So sánh phương pháp

	Khảo sát trực diện	Khảo sát dọc
Lĩnh vực	Phương pháp luận khảo sát	Phương pháp luận khảo sát
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1930s–1940s (systematic survey era)	1940s (panel survey tradition); longitudinal designs codified mid-20th century
Người khởi xướng	Established practice formalised in survey methodology (Gallup, Likert, and others from the 1930s–1940s)	Established tradition; formalized in social science by Paul Lazarsfeld and colleagues (1940s panel studies)
Loại	Quantitative / mixed-mode data collection	Quantitative / mixed-methods survey design
Công trình gốc	Fowler, F. J. (2014). Survey Research Methods (5th ed.). Sage Publications. ISBN: 978-1452259000	Menard, S. (2002). Longitudinal Research (2nd ed.). Sage Publications. ISBN: 978-0761922292
Tên gọi khác	personal interview survey, in-person survey, PAPI survey, door-to-door survey	panel survey, repeated-measures survey, longitudinal panel study, wave survey
Liên quan	5	3
Tóm tắt	A face-to-face survey is a structured data collection method in which a trained interviewer meets respondents in person and administers a standardised questionnaire. The interviewer reads questions aloud, clarifies wording when permitted by protocol, and records answers — either on paper (PAPI) or a laptop/tablet (CAPI). This mode consistently achieves higher response rates and better data quality for complex or sensitive questionnaires than self-administered alternatives, and is the reference standard in large-scale population surveys.	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.