After county health officials noted a discrepancy between its and Purdue's coronavirus data over the summer, Exponent reporting found another difference in this week's numbers.
The issue occurred again Wednesday, when Purdue reported 18 positive tests but the county's data shows only nine positive results total.
Results are displayed by the date tests were performed, according to explanations on both websites.
Purdue's results are returned within two to three days, according to Dr. Esteban Ramirez, chief medical officer at the Protect Purdue Health Center. This means a positive test for COVID-19 on Monday won't be reported until Wednesday or Thursday.
The 18 cases the University reported Friday, the single-largest daily increase to date, are attributed to Wednesday on Purdue's dashboard.
"All data is preliminary and likely to change as additional test results are received," Purdue says on its dashboard, "leading to the number of tests and/or cases on a given day going up a few days later."
ISDH attaches a similar disclaimer to its statewide map tracking cases.
Purdue's overall positivity rate since Aug. 1 sits at 2.22%, with 221 total positive tests reported.
Khala Hochstedler, administrator for the Tippecanoe County Health Department, explained how the county's total case count might outnumber Purdue's. Hochstedler did not immediately respond to later emailed questions asking how the opposite has happened.
Purdue spokesperson Tim Doty said the University "immediately reports results directly to ISDH, who in turn updates the local information for all 92 counties in Indiana."
He also noted that not everyone tested for the coronavirus at Purdue lives in Tippecanoe County, implying that students who live in different counties or states are counted in their home counties, despite living on campus.
In July discrepancies were found between county data and testing results within Purdue Athletics, which prompted the Tippecanoe County Health Department to create a backup system for reporting positive cases with the University.
Tippecanoe County recorded 54 new coronavirus cases on Thursday, the largest number of new cases in a single day since ISDH began reporting in March.
The county administered its largest number of tests Thursday, 1,556, with an 11.2% positivity rate.
The recent results raised the seven-day average for Tippecanoe County from 18 to 24 new cases per day, bringing the county's total positive cases up to 1,690.
Asst. Sports Editor Joe Duhownik, Graphics Editor Adrian Gaeta and Managing Editor Jordan Smith contributed reporting.