Σύγκριση μεθόδων

	Διαχρονική Έρευνα	Διαδικτυακή Έρευνα
Πεδίο	Μεθοδολογία Επισκοπήσεων	Μεθοδολογία Επισκοπήσεων
Οικογένεια	Process / pipeline	Process / pipeline
Έτος προέλευσης	1940s (panel survey tradition); longitudinal designs codified mid-20th century	Mid-1990s (widespread scholarly adoption ~1995–2000)
Δημιουργός	Established tradition; formalized in social science by Paul Lazarsfeld and colleagues (1940s panel studies)	Mick P. Couper, Don A. Dillman (early systematic frameworks)
Τύπος	Quantitative / mixed-methods survey design	Quantitative / mixed-methods data collection technique
Θεμελιώδης πηγή	Menard, S. (2002). Longitudinal Research (2nd ed.). Sage Publications. ISBN: 978-0761922292	Couper, M. P. (2000). Web surveys: A review of issues and approaches. Public Opinion Quarterly, 64(4), 464–494.
Εναλλακτικές ονομασίες	panel survey, repeated-measures survey, longitudinal panel study, wave survey	web survey, internet survey, e-survey, computer-assisted web interviewing
Συναφείς	3	6
Σύνοψη	A longitudinal survey collects structured questionnaire data from the same individuals or units at two or more distinct points in time. By tracking the same respondents across waves, researchers can distinguish genuine change from stable individual differences, establish temporal ordering between variables, and model trajectories of attitudes, behaviors, or outcomes in ways that a single cross-sectional snapshot cannot support.	An online survey is a structured data collection instrument hosted on a web platform and completed by respondents via internet-connected devices. It enables large-scale, geographically dispersed data gathering at low cost and with rapid turnaround. Respondents self-administer the questionnaire at their convenience, which reduces interviewer bias and permits automatic data capture. Online surveys are the dominant mode of survey research in social, behavioural, health, and market research today.