[Effectiveness on the education and food safety programs among senior primary students in 2 counties from west China-a cluster randomized trial].

Objective: To evaluate the effectiveness of nutrition and food safety educational programs on primary students from grade 4 to 6 in impoverished areas of Western China, under a school-based cluster-randomized trial.
Methods: Twelve primary schools were selected from 2 impoverished counties in West China and assigned to intervention or control groups, randomly, with 6 schools in each group. Self-rating knowledge, attitude and practice questionnaires were used at both baseline and final stages. Textbooks and supportive materials were designed according to the characteristics of baseline data. All students in the intervention group were treated with targeted nutrition and food safety lectures of 0.5 hour per week for 2 semesters. Generalized linear mixed effects model was applied to fit the random effects on individual and clusters as well as to fit the fixed effect of the programs.
Results: Three hundred seventy-eight students from grade 4 to 6 were randomly selected at the baseline study and the differences of scores on knowledge, attitude and practice between the 2 groups were statistically insignificant (P > 0.05). No cluster was lost during the trial. In the final investigation, 478 students were randomly selected at the individual level. Scores on knowledge, attitude and practice among students in the intervention group were significantly higher, when comparing to the control group (P < 0.01). At the cluster level, more schools in the intervention group showed significant changes on knowledge and practice, yet the change in attitude was less obvious. Data from the mixed-effects model demonstrated that the program served as an influential factor on scores related to knowledge after the intervention(P = 0.015)but did not affect the scores on related attitude or practice (P > 0.05).
Conclusion: Lectures seemed to have improved the cognition of nutrition and food safety among primary students from grade 4 to 6. However, long-term observation and larger sample size were needed to evaluate the changes on attitude and practice among the students.