Study types

A clinical study is a research study using human subjects to evaluate biomedical or health-related outcomes. On the English version of this website, clinical studies are divided up into the subsidiary groups clinical trials and observational studies.

Clinical trials

Clinical trials are sometimes called intervention studies or experimental studies. Within the framework of a clinical trial, study participants are exposed to some kind of intervention, for example a medicine, a medical device, a diet or a surgical method according to a previously agreed protocol. The purpose is to investigate or confirm the safety or effect of the therapy or method.

In a controlled clinical trial, the new therapy or method is compared with a control consisting of an established therapy or method, placebo or no measure at all. In a randomised controlled trial, the study participants are allocated randomly between the treatment groups.

Clinical trials with a medicine or a medical device need approval from the Medical Product Agency before they can start.

Observational studies

Observational studies are sometimes called non-intervention studies, or non-experimental studies. No active measure is taken, instead the study participants are observed during current circumstances. Observational studies may, for example, consist of ecological or epidemiological investigations, cross-section investigations, cohort investigations or case-control investigations.