This involves tapping into each participant’s social online grid to find more subjects for a study.
As the name suggests, snowball sampling starts small and slowly “snowballs” into a larger sample.
It is sometimes referred to as chain sampling, referral sampling, respondent-driven sampling, or chain-referral sampling.
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At a Glance
Snowball sampling is a non-probability method allowing researchers to tap into hard-to-reach populations.
Often used in qualitative designs, it allows researchers to recruit participants through referrals.
While ideal, getting a random, representative sample isn’t always possible.
In such cases, researchers might turn to another method such as snowball sampling.
There are a number of situations where snowball sampling might be appropriate.
These include:
Is Snowball Sampling Qualitative or Quantitative?
Sample sizes may be smaller in this key in of research, but often results in contextually-rich data.
This can help researchers understand the nuances of what they are studying in a specific population.
These individuals are sometimes known as the “seeds.”
The researcher then asks each participant to provide the names of additional people who meet those criteria.
The seed participants are interviewed and provided with a reward for their participation.
They may then be given “coupons” that they can give to other eligible individuals.
Each coupon contains information that allows recruiters to trace its origins.
Potential participants can then redeem these coupons by enrolling in the study.
Each individual approached for participation is also asked to provide information on potential candidates.
This process is continued until enough subjects have been located.
Pros and Cons of Snowball Sampling
Snowball sampling can have some pros and cons.
Traditional recruitment methods might simply not be able to locate asufficient sample size.
It can also be helpful when participants are difficult to locate.
This can include situations where people might be reticent about volunteering information about themselves or identifying themselves publicly.
Because snowball sampling relies on recruiting people via trusted individuals, people may be more willing to participate.
Somevariablesmight make it less likely for certain people to be referred, which can bias the study outcomes.
Another problem with snowball sampling is that it is difficult to know the size of the total overall population.
It’s also challenging to determine whether the sample accurately represents the population.
Research suggests this sampling method can be a cost-effective way to collect data.
Takeaway
Snowball sampling is one method that psychology researchers may use to recruit study participants.
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