Abstract
Background: The coronavirus disease-19 (COVID-19) has rapidly emerged as a global pandemic that causes millions of deaths worldwide. It is transmitted from person to person by respiratory droplets and could cause fatigue, shortness of breath, and fever.

Objective: The objective of the study was to assess COVID-19 related knowledge, attitude, and preventive behavior among high school students in Bangkok, Thailand.

Materials and Methods: The study was conducted using a cross sectional online survey among Harrow’s students Y 12–13. A total of 148 students participated. COVID-19-related knowledge, attitudes toward COVID-19, and preventive behaviors were assessed. Differences between outcomes and socio-demographic were analyzed through independent t-test and the Analysis of variance. Preventive behaviors were analyzed by a generalized linear model.

Results: The undergraduate students showed a low knowledge about COVID-19, a mean of 6.38 (standard deviation [SD] = 1.69) questions in a total of 11. However, the result showed a standard level of attitude toward preventive behaviors on COVID-19 with an average score of 47.51 from a score range of 14–70 (SD = 4.45). Finally, preventive behaviors of participants were at a moderate level with an average score of 36.84 from a range from 12 to 60 (SD = 3.93). The data showed a statistically significant positive correlation between attitude toward preventive behavior on COVID-19 and COVID-19 preventive behavior (r = 0.351**, P = 0.01). From a generalized linear model, attitude toward preventive behavior on COVID-19 (Exp (B) = 0.394, Confidence interval [CI]: 0.212–.485, P < 0.05) and Gender (Exp (B) = 0.203, 95%, CI: 0.376–2.807, P < 0.05) can be a predictive factor for the preventive behavior of Harrow International school students.

Conclusions: The results assessed that Harrow international students had a lower level of COVID-19 general knowledge, but moderate level of attitude and preventive behavior. Moreover, it indicates that there is a causal relationship between attitude toward COVID-19 and preventive behaviors. Thus, attitudes toward COVID-19 are a major predictive factor of having preventive behaviors. Therefore, school and parents should always build awareness and provide safety to the students and remind students with rules that should be followed to secure them from risking of COVID-19.

Key words: Coronavirus Disease-19; Preventive Behavior; High School Students