Objective To optimize a nutrition and health literacy questionnaire (NHLQ) for Chinese primary school students previously developed by domestic researchers and empirically apply the modified NHLQ in evaluating nutrition health literacy among pupils in Ningbo city, Zhejiang province.

Methods The NHLQ with 3 subscales for pupils of grade 1 – 2, 3 – 4, and 5 – 6 were modified according to Rash model-based assessment and the optimized HHLQ was evaluated with Winsteps 3.66.0 software. Then the optimized NHLQ was self-administered during June 2023 among 1 868 grade 1 – 6 pupils conveniently recruited at 3 urban and 3 township primary schools in a district of Ningbo city with stratified cluster random sampling. SPSS software was used in data analysis.

Results Valid responses were collected from 99.6% (1 861) of the pupils surveyed. The discrimination of the NHLQ subscales for low- (1 – 2), middle- (3 – 4), and high- (5 – 6) grade pupils were 11.95, 10.41, and 10.14, the reliabilities for the three subscales were of the same value of 0.99. For all the pupils, the average overall score of the NHLQ was 73.8 ± 13.1, with the average scores of 71.4 ± 16.5, 74.8 ± 23.7, and 67.7 ± 23.6 for dietary nutrition knowledge, dietary behavior and habit, and food nutrition label recognition, respectively. The average overall score of the NHLQ for low-, middle-, and high-grade pupils were 77.5 ± 11.5, 75.7 ± 13.4, and 70.9 ± 12.1, showing a downward trend with the schooling grade. The average overall score of the NHLQ of the girl pupils was higher than that of the boy pupils (74.0 ± 12.6 vs. 73.5 ± 13.5) and there was no significant difference in the average overall score between urban and township pupils. The highest correlation was observed between the score of dietary nutrition knowledge and that of food nutrition label recognition, with a correlation coefficient of 0.213.

Conclusion The optimized NHLQ could be used in the assessment on nutrition and health literacy of primary school students in China. The empirical survey with the optimized NHLQ resulted in a relatively low nutrition and health literacy score for the primary school students in Ningbo city and the scores of nutrition cognition, eating habits and nutrition skills differed by schooling grade. The results suggest that targeted education on nutrition and health need to be promoted in the pupils.