Although many methods have bee used, it remains unclear how to define fussy/picky eating.
Link to Publication: http://www.ncbi.nlm.nih.gov/pubmed/?term=24512388
Tharner A, et al. Toward an operative diagnosis of fussy/picky eating: a latent profile approach in a population-based cohort. International Journal of Behavioral Nutrition and Physical Activity 2014; 11:14.