2.6. Data Management
The study used both self-administered and specialist-administered questionnaires completed as face-to-face interviews, paper-and-pencil tests, or, later in the study, on-line surveys. The samples included blood collected by qualified nurses and stool samples collected by the participants. Data entry was validated by the principal study investigator, and data review was performed by the co-investigators. The data was catalogued in a standardized way in compliance with the requirements of findability, accessibility, interoperability, and reusability (FAIR) standards and according to the General Data Protection Regulation (EU) 2016/679 (GDPR). All study participants provided their informed consent to data processing for one or more purposes. To ensure confidentiality, all patients were provided individual specific ID codes which were used to refer to data in the informed consent. The CC-BY-NC-ND 4.0 creative common license schema was applied.