Validation of a sports nutrition knowledge questionnaire for track and field athletes

Abstract

Abstract Background Proper validation of a newly developed sports nutrition knowledge questionnaire is crucial to ensure that health professionals and coaches can confidently assess athletes' nutrition knowledge, which is known to impact athletes' food choices. This study aims to validate the Athletic-Sports Nutrition Knowledge Questionnaire (A-SNKQ), specifically tailored for Sri Lankan track and field athletes. Methods Content validity was determined by translating the ratings of items by sports nutrition experts into a content validity index. Face validity was assessed via in-depth telephone interviews with elite track and field athletes, using a retrospective think-out-loud protocol. Three groups—doctors with post-graduate qualifications in human nutrition (NTG), banking professionals (NNTG), and elite or semi-elite track and field athletes (AG)—were engaged for the execution of construct validity. Cronbach's alpha was calculated to assess internal consistency, and the correlation coefficient between the two test attempts (test-retest reliability) was determined to evaluate reproducibility. Results The final tool comprised 123 individual items, formulated as 32 questions within 12 sub-sections. Content validity was confirmed by fully integrating 49 out of 70 comments received for each sub-section and partially integrating 4 comments. Face validity was established by fully integrating 33 comments out of the total (n = 40) received from 16 athletes. Construct validity was confirmed using the Kruskal-Wallis test, indicating significant differences in the total scores achieved as a percentage of the A-SNKQ among the NTG (462.5, 92.5%), NNTG (223.5, 44.7%), and AG (235, 47.0%; p < 0.001). Reproducibility was established by strong test-retest reliability between individuals' scores on two test attempts, three weeks apart (r = 0.98, p < 0.05). Internal reliability for each sub-section met psychometric reliability requirements (Cronbach's α > 0.7). Conclusion The A-SNKQ meets all psychometric measures, providing a new, valid, and reliable tool to assess general and sports nutrition knowledge among Sri Lankan track and field athletes.