השוואת שיטות

	דגימה תכליתית מבוססת ניתוח רגישות	דגימת כדור שלג
תחום	מתודולוגיית סקרים	מתודולוגיית סקרים
משפחה	Process / pipeline	Process / pipeline
שנת המקור	1990s–2000s	1961
הוגה השיטה	Rooted in Patton's purposive sampling typology; sensitivity analysis practices formalized in research synthesis literature	Leo A. Goodman
סוג	Purposive qualitative sampling with robustness verification	Non-probability sampling technique
מקור מכונן	Patton, M. Q. (2015). Qualitative Research and Evaluation Methods (4th ed.). Sage Publications. ISBN: 978-1412972123	Goodman, L. A. (1961). Snowball sampling. Annals of Mathematical Statistics, 32(1), 148–170.
כינויים	purposive sampling with sensitivity checks, robust purposive sampling, sensitivity-tested purposive selection	chain-referral sampling, network sampling, respondent-driven sampling, referral sampling
קשורות	5	3
תקציר	Sensitivity analysis-based purposive sampling extends conventional purposive sampling by systematically testing whether key findings or case-selection decisions change when the inclusion criteria, selection logic, or boundary conditions are altered. It applies the logic of sensitivity analysis — standard in quantitative research and systematic reviews — to qualitative case selection, giving researchers explicit evidence of how robust their purposive choices are to plausible alternative selection rules.	Snowball sampling is a non-probability recruitment technique in which initial participants (seeds) refer the researcher to others who meet the study criteria, and those referrals in turn refer further participants. The sample grows incrementally — like a rolling snowball — until the required size or theoretical saturation is reached. It is the method of choice when a target population has no accessible sampling frame, such as undocumented migrants, illicit drug users, survivors of stigmatised experiences, or members of closed professional networks.