Table 3 Follow-up methodologies in RCTs according to the date of beginning of patients enrollment
Date of beginning of patients enrollment | ||||||
|---|---|---|---|---|---|---|
Before 1998 | After 1998 | |||||
Follow-up approach | Follow-up approach | |||||
Minimal | Intensive | Minimal | Intensive | |||
No. (%) | No. (%) | P value | No. (%) | No. (%) | P value | |
Geographic location | ||||||
International | 7 (87) | 1 (13) | 5 (100) | - | 0.01 | |
North America (USA and Canada) | 3 (60) | 2 (40) | 4 (80) | 1 (20) | ||
Western Europe | 12 (37) | 20 (63) | 1 (16) | 5 (83) | ||
East Asia (Japan, Vietnam, China) | 1 (33) | 2 (67) | 0.07 | - | 2 (100) | |
Number of participating countries | ||||||
1 country | 13 (39) | 20 (60) | 3 (30) | 7 (70) | 0.01 | |
> 1 country | 10 (66) | 5 (33) | 0.08 | 7 (87) | 1 (87) | |
Number of participating centers | ||||||
≤ 50 | 11 (46) | 13 (54) | - | 5 (100.0) | 0.02 | |
> 50 | 6 (54) | 5 (46) | 0.63 | 4 (67) | 2 (33) | |
Industry sponsorship | ||||||
Yes | 9 (41) | 13 (59) | 9 (60) | 6 (40) | 0.40 | |
No | 14 (54) | 12 (46) | 0.37 | 1 (33) | 2 (67) | |
Number of enrolled patients | ||||||
≤ 1000 patients | 13 (45) | 16 (55) | 1 (20.0) | 4 (80.0) | 0.06 | |
> 1000 patients | 10 (53) | 9 (47) | 0.60 | 9 (69) | 4 (31) | |