เปรียบเทียบวิธี

	การศึกษาแบบกลุ่ม (Cohort Study)	การสำรวจ
สาขาวิชา	ระบาดวิทยา	ระเบียบวิธีสำรวจ
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	Mid-20th century (formal epidemiological design codified ~1950s)	Late 19th century; systematic social-science use from 1940s
ผู้ริเริ่ม	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)	Francis Galton, Charles Booth, and early social statisticians; formalised by Paul Lazarsfeld in the 1940s
ประเภท	Observational longitudinal study design	Quantitative (primarily) or mixed-methods data-collection instrument
แหล่งต้นตำรับ	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641	Dillman, D. A., Smyth, J. D., & Christian, L. M. (2014). Internet, Phone, Mail, and Mixed-Mode Surveys: The Tailored Design Method (4th ed.). Wiley. ISBN: 978-1118456149
ชื่อเรียกอื่น	longitudinal study, follow-up study, panel study, incidence study	questionnaire survey, survey research, self-report survey, questionnaire study
ที่เกี่ยวข้อง	6	6
สรุป	A cohort study assembles a group of individuals who share a common starting point — typically freedom from the outcome of interest — and follows them over time to observe who develops the outcome. By comparing incidence rates between exposed and unexposed subgroups, researchers can estimate relative risk and absolute risk differences. Cohort studies are the gold-standard observational design for measuring disease incidence and establishing temporal relationships between exposure and outcome.	A survey is a systematic data-collection method in which a standardised set of questions is posed to a sample of respondents to measure attitudes, behaviours, demographics, or other constructs. Surveys can be administered via paper, telephone, online platforms, or face-to-face. They are among the most widely used instruments in social, behavioural, health, and educational research because they can reach large, geographically dispersed samples at relatively low cost.