Σύγκριση μεθόδων

	Διαχρονική Αξιολόγηση Προγραμμάτων	Ανάλυση Διακοπτόμενης Χρονοσειράς (ITS)	Έρευνα Επιμήκους Τροχιάς	Αξιολόγηση Προγράμματος
Πεδίο	Μέθοδοι Πεδίου	Αιτιακή Συμπερασματολογία	Ερευνητικός Σχεδιασμός	Μέθοδοι Πεδίου
Οικογένεια	Process / pipeline	Regression model	Process / pipeline	Process / pipeline
Έτος προέλευσης	1960s–1970s (program evaluation); longitudinal designs formalized 1970s–1980s	2002	Late 19th–early 20th century; methodologically codified through the 20th century	1960s–1970s (Scriven 1967; Stufflebeam CIPP model 1971)
Δημιουργός	Peter Rossi, Michael Scriven, Donald Campbell (program evaluation tradition)	Wagner, Soumerai, Zhang & Ross-Degnan (segmented regression); Bernal, Cummins & Gasparrini (tutorial)	No single originator; foundational methodological treatments by Stuart Menard and Judith Singer & John Willett	Michael Scriven; Daniel Stufflebeam; Peter Rossi
Τύπος	Applied evaluation research design	Quasi-experimental segmented regression	Quantitative (or mixed) observational research design	Applied evaluation methodology
Θεμελιώδης πηγή	Rossi, P. H., Lipsey, M. W., & Freeman, H. E. (2004). Evaluation: A Systematic Approach (7th ed.). Sage Publications. ISBN: 978-0761908944	Bernal, J. L., Cummins, S., & Gasparrini, A. (2017). Interrupted time series regression for the evaluation of public health interventions: a tutorial. International Journal of Epidemiology, 46(1), 348-355.	Menard, S. (2002). Longitudinal Research (2nd ed.). Sage Publications. ISBN: 978-0761922841	Rossi, P. H., Lipsey, M. W., & Freeman, H. E. (2004). Evaluation: A Systematic Approach (7th ed.). Sage. ISBN: 978-0761908944
Εναλλακτικές ονομασίες	LPE, longitudinal evaluation, long-term program evaluation, prospective program evaluation	ITS analysis, segmented regression of time series, Kesintili Zaman Serisi (ITS) Analizi	longitudinal study, longitudinal design, prospective longitudinal study, repeated-measures observational study	evaluation research, program assessment, educational evaluation, systematic program evaluation
Συναφείς	3	5	4	3
Σύνοψη	Longitudinal program evaluation is an applied research design that tracks the outcomes and processes of a program or intervention across multiple time points — from pre-implementation baseline through medium- and long-term follow-up. Unlike single-point evaluations, it captures how program effects emerge, fade, or evolve over time, enabling evaluators and funders to judge sustained impact, cost-effectiveness, and unintended consequences that would be invisible in a snapshot assessment.	Interrupted Time Series analysis is a quasi-experimental design that estimates the effect of a single, well-dated intervention by comparing the trajectory of an outcome before and after it occurs. Formalised as segmented regression by Wagner and colleagues (2002) and popularised as a public-health evaluation tutorial by Bernal, Cummins and Gasparrini (2017), it separates the intervention's impact into a change in level and a change in slope.	Longitudinal research is an observational design in which the same participants, groups, or units are measured repeatedly over an extended period. Rather than capturing a single snapshot, it tracks change, stability, and temporal sequencing of variables — making it the primary non-experimental strategy for studying development, growth, decline, and the unfolding of causal processes across time.	Program evaluation is a systematic, empirically grounded process of collecting and analyzing information about a program to determine its merit, worth, or significance. Applied across education, public health, social services, and policy, it addresses questions such as whether a program is reaching its target population, whether it is being implemented as designed, and whether it is producing the intended outcomes. It draws on both quantitative and qualitative methods and serves accountability, improvement, or knowledge-generation purposes.