So sánh phương pháp

	Nghiên cứu sinh thái tiềm cứu	Nghiên cứu đoàn hệ tiền cứu
Lĩnh vực	Dịch tễ học	Dịch tễ học
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1950s–1970s (ecological epidemiology); prospective variant widely applied from 1980s onward	1950s (systematic application); conceptual roots earlier
Người khởi xướng	Ecological study design formalised in epidemiology mid-20th century; prospective variant established through environmental and chronic disease research	Richard Doll and Austin Bradford Hill (landmark application, 1951-1954); cohort methodology formalised by modern epidemiology textbooks
Loại	Observational epidemiological study design	Observational longitudinal study design
Công trình gốc	Morgenstern, H. (1998). Ecological studies. In K. J. Rothman & S. Greenland (Eds.), Modern Epidemiology (2nd ed., pp. 459–480). Lippincott-Raven.	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
Tên gọi khác	prospective ecologic study, prospective aggregate-level study, prospective group-level study, ecological cohort study	longitudinal cohort study, prospective follow-up study, incidence study, prospective observational cohort
Liên quan	4	6
Tóm tắt	A prospective ecological study is an observational epidemiological design in which groups — not individuals — serve as the unit of analysis, and exposure data are collected going forward in time before outcomes are measured. Investigators define geographically, politically, or socially bounded populations, characterise their aggregate exposures at baseline, then ascertain group-level outcomes (disease rates, mortality rates) at one or more later time points. Because exposure precedes outcome measurement, this design provides stronger temporal evidence than retrospective ecological studies.	A prospective cohort study assembles a group of participants who are free of the outcome of interest at baseline, measures their exposures, and then follows them forward in time to record who develops the outcome. By collecting exposure data before outcomes occur, it establishes a clear temporal sequence that supports causal inference — a major advantage over retrospective designs. It is the cornerstone observational method in epidemiology and clinical research.