Snowball Sampling

Also known as: Chain Referral Sampling, Network Sampling, Snowball Method

Qualitative technique where participants refer other participants with similar characteristics, useful for hard-to-reach populations.

Snowball Sampling is a non-probability sampling technique where initial participants refer or recruit other participants with similar characteristics, who in turn refer others, creating a 'snowball' effect.

It is especially useful for researching populations that are difficult to reach or identify through conventional methods: niche experts, low-penetration product users, specific communities (e.g., vegans, technology early adopters, rare disease patients).

Its main limitation is that the resulting sample is not representative of the general population: it tends to over-represent social networks and specific communities of the initial participant. For this reason, it is primarily used in exploratory qualitative research.