Table 5. Statistical Reporting in adjusted indirect comparisons [n/N(%)].
| Items | n/N | Journal impact factor (n = 37)* | Year of publication (n = 43)# | ||||
|---|---|---|---|---|---|---|---|
| Low (<5.00)(n = 29) | High (≥5.00)(n = 8) | P-value | Older studies(~2013) (n = 31) | Recent studies(2014~2015) (n = 12) | P-value | ||
| Was traditional meta-analysis conducted? (Yes) | 42/43(97.67) | 28/29(96.55) | 8/8(100.00) | 0.599 | 30/31(96.77) | 12/12(100.00) | 0.534 |
| Were summary measures reported? (Yes) | 41/43(97.62) | 26/29(89.66) | 8/8(100.00) | 0.976 | 29/31(93.55) | 12/12(100.00) | 0.373 |
| Planned methods of analysis in adjusted indirect comparisons: | |||||||
| What was the method used? | |||||||
| Bucher | 23/28(82.14) | 17/20(85.00) | 2/4(50.00) | 0.140 | 15/20(75.00) | 8/8(100.00) | 0.240 |
| Other methods | 5/28(17.86) | 3/20(15.00) | 2/4(50.00) | 0.123 | 5/20(25.00) | 0/8(0.00) | 0.125 |
| Not reported | 15/43(34.88) | 9/29(31.03) | 4/8(50.00) | 0.326 | 11/31(35.48) | 4/12(33.33) | 0.896 |
| Was the method presented or source cited? | |||||||
| Manuscript | 5/23(21.74) | 1/16(6.25) | 2/4(50.00) | 0.033 | 4/20(20.00) | 1/3(33.33) | 0.610 |
| Reference | 18/23(78.26) | 15/16(93.75) | 2/4(50.00) | 0.033 | 16/20(80.00) | 2/3(66.67) | 0.610 |
| Not provided | 20/43(46.51) | 13/29(44.83) | 4/8(50.00) | 0.798 | 11/31(35.48) | 9/12(75.00) | 0.021 |
| Was handling of multigroup trials reported? (Yes) | 2/43(4.65) | 0/29(0.00) | 1/8(12.50) | 0.057 | 2/31(6.45) | 0/12(0.00) | 0.373 |
| Was the similarity assessed? | 3/43(6.98) | 3/29(10.34) | 0/8(0.00) | 0.349 | 3/31(9.68) | 0/12(0.00) | 0.269 |
| Was the inconsistency assessed? | |||||||
| Not reported | 36/43(83.72) | 25/29(86.21) | 5/8(62.50) | 0.150 | 26/31(83.87) | 10/12(83.33) | 0.970 |
| Not application | 4/7(57.14) | 4/4(100.00) | 0/3(0.00) | 0.050 | 3/5(60.00) | 1/2(50.00) | 0.810 |
| Hypothesis test | 3/7(42.86) | 0/4(0.00) | 3/3(100.00) | 0.050 | 2/5(40.00) | 1/2(50.00) | 0.810 |
| Additional analyses: | |||||||
| Was a sensitivity analysis performed? | 5/43(11.63) | 1/29(3.45) | 3/8(37.50) | 0.007 | 3/31(9.68) | 2/12(16.67) | 0.526 |
| Was subgroup analysis or meta-regression performed? | 9/43(20.93) | 8/29(27.59) | 1/8(12.50) | 0.385 | 6/31(19.35) | 3/12(25.00) | 0.827 |
*6 studies published in journals with no associated impact factor.
#Based on the median division of number of included NMAs, December 31st 2013 is the cut-off point.