Table 2.
Newcastle-Ottawa Scale (cohort studies).
| References | Selection | Comparability | Outcome | Quality | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Representativeness of the exposed cohort | Selection of the non-exposed cohort | Ascertainment of exposure | Demonstration that outcome of interest was not present at start of study | Comparability of cohorts on the basis of the design or analysis (the most important factor) | Comparability of cohorts on the basis of the design or analysis (the second factor) | Assessment of outcome | Was follow-up long enough for outcomes to occur | Adequacy of follow up of cohorts | ||
| Axelrod et al. (33) | * | – | * | – | – | – | * | * | – | 4 |
| Bolliger et al. (19) | – | * | * | * | – | – | * | * | * | 6 |
| Wallaert et al. (34) | * | – | * | – | – | – | * | * | – | 4 |
| Bakker et al. (35) | – | – | * | – | – | – | * | * | – | 3 |
| Serio et al. (36) | * | * | * | – | * | – | * | * | – | 6 |
| Golinvaux et al. (15) | * | * | * | – | – | – | * | * | – | 5 |
| Qin et al. (37) | * | * | * | – | – | – | * | * | – | 5 |
| Haltmeier et al. (38) | * | * | * | – | * | * | * | * | – | 7 |
| Qin et al. (39) | * | * | * | – | – | – | * | * | – | 5 |
| Fu et al. (40) | * | * | * | – | – | – | * | * | – | 5 |
| Patterson et al. (41) | * | * | * | – | – | – | * | * | – | 5 |
| Phan et al. (42) | * | * | * | – | – | – | * | * | – | 5 |
| Webb et al. (43) | * | * | * | – | – | – | * | * | – | 5 |
| Di Capua et al. (44) | * | * | * | – | – | – | * | * | – | 5 |
| Stepan et al. (45) | * | * | * | – | – | – | * | * | – | 5 |
| Pothof et al. (46) | * | * | * | – | – | – | * | * | – | 5 |
| Traven et al. (16) | * | * | * | – | – | – | * | * | – | 5 |
| Gu et al. (22) | * | * | * | – | – | – | * | * | – | 5 |
| Leonard-Murali et al. (23) | * | * | * | – | – | * | * | * | – | 6 |
| Mamidi et al. (47) | * | * | * | – | * | * | * | * | – | 7 |
| Selemon et al. (48) | * | * | * | – | – | – | * | * | – | 5 |
| Kebaish et al. (49) | * | * | * | – | – | – | * | * | * | 6 |
*
The scale uses a star system, with a maximum of score of 9 stars, and includes 3 categories: selection, comparability, and outcome. Asterisk represents one point.