Table 3. Distribution of the level of evidence and strength of recommendation.
| Guideline | Level of evidence, No. (%) | Strength of recommendation, No. (%) | ||||||
|---|---|---|---|---|---|---|---|---|
| A | B | C | D | I | II | UG | ||
| Dodek 2004 (19) | 0 (0) | 36 (81.8) | 5 (11.4) | 3 (6.8) | 10 (62.5) | 0 (0) | 6 (37.5) | |
| Muscedere 2008a (20) | 0 (0) | 31 (100.0) | 0 (0) | 0 (0) | 8 (100.0) | 0 (0) | 0 (0) | |
| Muscedere 2008b (21) | 4 (6.5) | 58 (93.5) | 0 (0) | 0 (0) | 9 (40.9) | 4 (18.2) | 9 (40.9) | |
| Masterton 2008 (22) | 20 (16.8) | 25 (21.0) | 13 (10.9) | 61 (51.3) | – | – | – | |
| Rotstein 2008 (23) | 10 (22.2) | 21 (46.7) | 4 (8.9) | 10 (22.2) | 15 (33.3) | 17 (37.8) | 13 (28.9) | |
| Morrow 2009 (24) | 3 (18.7) | 5 (31.3) | 0 (0) | 8 (50.0) | – | – | – | |
| Gupta 2012 (25) | 16 (35.6) | 17 (37.8) | 5 (11.1) | 7 (15.5) | 34 (89.5) | 4 (10.5) | 0 (0) | |
| Li 2013 (3) | 1 (3.2) | 15 (48.4) | 15 (48.4) | 0 (0) | 17 (54.8) | 14 (45.2) | 0 (0) | |
| Klompas 2014 (26) | 8 (12.7) | 19 (30.1) | 34 (54.0) | 2 (3.2) | 9 (37.5) | 15 (62.5) | 0 (0) | |
| Kalil 2016 (27) | 0 (0) | 7 (15.6) | 18 (40.0) | 20 (44.4) | 19 (42.2) | 26 (57.8) | 0 (0) | |
| Mikasa 2016 (28) | 3 (37.5) | 5 (62.5) | 0 (0) | 0 (0) | 2 (25.0) | 5 (62.5) | 1 (12.5) | |
| Torres 2017 (29) | 0 (0) | 4 (36.4) | 6 (54.5) | 1 (9.1) | 9 (56.3) | 6 (37.5) | 1 (6.2) | |
| Qu 2018 (1) | 11 (28.9) | 15 (39.5) | 6 (15.8) | 6 (15.8) | 16 (42.1) | 13 (34.2) | 9 (23.7) | |
| Total | 76 (13.6) | 258 (46.2) | 106 (19.0) | 118 (21.2) | 148 (50.9) | 104 (35.7) | 39 (13.4) | |