Associations between symptom duration and patient characteristics including sex (males (reference) vs. females), age, BMI, ethnicity (White/European (reference) vs. Non-White/European), viral variant (wild-type (reference) vs. viral variant), vaccination status (unvaccinated (reference) vs. vaccinated), and underlying medical conditions (none (reference) vs. any). Regression coefficients and 95% confidence intervals were calculated using an interval regression model. Regression coefficients correspond to the difference in symptom duration (in weeks) compared to the reference group (for categorical variables), or for a one-year increase in age or one-unit increase in BMI. Statistically significant associations are indicated by asterisks (*).