Figure 1.

Odds ratios for characteristics for COVID-19, sampling, room ventilation, and AGPs for positive air samples. ¹Ct value of patient diagnostic SARS-CoV-2 PCR test collected within 5 days from air sampling. ²Odds ratio for every category (<1 m, 1–2 m, 2–4 m) away from the patient’s head. ³Ongoing specific category versus no ongoing specific category—for example, HFNC versus no HFNC (all other air samples). ⁴Logistic regression adjusted for room ventilation; enhanced, including HEPA-filtration unit or normal ventilation. Abbreviations: AGP, aerosol-generating procedure; CI, confidence interval; COVID-19/Covid-19, coronavirus disease 2019; Ct, cycle threshold; HEPA, High-Efficiency Particulate Air; HFNC, high-flow nasal cannula; PCR, polymerase chain reaction; PEP, positive expiratory pressure; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.