[Analysis of the impact of salt reduction interventions on primary school students' parents based on the home-school interaction model].

To analyze the impact of salt reduction interventions on the knowledge, attitude and behavior regarding the salt reduction of students' parents based on the home-school interaction model. In April 2021, parents of students in grades 3-5 from three primary schools in Yichang City were selected as the target population using a cluster sampling method, and the parent population was divided into an intervention group and a control group. In the intervention group, a comprehensive home-school interaction salt reduction intervention was implemented, and in the control group, no intervention measures were taken for students' parents. Baseline and final surveys were conducted before and after the intervention period, which included general information, previous salt reduction interventions received, and salt reduction knowledge, attitude and behavior. Difference-in-difference (DID) method was used to compare the knowledge, attitude and behavior status of two groups before and after the intervention, and stratified analysis of parents with different literacy levels was conducted to assess the net effect of intervention implementation. The results showed that 740 parents completed the baseline and final surveys, with 231 in the intervention group and 509 in the control group. After propensity score matching, there were 231 (33.33%) in the intervention group and 462 (66.67%) in the control group. After the intervention, the proportion of the intervention group who obtained salt control spoons and pots, as well as salt reduction knowledge and advice through school, was 87.45%, 86.58% and 75.45%, respectively, which was significantly higher than that in the control group (P<0.05). After the intervention, the proportion of parents with a high school and lower education who obtained salt control pots was higher in the intervention group (89.23%) than in the control group (74.49%), with significant differences (P<0.05). The proportion of parents with a college degree or above who obtained salt control spoons and pots, as well as salt reduction knowledge and advice through school, was higher than that of the control group (P<0.05). The results of DID method showed that after controlling for monthly income and other factors, the scores of parents' salt reduction-related knowledge and low-salt behavior in the intervention group increased significantly higher than those in the control group, with DID values (95%CI) of 1.18 (0.15-2.21) and 0.62 (0.16-1.09), respectively, indicating a significant net effect of intervention implication. After stratification according to the education level of parents, this difference still existed in the college degree or above group, with DID values (95%CI) of 1.39 (0.13-2.66) and 0.76 (0.16-1.36), respectively. The home-school interaction model for salt reduction measures can improve the salt-related knowledge and low-salt behavioral choices of students' parents.