Snowball Sampling: A Purposeful Method of Sampling in Qualitative Research

Abstract

Background and Objectives: Snowball sampling is applied when samples with the target characteristics are not easily accessible. This research describes snowball sampling as a purposeful method of data collection in qualitative research. Methods: This paper is a descriptive review of previous research papers. Data were gathered using English keywords, including "review," "declaration," "snowball," and "chain referral," as well as Persian keywords that are equivalents of the following: "purposeful sampling," "snowball," "qualitative research," and "descriptive review." The databases included Google Scholar, Scopus, Irandoc, ProQuest, Science Direct, SID, MagIran, Medline, and Cochrane. The search was limited to Persian and English articles written between 2005 and 2013. Results: The preliminary search yielded 433 articles from PubMed, 88 articles from Scopus, 1 article from SID, and 18 articles from MagIran. Among 125 articles, methodological and non-research articles were omitted. Finally, 11 relevant articles, which met the criteria, were selected for review. Conclusions: Different methods of snowball sampling can be applied to facilitate scientific research, provide community-based data, and hold health educational programs. Snowball sampling can be effectively used to analyze vulnerable groups or individuals under special care. In fact, it allows researchers to access susceptible populations. Thus, it is suggested to consider snowball sampling strategies while working with the attendees of educational programs or samples of research studies.

COVID-19 Fear in Eastern Europe: Validation of the Fear of COVID-19 Scale

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Measuring Patients’ Perception and Satisfaction with the Romanian Healthcare System

“…This sampling technique offers practical advantages such as having the social networks of identified participants that can provide an ever-expanding set of potential contacts [39][40][41]. Sampling continues until data saturation [42]. Snowball sampling is a more formal methodology that allows inferences to be made about a population of individuals who have been difficult to count by descending methods such as household surveys [39][40][41].…”

“…The questionnaires were voluntarily implemented by second year students from the Faculty of Business, Babes , -Bolyai University, enrolled in a marketing course. They split the questionnaires out into groups of friends and families, considering various categories of respondents' age and residence, who have accessed health services from different medical specialties [42]. The participation in the interview was voluntary and the perceptions and attitudes recorded during the interviews were used only for the purpose of the present paper.…”

Ontological Misconception in Mathematics Teaching in Elementary Schools

“…Responses of answers from questionnaires were identified and analyzed in terms of types of errors, then grouped into types of misconceptions: (1) pre-conception, (2) under-generalization, (3) over-generalization, (4) modelling error, (5) prototyping error; or (6) error processes (Ben-Hur, 2006;Diyanahesa, Kusairi, & Latifah, 2017;Saputri & Widyaningrum, 2016). Based on the misconception data, teacher representatives were then selected through a purposive snowball technique to get the subjects interviewed (Naderifar, Goli, & Ghaljaie, 2017). The following is the flow of research implementation in Figure 1.…”