PMC:4137988 / 20327-21338 JSONTXT

{"project":"2_test","denotations":[{"id":"25143747-11790957-55576550","span":{"begin":481,"end":483},"obj":"11790957"},{"id":"25143747-9663398-55576551","span":{"begin":873,"end":875},"obj":"9663398"}],"text":"Two approaches, a priori and a posteriori, have been used to generate dietary patterns. Both approaches have strengths and weaknesses. The a priori approach focuses on a predefined dietary pattern based on prior knowledge of a specific diet (eg, Mediterranean) and its relationship to disease. Therefore, this approach is limited by current knowledge and could involve uncertainties in selecting individual components of the diet index and subjective decisions of defining cutoffs.52 In contrast, the a posteriori approach provides opportunities to open up new areas of diet-disease research and detect dietary patterns specific to the region and/or population of interest. However, it involves important but arbitrary decisions, including the number of components to extract, the method of rotation, consolidation of food items into groups, and labeling of the components.53 Researchers should choose the appropriate method according to the study objectives and dietary characteristics of the study population."}