Every morning, participants’ QoL factors were assessed via completion of the WURSS-21 questionnaire and the additional QoL questions based on the effects of the study product used on the previous day. For example, the scores reported on day 1 show the results from day 0. As per leaflet instructions, xylometazoline hydrochloride 0.1% was used no more than three times a day for up to 7 days and participants had the option to stop treatment at their discretion (Supplemental Methods Section 6) based on their desire to treat nasal congestion. Opting out of the treatment before the completion of 7 days of treatment was possible if participants felt their symptoms did not warrant further treatment, or if their nasal congestion was resolved; both criteria were assessed daily. The last dose was the day of last treatment if before 7 days. On day 7, or on the day after the last dose was used, participants completed an exit survey. Participants who did not satisfy the criteria for participation and treatment compliance (Supplemental Methods Section 7) were considered dropouts.