Table 1.
Baseline Characteristics for Studies Included in Meta‐Analysis
| Disease | Number of Data Sets | Region | Data source | Median Duration of Study Period (Years) | Total Sample Size | Quality Assessment | Mean Number of Potential Confounders in Analysis | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| North America | Europe and Australia | Others | Clinical Registry | Administrative Data | 7 to 9a | 4 to 6a | |||||
| Myocardial infarction | 56 | 22 | 24 | 10 | 37 | 19 | 5 (0.75–10) | 5 085 950 | 55 | 1 | 6 (0–11) |
| Stroke | 32 | 14 | 10 | 8 | 14 | 18 | 4 (1–18) | 1 865 127 | 30 | 2 | 6 (0–11) |
| Gastrointestinal bleeding | 17 | 9 | 5 | 3 | 5 | 12 | 2 (1–12) | 1 102 795 | 17 | 0 | 3 (0–5) |
| COPD | 11 | 6 | 5 | 0 | 0 | 11 | 1 (1–17) | 862 610 | 11 | 0 | 4 (2–6) |
| Neonatal mortality | 10 | 8 | 2 | 0 | 2 | 8 | 3.5 (1–13) | 7 493 579 | 6 | 4 | 3 (0–5) |
| Arrhythmia and cardiac arrest | 10 | 6 | 3 | 1 | 4 | 6 | 5 (1–10) | 467 660 | 9 | 1 | 3 (0–5) |
| Pneumonia | 9 | 5 | 2 | 2 | 1 | 8 | 4 (1–11) | 1 084 796 | 8 | 1 | 3 (2–4) |
| Pulmonary embolism | 8 | 5 | 3 | 0 | 8 | 0 | 4.5 (1–10) | 1 258 258 | 6 | 2 | 4 (0–8) |
| Renal failure | 8 | 6 | 2 | 0 | 0 | 8 | 5.5 (1–9) | 4 288 095 | 8 | 0 | 4 (3–5) |
| Intracerebral hemorrhage | 8 | 6 | 1 | 1 | 1 | 7 | 1.5 (1–9) | 64 551 | 7 | 1 | 3 (0–6) |
| Heart failure | 7 | 4 | 2 | 1 | 1 | 6 | 3 (1–9) | 399 010 | 7 | 0 | 4 (1–7) |
| Malignant neoplasm of genitourinary organs | 7 | 0 | 7 | 0 | 0 | 7 | 9 (1–11) | 558 898 | 7 | 0 | 3 (2–4) |
| Aortic aneurysm | 6 | 0 | 4 | 2 | 0 | 6 | 1.5 (1–10) | 36 214 | 6 | 0 | 4 (3–5) |
| Hip fracture | 6 | 2 | 4 | 0 | 3 | 3 | 3 (1–9) | 127 461 | 6 | 0 | 3 (0–6) |
| Bloodstream infections | 6 | 5 | 1 | 0 | 2 | 4 | 4 (1–9) | 191 701 | 6 | 0 | 3 (2–5) |
| Trauma | 5 | 5 | 0 | 0 | 0 | 5 | 4 (1–8) | 131 469 | 4 | 1 | 3 (0–5) |
| Leukemia | 5 | 3 | 2 | 0 | 0 | 5 | 2 (1–9) | 17 717 | 5 | 0 | 4 (3–4) |
| Respiratory neoplasm | 5 | 3 | 2 | 0 | 0 | 5 | 7 (1–9) | 65 909 | 5 | 0 | 4 (3–4) |
| Subarachnoid hemorrhage | 4 | 3 | 0 | 1 | 0 | 4 | 2 (1–9) | 14 015 | 4 | 0 | 5 (3–6) |
| Peptic ulcer | 4 | 4 | 0 | 0 | 0 | 4 | 5 (1–9) | 46 087 | 4 | 0 | 4 (3–4) |
| Breast cancer | 4 | 2 | 2 | 0 | 0 | 4 | 4 (1–9) | 13 306 | 4 | 0 | 4 (3–4) |
| Colorectal cancer | 4 | 3 | 1 | 0 | 0 | 4 | 5 (1–9) | 28 307 | 4 | 0 | 4 (3–4) |
| Intestinal obstruction | 4 | 3 | 1 | 0 | 0 | 4 | 4 (1–9) | 79 252 | 4 | 0 | 2 (0–4) |
| Traumatic brain injury | 3 | 3 | 0 | 0 | 0 | 3 | 2 (1–9) | 45 853 | 3 | 0 | 4 (3–5) |
| Diverticulosis | 3 | 3 | 0 | 0 | 0 | 3 | 6 (1–9) | 67 960 | 3 | 0 | 6 (3–9) |
| Pancreatic cancer | 3 | 2 | 1 | 0 | 0 | 3 | 1 (1–9) | 11 755 | 3 | 0 | 4 (3–4) |
| Lymphoma | 3 | 2 | 1 | 0 | 0 | 3 | 1 (1–9) | 15 175 | 3 | 0 | 4 (3–4) |
| Aspiration pneumonia | 3 | 2 | 1 | 0 | 0 | 3 | 1 (1–9) | 26 964 | 3 | 0 | 4 (3–4) |
COPD indicates chronic obstructive pulmonary disease.
a
Study quality was assessed using the Newcastle–Ottawa Scale.