เปรียบเทียบวิธี

	การทดลองทางคลินิกระยะที่ III แบบหลายศูนย์	การศึกษาเฟส 4
สาขาวิชา	ระบาดวิทยา	ระบาดวิทยา
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	1940s–1990s (formalized through ICH harmonization ~1990s)	Formalised 1970s–1990s (ICH E3 guideline 1994)
ผู้ริเริ่ม	Codified through ICH E9 guideline (1998) and decades of regulatory practice (FDA, EMA)	Regulatory agencies and pharmaceutical industry (ICH, FDA, EMA frameworks)
ประเภท	Confirmatory interventional study design	Post-marketing observational or interventional study
แหล่งต้นตำรับ	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	International Conference on Harmonisation (ICH). (1994). ICH Harmonised Tripartite Guideline: Structure and Content of Clinical Study Reports E3. ICH Secretariat.
ชื่อเรียกอื่น	Phase III multicenter RCT, confirmatory multicenter trial, Phase 3 multicenter study, pivotal multicenter trial	post-marketing surveillance study, post-approval study, Phase 4 study, PMS study
ที่เกี่ยวข้อง	6	5
สรุป	A multicenter Phase III clinical trial is the definitive confirmatory study that tests whether a new intervention produces a clinically meaningful benefit over a comparator in a large, representative patient population enrolled at two or more independent research sites. It is the primary evidence basis for regulatory approval by agencies such as the FDA and EMA, combining the statistical power of large samples with the external validity gained from geographic and demographic diversity across sites.	A Phase IV study is a post-marketing surveillance study conducted after a drug, device, or intervention has received regulatory approval. Its primary purpose is to monitor long-term safety, detect rare adverse events, assess effectiveness in routine clinical practice, and explore new indications or populations not adequately represented in earlier trials. Phase IV evidence accumulates continuously throughout a product's commercial life.