...
https://ec.europa.eu/health/sites/health/files/files/eudralex/vol-1/reg_2014_536/reg_2014_536_en.pdf
"(1)‘Clinical study’ means any investigation in relation to humans intended:
(a) to discover or verify the clinical, pharmacological or other pharmacodynamic effects of one or more medicinal products;
(b) to identify any adverse reactions to one or more medicinal products; or
(c) to study the absorption, distribution, metabolism and excretion of one or more medicinal products;
with the objective of ascertaining the safety and/or efficacy of those medicinal products;
(2)‘Clinical trial’ means a clinical study which fulfils any of the following conditions:
(a) the assignment of the subject to a particular therapeutic strategy is decided in advance and does not fall within normal clinical practice of the Member State concerned;
(b) the decision to prescribe the investigational medicinal products is taken together with the decision to include the subject in the clinical study; or
(c) diagnostic or monitoring procedures in addition to normal clinical practice are applied to the subjects.