השוואת שיטות

	שיטות איסוף נתונים	שיטות דגימה במחקר
תחום	מתודולוגיית מחקר	מתודולוגיית מחקר
משפחה	Process / pipeline	Process / pipeline
שנת המקור	1980	1950
הוגה השיטה	Floyd Fowler (surveys); John Creswell, Robert DeVellis (qualitative and scale methodology)	William G. Cochran and Leslie Kish (1950s–1970s)
סוג	Framework	Framework
מקור מכונן	Fowler, F. J. (2014). Survey Research Methods (5th ed.). SAGE Publications.	Cochran, W. G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons.
כינויים	data gathering, measurement instruments	sampling strategy, sampling design, probability and non-probability sampling
קשורות	3	3
תקציר	Data collection methods are the specific techniques and instruments used to gather information from research participants or sources. Common quantitative methods include surveys (questionnaires, interviews), physiological measurements (blood pressure, lab assays), behavioral observations, and administrative/secondary data (e.g., medical records, national registers). Qualitative methods include in-depth interviews, focus groups, observations, and document analysis. Selection and design of data collection instruments directly affect data quality, validity, and reliability. Floyd Fowler's work on survey methodology (1980s–2010s), Robert DeVellis's scale development approach, and John Creswell's frameworks for qualitative data collection provide systematic guidance.	Sampling is the process of selecting a subset of individuals, observations, or units (the sample) from a larger population to study. Sampling methods are broadly classified into probability (random) and non-probability (non-random) approaches. Probability methods—random sampling, stratified sampling, cluster sampling, systematic sampling—enable statistical inference to the population and allow calculation of confidence intervals and margins of error. Non-probability methods—convenience, purposive, snowball, quota sampling—are practical for exploratory or qualitative research but do not support formal statistical generalization. Cochran's Sampling Techniques (1977) and Kish's Survey Sampling (1965) are foundational references; modern applications span surveys, experiments, qualitative studies, and clinical trials.