| Included Studies | Country | Type of Study | Research Object | Dose (mg) | Tracking (year) | Average age (years) | Sample Size | Interventions | Outcome indicators | Literature quality evaluation | ||
| Intervention Control | Intervention | Control | ||||||||||
| Peto et al. 1988 [8] | UK | RCT | Healthy male doctor | 500 or 300 | 5.6 | 63.6 | 3429 | 1710 | Take a daily aspirin | Not taking | ①②③⑤⑦ | B |
| PHS 1989 [9] | US | RCT | Male doctors between the ages of 40and 84 | 325 | 5 | 53.8 | 11,037 | 11,034 | Take aspirin every other day | Take a placebo every other day | ①②③⑤⑥⑦ | B |
| Lindblad et al. 1993 [10] | Sweden | RCT | Patients undergoing carotid endarterectomy | 75 | 0.5 | 66 | 117 | 115 | Take a daily aspirin | Take a placebo daily | ①④⑥ | B |
| TPT 1998 [11] | UK | RCT | Men aged 45 to 69 years at high risk of ischemic heart disease | 75 | 6.8 | 57.5 | 1268 | 1272 | Take a daily aspirin | Take warfarin or a placebo daily | ①②③⑤⑥⑦ | A |
| Hansson et al. 1998 [12] | 26 countries in North and south Europe, US, Asia | RCT | Patients aged 50 to 80 years with hypertension | 75 | 3.8 | 61.5 | 9399 | 9391 | Take a daily aspirin | Take a placebo daily | ①②③⑥⑦ | B |
| Meade et al. 2000 [13] | UK | RCT | Men between the ages of 45 and 69 with an increased risk of coronary heart disease | 75 | 1 | 57.5 | 8105 | 8071 | Take a daily aspirin | Take a placebo daily | ①⑦ | B |
| Roncaglioni 2001 [14] | Italian | RCT | Patients with cardiovascular risk factors | 100 | 3.6 | 64.4 | 2226 | 2269 | Take a daily aspirin | Not taking | ①②③⑤⑥⑦ | B |
| Sacco et al. 2003 [15] | Italian | RCT | Diabetic patients aged ≥ 50 years | 100 | 3.7 | 64.2 | 519 | 512 | Take a daily aspirin | Not taking | ①④⑤⑦ | B |
| Cleland et al. 2004 [16] | UK, US | RCT | Heart failure patients | 300 | 2.3 | 63.5 | 91 | 89 | Take a daily aspirin | Not taking | ①⑤⑦ | B |
| Ridker et al. 2005 [17] | US | RCT | Healthy female specialist aged ≥ 45 years | 100 | 10.1 | 54.6 | 19,934 | 19,942 | Take aspirin every other day | Take a placebo every other day | ①②③④⑤⑥⑦ | B |
| DPC 2006 [18] | China | RCT | Hypertensive patients aged 40 - 75 years | 50 or 100 | 3.2 | 60.27 | 1151 | 1029 | Take a daily aspirin | Not taking | ①②③⑤⑦ | B |
| Ogawa et al. 2008 [19] | Japan | RCT | Diabetic patients aged 30 - 85 | 81 or 100 | 4.37 | 64.5 | 1262 | 1277 | Take a daily aspirin | Not taking | ①②③⑤⑥⑦ | B |
| Belch et al. 2008 [20] | UK | RCT | Diabetic patients aged ≥ 40 years | 100 | 6.7 | 60.3 | 638 | 638 | Take a daily aspirin | Take a placebo daily | ①②③④⑤⑥⑦ | A |
| Fowkes et al. 2010 [21] | UK | RCT | Age 50 - 75 years old and ABPI ≤ 0.95 | 100 | 8.2 | 62 | 1675 | 1675 | Take a daily aspirin | Take a placebo daily | ①②③④⑤⑥⑦ | A |
| Kurth et al. 2011 [22] | US | RCT | Women aged ≥ 45 years | 100 | 2.7 | 54.8 | 19,869 | 19,888 | Take aspirin every other day | Take a placebo every other day | ①②③④⑤⑦ | B |
| Ikeda et al. 2014 [23] | Japan | RCT | Patients aged 60 to 85 with hypertension, dyslipidemia or diabetes | 100 | 5 | 70.5 | 7220 | 7244 | Take a daily aspirin | Not taking | ①②③④⑤⑥⑦ | B |
| McNeil et al. 2018 [24] | Australia, US | RCT | People aged 70 or older | 100 | 4.7 | 74 | 9525 | 9589 | Take a daily aspirin | Take a placebo daily | ①②③⑤⑥⑦ | A |
| Gaziano et al. 2018 [25] | Germany, Italy, Ireland, Poland, Spain, US and UK | RCT | Patients with cardiovascular risk factors | 100 | 5 | 63.9 | 6270 | 6276 | Take a daily aspirin | Take a placebo daily | ①③④⑤⑥⑦ | A |
| ASCEND et al. 2018 [26] | US | RCT | Patients aged ≥ 40 years with diabetes | 100 | 7.4 | 63.2 | 7740 | 7740 | Take a daily aspirin | Take a placebo daily | ①②③④⑤⑥⑦ | A |