مقایسهٔ روش‌ها

	مطالعه کوهورت چندمرکزی	کارآزمایی بالینی تصادفی (RCT)
حوزه	اپیدمیولوژی	اپیدمیولوژی
خانواده	Process / pipeline	Process / pipeline
سال پیدایش	Mid-to-late 20th century (widespread adoption 1970s–1990s)	1948 (first rigorously conducted RCT — MRC streptomycin trial)
پدیدآور	Developed incrementally through large collaborative epidemiological projects (e.g., Framingham Heart Study consortium expansions, 1948 onward; EPIC study, 1992)	Austin Bradford Hill; MRC Streptomycin Trial team
نوع	Observational longitudinal study	Interventional experimental study
منبع بنیادین	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641	Friedman, L. M., Furberg, C. D., DeMets, D. L., Reboussin, D. M., & Granger, C. B. (2015). Fundamentals of Clinical Trials (5th ed.). Springer. ISBN: 978-3319185385
نام‌های دیگر	multisite cohort study, multi-centre cohort, collaborative cohort study, pooled cohort study	RCT, randomized controlled trial, randomised controlled trial, clinical randomized trial
مرتبط	6	6
خلاصه	A multicenter cohort study follows defined groups of participants at two or more geographically or institutionally distinct sites over time to estimate incidence, identify risk factors, and quantify associations between exposures and outcomes. By pooling data from multiple centers, it achieves statistical power and population diversity that single-site designs cannot match, making it the workhorse of large-scale epidemiological and clinical research.	A randomized clinical trial (RCT) is an experimental study design in which participants are randomly assigned to an intervention group or a control group, then followed prospectively to compare outcomes. Random allocation is the defining feature: it distributes known and unknown confounders across groups by chance, making the RCT the strongest individual study design for establishing causal efficacy of a treatment or intervention under controlled conditions.