eprintid: 10202984 rev_number: 7 eprint_status: archive userid: 699 dir: disk0/10/20/29/84 datestamp: 2025-01-07 16:05:47 lastmod: 2025-01-07 16:05:47 status_changed: 2025-01-07 16:05:47 type: article metadata_visibility: show sword_depositor: 699 creators_name: Bountziouka, Vassiliki creators_name: Panagiotakos, Demosthenes B title: The Role of Rotation Type used to Extract Dietary Patterns through Principal Component Analysis, on their Short-Term Repeatability ispublished: pub divisions: UCL divisions: B02 divisions: D13 divisions: G25 keywords: Multivariate analysis, principal, components analysis, rotation type note: © The Author(s), 2022. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. https://creativecommons.org/licenses/by/4.0/ abstract: Principal components analysis (PCA) is a widely used technique in nutritional epidemiology, to extract dietary patterns. To improve the interpretation of the derived patterns, it has been suggested to rotate the axes defined by PCA. This study aimed to evaluate whether rotation influences the repeatability of these patterns. For this reason PCA was applied in nutrient data of 500 participants (37 ± 15 years, 38% male) who were voluntarily enrolled in the study and asked to complete a semi-quantitative food frequency questionnaire (FFQ), twice within 15 days. The varimax and the quartimax orthogonal rotation methods, as well as the non-orthogonal promax and the oblimin methods were applied. The degree of agreement between the similar extracted patterns by each rotation method was assessed using the Bland and Altman method and Kendall’s tau-b coefficient. Good agreement was observed between the two administrations of the FFQ for the un-rotated components, while low-to-moderate agreement was observed for all rotation types (the quartimax and the oblimin method lead to more repeatable results). To conclude, when rotation is needed to improve food patterns’ interpretation, the quartimax and the oblimin methods seems to produce more robust results. date: 2022-08-04 date_type: published publisher: School of Statistics, Renmin University of China official_url: https://doi.org/10.6339/JDS.2012.10(1).1013 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2105959 doi: 10.6339/JDS.2012.10(1).1013 lyricists_name: Bountziouka, Vasiliki lyricists_id: VBOUN85 actors_name: Bountziouka, Vasiliki actors_id: VBOUN85 actors_role: owner full_text_status: public publication: Journal of Data Science volume: 10 number: 1 pagerange: 19-36 issn: 1680-743X citation: Bountziouka, Vassiliki; Panagiotakos, Demosthenes B; (2022) The Role of Rotation Type used to Extract Dietary Patterns through Principal Component Analysis, on their Short-Term Repeatability. Journal of Data Science , 10 (1) pp. 19-36. 10.6339/JDS.2012.10(1).1013 <https://doi.org/10.6339/JDS.2012.10%281%29.1013>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10202984/1/P035_Bountziouka%20et%20al_Rotation-repeatbility_J%20Data%20Sci%202012.pdf