قارن الطرق

	الدراسة الوبائية المقطعية	دراسة الأتراب
المجال	علم الأوبئة	علم الأوبئة
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1960s (formal codification); widely practiced since mid-20th century	Mid-20th century (formal epidemiological design codified ~1950s)
صاحب الطريقة	Classical epidemiology tradition; systematized by Brian MacMahon and Thomas Pugh (1960s)	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
النوع	Observational, descriptive/analytic epidemiological design	Observational longitudinal study design
المصدر التأسيسي	Kelsey, J. L., Whittemore, A. S., Evans, A. S., & Thompson, W. D. (1996). Methods in Observational Epidemiology (2nd ed.). Oxford University Press. ISBN: 978-0195080407	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
الأسماء البديلة	prevalence study, cross-sectional survey, transversal study, cross-sectional design	longitudinal study, follow-up study, panel study, incidence study
ذات صلة	6	6
الملخص	A cross-sectional epidemiological study measures the exposure(s) and outcome(s) of interest simultaneously in a defined population at a single point in time (or over a short period). Because there is no follow-up, it is the most efficient observational design for estimating disease prevalence and for generating hypotheses about associations between risk factors and health outcomes.	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.