Table 1

Characteristics of randomised controlled trials of H. pylori eradication therapy versus placebo or no treatment in the prevention of gastric cancer in healthy individuals

StudyLocationMethod used to confirm presence of H. pylori Sample size (no. receiving H. pylori eradication therapy)Characteristics of participantsProportion with pre-neoplastic lesions* at baseline H. pylori eradication therapy regimen usedEradication rate†Last point of follow-upMethod of ascertainment of gastric cancer cases
Correa 2000 and Correa 2001 22 23 Two communities in Narino Province, Colombia.Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy.852 (437)Mean age 51.1 years (range 29–69 years), 46.1% male.100%Bismuth subsalicylate 262 mg, amoxicillin 500 mg and metronidazole 375 mg t.i.d.‡ for 2 weeks.58.0%6 years.Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy at 6 years.
Leung 2004 and Zhou 2014 30 31 Eleven villages in Yantai County, Shandong Province, China.Histological examination of, and rapid urease testing using, gastric biopsies obtained at upper gastrointestinal endoscopy.587 (295)31
552 (276) Zhou 201430 		Mean age 52.0 years (range 35–75 years), 47.8% male.33.7%Omeprazole 20 mg, amoxicillin 1 g and clarithromycin 500 mg b.i.d.§ for 1 week.55.6%5 years in Leung,
10 years in Zhou.		Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy at 2, 5, 8 and 10 years.
Wong 2004 25 Seven villages in Changle County, Fujian Province, China.Histological examination of, and rapid urease testing using, gastric biopsies obtained at upper gastrointestinal endoscopy.1630 (817)Mean age 42.2 years (range 35–65 years), 54.0% male.37.7%Omeprazole 20 mg, co-amoxiclav 750 mg and metronidazole 400 mg b.i.d. for 2 weeks.83.7%7.5 years.Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy at 7.5 years or, if diagnosed before 7.5 years, review of clinical records and pathology specimens by three blinded clinicians.
Saito 2005 24 145 centres in Japan.Not reported.692 (379)Mean age not reported (range 20–59 years), proportion male not reported.Not reported.Lansoprazole 30 mg, amoxicillin 1.5 g and clarithromycin 400 mg o.d.¶ for 1 week.74.4%≥4 years.Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy at ≥4 years.
Ma 2012 and Li 2019 27 28 Thirteen villages in Linqu County, Shandong Province, China.Serological testing.2258 (1130)Mean age 46.8 years (range 35–64 years), 50.0% male.64.0%Omeprazole 20 mg and amoxicillin 1 g b.i.d. for 2 weeks.73.2%22.3 years.Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy, or from clinical, laboratory or pathological data.
Wong 2012 26 Twelve villages in Linqu County, Shandong Province, China.Carbon-urea breath testing.513 (255)Mean age 53.0 years (range 35–64 years), 46.4% male.100%Omeprazole 20 mg, amoxicillin 1 g and clarithromycin 500 mg b.i.d. for 1 week.63.5%5 years.Histological examination of gastric biopsies obtained at upper gastrointestinal endoscopy at 5 years.
Choi 2020 29 One hospital in Goyang, South Korea.Histological examination of, and rapid urease testing using, gastric biopsies obtained at upper gastrointestinal endoscopy.1826 (912)Mean age 48.8 years (range 40–65 years), 49.5% male.Not reported.Lansoprazole 30 mg, amoxicillin
1 g and clarithromycin 500 mg b.i.d. for 1 week		60.4%9.2 years.Access to the Korean National Cancer Incidence Database to confirm all cases of gastric cancer diagnosed by endoscopic surveillance during the trial.

  • *Defined as gastric atrophy, intestinal metaplasia or dysplasia.

  • †True intention-to-treat analysis, with all drop-outs assumed to have failed eradication therapy.

  • ‡t.i.d., three times per day.

  • §b.i.d., two times per day.

  • ¶o.d., one time per day.

  • H. pylori, Helicobacter pylori.