Clinical trial

A clinical trial is a research investigation conducted in a clinical setting, designed to generate data on the efficacy and/or safety of a drug, device, treatment, or other healthcare intervention. Clinical trials are usually characterised by clearly defined hypotheses, strict eligibility criteria, randomisation (if possible), blinded administration and outcome measurement (if possible), pre-specified protocols and analysis plans, ethical approval, and comprehensive reporting. While crucial for establishing internal validity, their controlled nature can sometimes limit the generalisability of findings to more diverse real-world populations. Clinical trials of medicinal products involving human subjects adhere to Good Clinical Practice (ICH-GCP) guidelines, ensuring high ethical and scientific standards throughout planning, execution, and reporting, with regulatory oversight. These trials are registered in databases such as ClinicalTrials.gov (USA) and the EU Clinical Trials Register, accessible via the WHO International Clinical Trials Registry Platform. Trials are typically sponsored by government organisations, academic research institutes, manufacturers, or charities.