2. What is Randomisation?

Randomisation is the process of making something random (assigned by chance). This can be applied in:
  • Drawing a random sample of a population.
  • Allocating units to different conditions with no order.
In clinical trials, randomisation refers to the process of assigning a trial participant into treatment or control groups (or arms) using an element of chance to determine the assignments. This procedure is applied in order to reduce bias.

There are two components to randomisation:
  1. The generation of a random sequence.
  2. Its implementation.
The assignment can be done using different tools, such as envelopes, random numbers, scratch sheets, and computer-generated sequences.