Table 1. Study Characteristics.
| Characteristic | Trials, No. (%) (N = 186) |
|---|---|
| Sponsor | |
| Commercial | 95 (51.1) |
| Noncommercial | 82 (44.1) |
| Unknown | 9 (4.8) |
| Type of study | |
| Parallel group | 170 (91.4) |
| Cluster | 11 (5.9) |
| Crossover | 5 (2.7) |
| Multicountry | 50 (26.9) |
| Countries included, median (IQR), No. | 7.5 (3-11) |
| Intervention | |
| Dialysis practice change | 41 (22.0) |
| Oral pharmaceutical | 39 (21.0) |
| Phosphate binder | 32 (17.2) |
| Erythropoietin-stimulating agent | 24 (12.9) |
| Injectable pharmaceutical | 19 (10.2) |
| Other | 13 (7.0) |
| Dietary | 6 (3.2) |
| Fistula or graft related | 5 (2.7) |
| Physical therapy | 3 (1.6) |
| Increased hours or frequency of dialysis | 2 (1.1) |
| Other surgical procedure or device | 2 (1.1) |
| Type of primary outcome | |
| Surrogate | 126 (67.7) |
| Clinical eventa | 48 (25.8) |
| Cardiovascular event(s) | 12 (6.5) |
| Mortality | 20 (10.8) |
| Complication of dialysis | 23 (12.4) |
| Other | 5 (2.7) |
| Patient reported | 10 (5.4) |
| Other | 2 (1.1) |
| Included modality | |
| Hemodialysis | 149 (80.1) |
| Both hemodialysis and peritoneal dialysis | 21 (11.3) |
| Peritoneal dialysis | 16 (8.6) |
| Incident participants only | 10 (5.4) |
| Primary outcome statistically significantb | 136 (73.1) |
| Participants, median (IQR), No. | 212 (149-339) |
| Sites, median (IQR), No. | 16 (5-42) |
| Planned duration of follow-up, median (IQR), mo | 7 (3-12) |
| Blinding | |
| Open-label | 119 (64.0) |
| Double-blind | 60 (32.3) |
| Single-blind | 7 (3.8) |
| Upper age limit specified | 35 (18.8) |
Abbreviation: IQR, interquartile range.
a
Subcategories are overlapping owing to coprimary or composite end points.
b
Based on author-specified criteria for significance. Achievement of noninferiority was considered significant where this was the stated primary outcome.