What sampling method is described as "friend telling friend"?

The sampling method described as "friend telling friend" is snowball sampling. This method is particularly useful in qualitative research, especially when studying hard-to-reach or hidden populations. In snowball sampling, existing study participants recruit future subjects from among their acquaintances. This process resembles a snowball effect, where the initial subjects help to gather more participants, allowing researchers access to a wider network than they might reach through traditional sampling techniques.

This method is advantageous because it can generate a sample that is more representative of a specific social group that may be difficult to identify or contact through standard approaches. It relies on personal connections and trust, which is vital in research involving sensitive topics.