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What is The gold standard for diagnosis of gastroesophageal reflux disease (GERD) is: and explain in detail?
Barium swallow- IOC for diagnosis of Hiatus hernia and Zenker's diveicula Endoscopy + Biopsy- IOC for diagnosis of Barret's esophagus 24 hours PH monitoring- Gold standard Investigation for GERD Esophageal manometry- IOC for diagnosis of motility disorders of esophagus like Achalasia cardia, Diffuse esophageal spasm and Nut cracker's esophagus.