TABLE 2.
Description of study-level characteristics of eligible RCTs1
| Total | RCT parallel | RCT crossover | |
|---|---|---|---|
| Publications | 157 (100.00) | 92 (58.6) | 65 (41.4) |
| Blinding | |||
| Double-blind | 95 (60.5) | 59 (64.1) | 36 (55.4) |
| Single-blind | 26 (16.6) | 10 (10.8) | 16 (24.6) |
| Not blinded | 17 (10.8) | 11 (12.0) | 6 (9.2) |
| Unclear | 19 (12.1) | 12 (13.0) | 7 (10.7) |
| Mean age | |||
| <50 y | 54 (34.4) | 28 (30.4) | 26 (40.0) |
| ≥50 y | 79 (50.3) | 43 (46.7) | 36 (55.4) |
| Baseline health | |||
| Healthy | 53 (33.8) | 23 (25.0) | 30 (46.2) |
| At risk of CVD | 86 (54.8) | 62 (67.4) | 24 (36.9) |
| Existing CVD | 8 (5.1) | 2 (2.2) | 6 (9.2) |
| Mixed | 10 (6.4) | 5 (5.4) | 5 (7.7) |
| Study region | |||
| Africa | 3 (1.9) | 2 (2.2) | 1 (1.5) |
| Asia | 20 (12.7) | 17 (18.5) | 3 (4.6) |
| Australia | 7 (4.5) | 4 (4.3) | 3 (4.6) |
| Eastern Europe | 6 (3.8) | 4 (4.3) | 2 (3.1) |
| Western Europe | 60 (38.2) | 24 (26.1) | 36 (55.4) |
| Middle East | 12 (7.6) | 12 (13.0) | 0 (0.0) |
| North America | 47 (29.9) | 27 (29.3) | 20 (30.8) |
| South America | 2 (1.3) | 2 (2.2) | 0 (0.0) |
| Diabetes | |||
| 100% | 20 (12.7) | 17 (18.5) | 3 (4.6) |
| None | 87 (55.4) | 38 (41.3) | 49 (75.4) |
| Mixed | 16 (10.2) | 8 (8.7) | 8 (12.3) |
| Not reported | 34 (21.7) | 29 (31.5) | 5 (7.7) |
| Hypertension | |||
| 100% | 14 (8.9) | 6 (6.5) | 8 (12.3) |
| None | 50 (31.8) | 20 (21.7) | 30 (46.2) |
| Mixed | 22 (14.0) | 13 (14.1) | 9 (13.8) |
| Not reported | 71 (45.2) | 53 (57.6) | 18 (27.7) |
| Hypercholesterolemia | |||
| 100% | 9 (5.7) | 7 (7.6) | 2 (3.1) |
| None | 37 (23.5) | 12 (13.0) | 25 (38.5) |
| Mixed | 13 (8.3) | 8 (8.7) | 5 (7.7) |
| Not reported | 98 (62.4) | 65 (70.6) | 33 (50.7) |
| CVD | |||
| 100% | 9 (6.0) | 2 (2.2) | 7 (10.8) |
| None | 91 (60.3) | 52 (56.5) | 45 (69.2) |
| Mixed | 2 (1.3) | 1 (1.1) | 1 (1.5) |
| Not reported | 49 (32.4) | 37 (41.6) | 12 (18.5) |
| Intervention | |||
| Cocoa | 50 (31.9) | 24 (26.1) | 26 (40.0) |
| Extract | 26 (16.5) | 20 (21.7) | 6 (9.2) |
| Fruit | 40 (25.5) | 21 (22.8) | 19 (29.2) |
| Pure form | 5 (3.2) | 2 (2.2) | 3 (4.6) |
| Tea | 27 (17.2) | 20 (21.7) | 7 (10.7) |
| Wine | 9 (5.7) | 5 (5.4) | 4 (6.2) |
1
Values are numbers/frequencies (percentages) of study-level variables that represent the reporting characteristics of RCTs. CVD, cardiovascular disease; RCT, randomized controlled trial.