14. November 2022

Choosing a study design


Successful development of medicinal products for children always relies on the commitment of parents and children. The significance of the data obtained primarily depends on the study design.

The following terms are used to describe a study:



Randomised: The decision as to which treatment is assigned to which patient is based on the principle of chance. “Principle of chance” means control by a computer on the basis of a defined “distribution principle” determined by statistical methods. This allows patients to be allocated to treatment arms in a well-balanced way, thus ensuring comparability..

Placebo-controlled: Unlike the first treatment group that receives a dummy drug (containing no active ingredient), the second group is given the actual agent. This makes it possible to distinguish between effects solely based on expectations and actual drug effects. Placebos are very rarely used in studies on children and adolescents.

Double-blind: Neither the patients and their families nor the medical team know whether a patient receives standard treatment or the investigational agent. Medicinal products are provided in a controlled manner, in neutral packages and comparable preparations. This helps to avoid distorted expectations regarding the results.


Actively controlled: The patients, their families and the medical team are informed about the patients’ allocation to the respective treatment arms. In this case, the new investigational agent is examined with reference to the standard medication, so as to be able to compare the tolerability and effects of the two products.