Snowball sampling is a recruitment technique in which research participants are asked to assist researchers in identifying other potential subjects. The use of currently enrolled research participants to recruit additional research participants (sometimes referred to as “the snowball sampling”) may be approved by the IRB under some circumstances. However, the protocol must include justification of the use of this method in the context of the study and target population. The method that minimizes risk would be the preferred choice. For example, a researcher seeking to study patterns of informal leadership in a community may ask individuals to name others who are influential in a community.
