Snowball sampling*

Collecting a group of participants, and gaining the rest of the sample through recruitment from these participants themselves.

For example, 5 psychology research students could choose 10 friends each to create a sample of 50 people.

Snowball sampling can allow you to access people that you may not otherwise be able to recruit. For example, people who take drugs or have addictions.

It can however have bias as people’s friends or family are likely to share characteristics, meaning the sample is not representative of a wide enough group of people to be accurately representative.