. The error in the system has caused thousands of positive test results to be incorrectly backdated and reported as happening months earlier, according to a review of data published by IDPH.
This has resulted in the number of recent positive cases and the daily positivity rate for tests published by IDPH to be significantly lower than they should be, if the numbers were being reported accurately.
Rob Ramaekers, the lead epidemiologist in the IDPH Surveillance Unit, acknowledged the problem in an Aug. 14 email to Dana Jones, an Iowa City nurse practitioner, who has been independently monitoring and reviewing the data published on the IDPH COVID-19 information site.
Once a person is tested, the reporting system assigns all subsequent test results to the date of the first test, Ramaekers told Jones.
“So if I tested negative in March and was reported to IDPH, I would have a ‘Reported to IDPH’ date of March,” Ramaekers explained. “If I was tested again today and came back positive, my ‘Reported to IDPH’ date does not change and now suddenly I appear on the graph in March [instead of having the positive result assigned to the date of the actual positive test].”
Jones contacted IDPH last week by email, asking for an explanation of “why new positive COVID cases were added to dates as far back as March over the last week. This has been a consistent occurrence since I started following the data.”
Jones pointed out in her email to IDPH that the backdating problem calls into question all decisions that have been made based on the department’s assessment of testing data.
“If cases are just being added as far back as the start of the pandemic on a regular basis, how can this information be trusted as our guidance?” she asked.
Dr. Megan Srinivas, an infectious disease physician in Fort Dodge, said that the error Jones uncovered is “one of the worst data errors that could be happening right now. We are making these policy calls based on completely flawed numbers and that needs to be acknowledged,” Ryan Foley of the Associated Press reported.
In his email last Friday to Jones, Ramaekers said, “We recognize this is a problem and have been working on logic to handle it. We are shifting to using the first positive lab collection date. This change could happen as early as today.”
As of noon on Monday, the error had still not been fixed.
Jones also shared with Belin a spreadsheet she created that documents the extent of the backdating problem. The spreadsheet records daily positive cases and 14-day rolling averages from the time COVID-19 cases were first confirmed in Iowa at the beginning of March to May 27. The spreadsheet shows those numbers as they were published on IDPH’s site on May 27, when Jones first downloaded the data from the site, as well as the numbers for those same days that IDPH published on Aug. 14.
“All told, the more recent version of the website showed 2,396 more COVID-19 cases as having occurred through May 27,” Belin reported, describing the extent of the backdating revealed by the spreadsheet.
Case totals for most dates in March had increased by single digits, but the discrepancies grew larger in April and larger still in May. For some days in late May, the official numbers now show hundreds more positives than had been recorded closer to that time.
Jones told Belin in an email on Monday that she has also examined discrepancies in positive case totals IDPH reported on July 31 and the totals it reported on Aug. 14.
“Her preliminary finding is that the more recent numbers show 5,132 more COVID-19 cases recorded between May 28 and July 31 [on Aug. 14], compared to figures that appeared online July 31,” Belin said.
Gov. Reynolds has consistently said all her decisions regarding COVID-19 are driven by the data collected by IDPH, and has routinely praised the data management system created by Utah-based tech companies as part of the $26 million no-bid contract she awarded them to run Test Iowa.
Many journalists and news organizations have noted discrepancies in the COVID-19 numbers reported by IDPH, but Ramaekers’ email to Jones is the first time the department has publicly acknowledged a problem with its data management system.
Although the backdating problem has caused recent cases of the virus to be underreported by IDPH, it has not affected the overall case count for Iowa, the AP’s Foley noted.
“Iowa’s overall number of more than 52,600 who have tested positive since March is not affected — a per capita rate that is 17th highest among states and the highest in the Midwest, according to Johns Hopkins University.”
Asked for comment on the error in IDPH’s data management system for COVID-19 test results, a departmental spokesperson told Foley “she hoped to have more information about the issue soon.”