The Environmental and Bitter Taste Endophenotype Determinants of Picky Eating in Australian School-Aged Children 7-12 years-A Cross-Sectional Pilot Study Protocol.

Caregivers' perceptions of children's pickiness are relatively scarce in relation to the five core food groups and their importance in providing a nutritionally balanced diet. Furthermore, there is no validated questionnaire that examines child-reported food preferences in an age-appropriate manner, and the use of terms such as a "picky eater" can be attributed to environmental and genetic factors. Despite potential links between children's food preferences and endophenotype bitter taste, associations between bitter taste sensitivity and picky eating is relatively unexplored. The proposed cross-sectional study aims to develop and validate a parent-reported core-food Picky Eating Questionnaire (PEQ) and child-reported Food Preference Questionnaire (C-FPQ) and simultaneously investigate environmental and phenotype determinants of picky eating. The study will be conducted in three stages: Phase 1, piloting PEQ and C-FPQ questionnaires (15-20 primary caregivers and their children aged 7-12 years); Phase 2 and 3, validating the revised questionnaires and evaluating the 6-n-propylthiouracil (PROP) bitter taste sensitivity to examine perception to bitter taste (369 primary caregivers and their children). Study findings will generate new validated tools (PEQ, C-FPQ) for use in evidence-based practice and research and explore picky eating as a behavioural issue via the potential genetic-phenotype basis of bitter taste sensitivity.