Before revision:  The TND shows differences in risk factors between symptomatic persons with COVID-19 and persons with other respiratory infections . Factors that are risk factors of equal magnitude for both COVID-19 and other respiratory infections will not be identified by the TND.
After revision:  The TND shows differences in risk factors between symptomatic persons with COVID-19 and persons with other respiratory infections (test-negatives). However, risk factors with effect sizes of equal magnitude for both COVID-19 and other respiratory infections will not be identified by the TND.