Background: Due to the pandemic, COVID-19 cases and deaths are increasing unexpectedly and precipitately. More importantly, asymptomatic carriers could infect healthy people through sneezing, coughing, and talking. Therefore, mask usage is required to prevent and control COVID-19. Objectives: This study was aimed at examining the knowledge, attitude, and performance levels (KAP) of the Iranian population regarding mask usage to prevent and control the COVID-19 outbreak during a one-month period from early April to early May 2020. Methods: A researcher-made, validated, and reliable questionnaire consisting of 30 questions on knowledge, attitude, and performance regarding mask usage was utilized. Data collection was performed through the online method. To do so, the online questionnaire link was provided for the participants via social networks. The correct and wrong answers were scored 1 and 0 points, respectively. The final score of each dimension was calculated and classified as 0 - 50% (low), 51 - 75% (moderate), and 75% > (good). Results: A total of 1581 participants took part in the study. Although the participants had good attitude (74%) and performance (70.80%), but only 13.70% of them had good knowledge regarding mask usage. Also, significant differences were found between the participants’ knowledge and higher educational levels (P < 0.001). There were significant associations between the participants’ age, gender, educational level, and job and their knowledge and attitude levels (P < 0.05). Besides, female participants had higher performance scores than did male participants (P < 0.001). The participants with governmental jobs had significantly higher performance than unemployed ones (P < 0.001). Conclusions: The participants obtained low KAP scores; therefore, it is required to train and inform the society and enhance their KAP levels via social media regarding the importance of mask usage, including proper donning, doffing, cleaning, disinfection, and safely and hygienic disposal procedures of masks to prevent and control COVID-19.
