Table 2 Association between characteristics of articles and statistically significant results or conclusions that favor the test drug: Univariate logistic regression (n = 137).
| Â | Â | Results Favor Test Drug | Conclusions Favor Test Drug | ||||
|---|---|---|---|---|---|---|---|
Characteristic | Category | Favorable n/Total n (%) | OR (95% CI) | P | Favorable n/Total n (%) | OR (95% CI) | P |
Trial registration before publication | No | 44/83 (53) | 1.00 | Â | 55/83 (66) | 1.00 | Â |
| Â | Yes | 36/54 (67) | 1.77 (0.87-3.61) | 0.115 | 43/54 (80) | 1.99 (0.89-4.45) | 0.093 |
Year of publication | 1996-2002 | 16/29 (55) | 1.00 | Â | 21/29 (72) | 1.00 | Â |
| Â | 2003-2004 | 27/40 (68) | 1.69 (0.63-4.53) | 0.299 | 30/40 (75) | 1.14 (0.39-3.38) | 0.809 |
| Â | 2005-2006 | 18/33 (55) | 0.98 (0.36-2.66) | 0.961 | 20/33 (61) | 0.59 (0.20-1.71) | 0.328 |
| Â | 2007-2008 | 19/35 (54) | 0.97 (0.36-2.59) | 0.943 | 27/35 (77) | 1.29 (0.41-4.00) | 0.664 |
Impact Factor* | Quartile 1 (1.55-4.44) | 15/32 (47) | 1.00 | Â | 19/32 (59) | 1.00 | Â |
| Â | Quartile 2 (4.45-10.44) | 19/33 (58) | 1.54 (0.58-4.10) | 0.389 | 22/33 (67) | 1.37 (0.50-3.76) | 0.543 |
| Â | Quartile 3 (10.45-17.15) | 20/35 (57) | 1.51 (0.58-3.96) | 0.402 | 26/35(74) | 1.98 (0.70-5.57) | 0.197 |
| Â | Quartile 4 (17.16-52.59) | 21/27 (78) | 3.97 (1.27-12.43) | 0.018 | 24/27 (89) | 5.47 (1.36-22.01) | 0.017 |
Blinding | Stringent | 18/36 (50) | 1.00 | Â | 25/36 (69) | 1.00 | Â |
| Â | Not stringent | 62/101 (61) | 1.59 (0.74-3.42) | 0.236 | 73/101 (72) | 1.15 (0.50-2.64) | 0.747 |
Sample Size | Quartile 1 (6-122) | 10/34 (29) | 1.00 | Â | 19/34 (56) | 1.00 | Â |
| Â | Quartile 2 (123-352) | 22/34 (65) | 4.40 (1.59-12.19) | 0.004 | 24/34 (71) | 1.90 (0.70-5.16) | 0.211 |
| Â | Quartile 3 (353-772) | 22/35 (63) | 4.06 (1.48-11.12) | 0.006 | 26/35 (74) | 2.28 (0.83-6.30) | 0.112 |
| Â | Quartile 4 (773-8010) | 26/34 (76) | 7.8 (2.64-23.03) | <0.001 | 29/34 (85) | 4.58 (1.43-14.69) | 0.011 |
Primary efficacy outcome | Survival | 17/30 (57) | 1.00 | Â | 21/30 (70) | 1.00 | Â |
| Â | Surrogate | 63/107 (59) | 1.10 (0.48-2.48) | 0.828 | 77/107 (72) | 1.10 (0.45-2.67) | 0.833 |
Comparison group | Active comparator | 35/65 (54) | 1.00 | Â | 45/65 (69) | 1.00 | Â |
| Â | Placebo | 45/72 (63) | 0.70 (0.35-1.39) | 0.306 | 53/72 (74) | 0.81 (0.38-1.70) | 0.571 |
Sponsored | No | 14/28 (50) | 1.00 | Â | 15/28 (54) | 1.00 | Â |
| Â | Yes | 66/109 (61) | 1.54 (0.67-3.54) | 0.314 | 83/109 (76) | 2.77 (1.17-6.56) | 0.021 |