Backgrounds data
A total of 1417 questionnaire forms were filled by university students. Distribution of demographic characteristics of the study population is presented in Table 1. Of the participants, 68% were female participants and 32% male with a mean age of 22 years (± standard deviation (SD) ± 2.9). The data shows that the majority of the participants (62.8%) were in the age group of 20-24 years and 79.8% of them were undergraduate students. The students comprised of two educational groups; 41.8% from health-related and 58.2% from non-health related majors. Majority of the respondents' fathers had university education and mothers had college education.
Overall food safety knowledge score
Table 2 presents the mean scores of knowledge sections and overall food safety knowledge. Results showed that the respondents had a moderate knowledge about overall food safety with a mean score of 62.48%. Participants achieved the highest score for the knowledge on causes of foodborne diseases (66.25%) and the lowest score for the knowledge on food handling practices (63.77%).
Table 3 showed the percentages of correct responses for the questions about personal hygiene practices. Majority of the respondents answered correctly for all questions except the question 6, 9 and 10 for which students had poor knowledge. Only 35.3% gave the correct answer for question "It is not safe to store chicken, fish and raw meat together in a fridge or freezer", 88% wrongly believed that "To avoid food poisoning, you should clean the kitchen sink drain every week" and 16.2% did know the correct answer for the question "The best way to avoid food poisoning from fruits and vegetables is to wash them under a running tap".
Descriptive results of knowledge questionnaire in the area of foodborne diseases are presented in Table 4. Respondents had poor knowledge (28.8%) about the consumption of canned vegetable and they believe that its consummation without prior heating will increase one's risk of suffering food poisoning. About 30.8% of the students gave wrong answer to the question about the "Leftover chicken eaten cold can cause foodborne diseases".
This study found that students have a very poor knowledge about the symptoms of foodborne diseases. Majority of the respondents didn't know that body temperature rises quickly (79%), low blood pressure (64.7%), sweats (66.8%), pain in the bone (52.7%), coughing or sneezing (64%) are not the symptoms of foodborne diseases. Only 45.9% students correctly know that stiff neck is also a symptom of the foodborne diseases (Table 5)
Improper food handling practices are thought to contribute to a high number of foodborne illness outbreaks. Data presented in table 6 show the respondents knowledge on food handling practices. Most of the participants (86%) failed to select the correct answer for the question about "Thorough washing of vegetables and fruits in tap water is necessary to prevent food poisoning". Likewise, only 17.1% and 38.4% of the correspondents knew that the food handler should be medically examined every six months and they cannot clean their hands by wiping them on a piece of cloth, respectively. Over half of the respondents (53.7%) believed that it is unnecessary to reheat the previously cooked food.
Impact of socio-demographic characteristics on students' food safety knowledge
Students aged above 30-year had significantly lower knowledge on all the types of knowledge scores except "symptoms of foodborne diseases" where the score was lower, but the result was non-significant. There was a statistically significant difference between the gender and the knowledge on personal hygiene practices, causes of foodborne diseases, symptoms of foodborne diseases, food handling practice and overall knowledge. Female students showed significantly higher score on all the types of knowledge (Table 7).
Current levels of education of students had no effect on all the types of knowledge scores except the causes of foodborne diseases. Postgraduate students had significantly higher scores for causes of foodborne diseases than undergraduate students. The mean score of all knowledge types of health science students was higher than non-health related students and the difference between means was statistically significant (Table 7).
According to this study, students whose fathers were educated had significantly higher mean knowledge of all groups except personal hygienic practices. Participants whose mother was educated had significantly higher mean score on overall knowledge and knowledge on symptoms of foodborne diseases.
Predictors of food safety knowledge
Multivariate logistic regression analysis was used to explore the significant predictors among the socio-demographic variables for food safety knowledge. As shown in Table 8, regression analysis showed that age, gender, education level, academic discipline and father's education are significantly (P < 0.05) associated with overall food safety knowledge. In the full model, being female (OR = 1.88, P = 0.001), postgraduate students (OR = 1.28, P = 0.001), students from health-related majors (OR = 3.84, P = 0.001) and students who had educated father (OR = 3.87, P = 0.001) were positively associated with adequate food safety knowledge. A negative association was also found between age groups higher than 30 years and overall food safety knowledge (OR = 0.09, P = 0.001). For personal hygiene practices knowledge, age group 20-24 (OR = 1.82, P = 0.001), 25-29 years (OR = 2.05, P = 0.017), health-related majors (OR = 3.16, P = 0.001) and father’s education (OR = 2.21, P = 0.029) were positively associated with adequate knowledge. In addition, female gender (OR = 0.67, P = 0.004), being in age group of >30 years (OR = 0.34, P = 0.040) and having higher education (OR = 0.62, P = 0.004) were negatively associated to the personal hygiene practices knowledge. As for the knowledge on causes of foodborne diseases, being in age group 20-24 (OR = 1.31, P = 0.037) and 25-29 years (OR = 2.07, P = 0.021), female gender (OR = 10.268, P = 0.064), having higher education (OR = 1.421, P = 0.035), health-related majors (OR = 2.057, P = 0.001) and father’s education (OR = 3.340, P = 0.001) were positively associated with adequate knowledge. In addition, being in age 25-29 years (OR = 2.07, P = 0.021), female gender (OR = 10.268, P = 0.064), health-related majors (OR = 2.057, P = 0.001) and educated father (OR = 3.340, P = 0.001) were positively associated with adequate knowledge on symptoms of foodborne diseases. The subjects in age groups above 30 years with a high education level were more likely to have inadequate knowledge on symptoms of foodborne diseases. Age group 20-24 (OR = 0.72, P = 0.010) and mother’s education (OR = 039, P = 0.001) revealed a negative relationship with knowledge on of foodborne diseases.