The need to respect the trial participants’ willingness regarding the secondary use of their data to conduct research such as meta-analyses has been recently discussed [1]. The best approach is to include a sentence in the trial’s participant information sheet/informed consent form (PIS/ICF) requesting the participant’s consent to the future use of the data by third parties. This must be conducted by preserving the participant’s privacy by deidentifying individual participant data (IPD). De-identification can be in two forms: pseudonymization (participant, if needed, can be identified) or anonymization (data cannot be linked to a participant) [1].
