A cross sectional survey assessing the general public’s knowledge and practice regarding face mask use.
The data collection was done during 15th May to 20th June, 2020, when the country was under lockdown due to COVID-19.
The study was conducted at Dharan, a city located in the eastern part of Nepal with a population of approximately 1,50,000, located closed to the border with India. This city was selected since it has a mixture of population in terms of age, gender, ethnicity, educational qualifications etc., who would be available at the time of lockdown as the city hosts a large number of healthcare and educational centers.
Any individual willing to participate in the study as per the inclusion and exclusion criteria were enrolled. A mixed population with multiple knowledge levels, and from multiple professions covering both genders were enrolled.
Sample size calculation
The sample size was calculated using Raosoft sample size calculator using the formula below 
Sample size = Z2*(p)* (1-p)/c2
Where, c = margin of error, P = Prevalence of the characteristic
Thus, the sample size (n) at 95% confidence interval and 5% margin of error
Calculated sample size was n = 1.962 x 0.564 × 0.463 / (0.05)2 = 377.86 ∼ 378
The prevalence (p) value was taken from study conducted by Kumar J et al. in Pakistan 
The calculated sample size was 378 and a total of 380 responses were collected
Since Dharan has a mixed population it was difficult to identify a definite population at a definite locality. Ten areas spread uniformly through the city were identified and pharmacist having pharmacy in those localities were contacted to serve as data collection centers. The community pharmacists were trained by the principal investigator (KA) on aspects such as contents of the questionnaire, obtaining participants’ consent and responses from the general public while maintaining social distancing, stratification of sample, and entering the responses.
Inclusion and exclusion criteria
Individuals of both gender who had completed 15 years of age were considered eligible for the study. Any individual visiting the pharmacies with respiratory symptoms or unwilling to respond to the survey were excluded.
Stratification of study sample: The stratification of the total sample of 378 was based on the National demographic data of Nepal- 2019 . The gender distribution was stratified as 0.96 males per 1 female, age group 15–40 yrs. 50% and above 40 yrs. 50%; literate (56%) versus illiterate (44%): urban 20.2% rural: 79.8% However, due to ongoing lockdown strict stratification could not be maintained during the study.
Study questionnaire: The study questionnaire was designed by the researchers based on their understanding and referring to WHO guidelines on face mask use published during the COVID-19 pandemic . The questionnaire had two parts Part I: Demography, Part II: General public knowledge and practice on face mask use and related aspects
Part I: Part I: Demography
This part collected information on age, gender, educational qualifications, occupation and ethnicity.
Part II: General public knowledge and practice on face mask use and related aspects
This part had a total of 18 questions; 5 ‘yes or no’ questions, one right or wrong question, two open ended questions on how to dispose face masks and methods other than face mask effective in preventing or reducing the impact of COVID-19, and the last question examining the five steps on correct use of face mask recommended by the WHO . There were also 9 statements scored using a 3-point Likert type questions with responses of agree, neutral and disagree. The final version of the study questionnaire was translated into Nepali following the forward-and-backward process. Thus, the version provided to pharmacists was in Nepali language which was then subjected to pilot testing.
Validity Of The Questionnaire
The study questionnaire was content validated by the researchers and a public health expert with the questionnaire themes matched with the study objectives. The validity of the questionnaire was noted by pilot testing the questionnaire on ten subjects who were later excluded from analysis in the main study. The reliability was assessed by calculating Cronbach’s alpha. The score was 0.56 upon removal of four questions with poor reliability scores and this modified questionnaire was used in the final study.
Method of data collection
Since the study was conducted during lockdown it was not possible to collect the responses directly from the general public. Hence trained community pharmacy practitioners were contacted to collect the data from their visitors. During the data collection process, personal hygiene and social distancing were maintained and while collecting the responses, both the respondent and the community pharmacists wore face masks. A total of ten pharmacies were identified from various areas of Dharan and the community pharmacists were trained individually by the principal investigator regarding the questionnaire and how to record the responses. The principal investigator oversaw the collection of responses and found the process adequate and appropriate.
The completed questionnaire was verified by the principal researcher and details entered in IBM SPSS Statistics for Windows, Version 26 and the normality of the data checked using one-sample Kolmogorov-Smirnov test (p < 0.05). The demographic parameters were analyzed descriptively and tabulated as number and percentages. Independent-sample median test was used to compare the scores among different subgroups of respondents, at alpha = 0.05. Further post hoc analyses were performed for statistically significant pairs using Bonferroni correction for multiple tests at alpha = 0.05. The number (percentage) of individuals answering each question correctly was noted. The number of individuals who answered all five steps regarding the correct use of a face mask was calculated. The proportion of individuals answering all five steps correctly among different subgroups were compared using chi-square test (p < 0.05).
A pilot study was conducted to perform the feasibility of the study and to identify any technical difficulties in collecting the data.