Comparer des méthodes

	Groupe de discussion longitudinal	Enquête longitudinale
Domaine	Méthodologie d'enquête	Méthodologie d'enquête
Famille	Process / pipeline	Process / pipeline
Année d'origine	1940s (focus groups); longitudinal variant refined 1980s–1990s	1940s (panel survey tradition); longitudinal designs codified mid-20th century
Auteur d'origine	Adapted from Robert K. Merton's focused interview tradition; longitudinal design developed in social and health sciences	Established tradition; formalized in social science by Paul Lazarsfeld and colleagues (1940s panel studies)
Type	Qualitative longitudinal data collection	Quantitative / mixed-methods survey design
Source fondatrice	Morgan, D. L. (1997). Focus Groups as Qualitative Research (2nd ed.). Sage Publications. ISBN: 978-0761903437	Menard, S. (2002). Longitudinal Research (2nd ed.). Sage Publications. ISBN: 978-0761922292
Alias	repeated focus group, panel focus group, longitudinal FG, follow-up focus group	panel survey, repeated-measures survey, longitudinal panel study, wave survey
Apparentées	5	3
Résumé	A longitudinal focus group convenes the same group of participants in multiple sessions over an extended period — weeks, months, or years — to trace how their attitudes, experiences, or interpretations evolve in response to changing circumstances. Unlike a single focus group snapshot, the repeated-contact design captures the dynamics of opinion and meaning-making across time, making it particularly valuable in health, policy, and social research where change is the phenomenon of interest.	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.