เปรียบเทียบวิธี

	การศึกษาเฟส 4	การทดลองทางคลินิกระยะที่ 3
สาขาวิชา	ระบาดวิทยา	ระบาดวิทยา
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	Formalised 1970s–1990s (ICH E3 guideline 1994)	1962 (Kefauver-Harris Amendment formalised phased drug development)
ผู้ริเริ่ม	Regulatory agencies and pharmaceutical industry (ICH, FDA, EMA frameworks)	FDA regulatory framework / ICH guidelines
ประเภท	Post-marketing observational or interventional study	Confirmatory randomised controlled trial
แหล่งต้นตำรับ	International Conference on Harmonisation (ICH). (1994). ICH Harmonised Tripartite Guideline: Structure and Content of Clinical Study Reports E3. ICH Secretariat.	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
ชื่อเรียกอื่น	post-marketing surveillance study, post-approval study, Phase 4 study, PMS study	Phase 3 trial, confirmatory trial, pivotal trial, Phase III RCT
ที่เกี่ยวข้อง	5	6
สรุป	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.	A Phase III clinical trial is a large-scale, confirmatory randomised controlled trial designed to establish the efficacy and safety of an intervention in the target patient population before regulatory submission. It builds on the signal identified in Phase II, tests the intervention at its proposed dose under controlled conditions, and provides the primary evidence base for marketing authorisation or guideline adoption.