Table 4. Risk of bias assessment for cohort studies using the New-Ottawa Scale (NOS).
| Number | Study | Selection | Comparability | Outcome | Total number of stars | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Represen-tativeness of exposed cohort | Selection of 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 | Assessment of outcome | Was follow-up long enough for outcomes to occur | Adequacy of follow-up of cohorts | |||
| 1 | Al-Mefty, 1985 [99] | * | * | * | NA | * | NA | NA | 4 | |
| 2 | Albright., 2005 [51] | * | * | * | * | NA | NA | NA | 4 | |
| 3 | Ali, 2013 [54] | * | * | * | NA | NA | NA | 3 | ||
| 4 | Ammirati, 1988 [71] | * | * | * | NA | * | NA | NA | 4 | |
| 5 | Anderson, 1989 [53] | * | * | * | * | NA | * | NA | NA | 5 |
| 6 | Ansari, 2016 [62] | * | * | * | * | NA | NA | NA | 4 | |
| 7 | Artero, 1984 [107] | * | * | * | * | NA | * | NA | NA | 5 |
| 8 | Ashkenazi, 1990 [82] | * | * | * | NA | * | NA | NA | 3 | |
| 9 | Bartlett, 1971 [35] | * | * | * | * | NA | NA | NA | 4 | |
| 10 | Behari, 2003 [81] | * | * | * | NA | * | NA | NA | 4 | |
| 11 | Bialer, 2012 [84] | * | * | * | * | NA | * | NA | NA | 5 |
| 12 | Boekhoff, 2019 [70] | * | * | * | * | NA | NA | NA | 4 | |
| 13 | Cai, 2019 [76] | * | * | * | NA | * | NA | NA | 4 | |
| 14 | Caldarelli, 2005 [90] | * | * | * | * | NA | * | NA | NA | 5 |
| 15 | Capatina, 2018 [106] | * | * | * | * | NA | * | NA | NA | 5 |
| 16 | Chamlin, 1955 [52] | * | * | * | * | NA | * | NA | NA | 5 |
| 17 | Chen, 2003 [6] | * | * | * | * | NA | * | NA | NA | 5 |
| 18 | Cherninkova, 1990 [102] | * | * | * | * | NA | * | NA | NA | 5 |
| 19 | d’Avella, 2019 [91] | * | * | * | * | NA | * | NA | NA | 5 |
| 20 | Drimtzias, 2014 [72] | * | * | * | * | NA | * | NA | NA | 5 |
| 21 | Erşahin, 2005 [101] | * | * | * | * | NA | * | NA | NA | 5 |
| 22 | Fisher, 1998 [43] | * | * | * | * | NA | * | NA | NA | 5 |
| 23 | Fouda, 2019 [63] | * | * | * | * | NA | * | NA | NA | 5 |
| 24 | Gautier, 2012 [73] | * | * | * | * | NA | * | NA | NA | 5 |
| 25 | Gerganov, 2014 [67] | * | * | * | NA | NA | NA | 3 | ||
| 26 | Goldenberg-Cohen, 2011 [83] | * | * | NA | * | NA | NA | 3 | ||
| 27 | Gonc, 2004 [31] | * | * | * | * | NA | * | NA | NA | 5 |
| 28 | Greenfield, 2015 [60] | * | * | * | * | NA | * | NA | NA | 5 |
| 29 | Haghighatkhah, 2010 [104] | * | * | NA | NA | NA | 2 | |||
| 30 | Hakuba, 1985 [86] | * | * | * | NA | * | NA | NA | 4 | |
| 31 | Hoff, 1972 [37] | * | * | * | * | NA | * | NA | NA | 5 |
| 32 | Hoffmann, 1977 [25] | * | * | * | * | NA | * | NA | NA | 5 |
| 33 | Hoffmann, 1992 [89] | * | * | * | * | NA | * | NA | NA | 5 |
| 34 | Hoffmann, 2015 [68] | * | * | * | * | NA | NA | NA | 4 | |
| 35 | Honegger, 1999 [26] | * | * | * | * | NA | NA | NA | 4 | |
| 36 | Hoogenhout, 1984 [93] | * | * | * | * | NA | NA | NA | 4 | |
| 37 | Im, 2002 [97] | * | * | * | * | NA | NA | NA | 4 | |
| 38 | Jane jr., 2010 [64] | * | * | * | * | NA | * | NA | NA | 5 |
| 39 | Jung, 2010 [98] | * | * | * | * | NA | * | NA | NA | 5 |
| 40 | Karavitaki, 2005 [48] | * | * | * | * | NA | * | NA | NA | 5 |
| 41 | Kennedy, 1975 [39] | * | * | * | * | NA | * | NA | NA | 5 |
| 42 | Kiran, 2008 [79] | * | * | * | NA | * | NA | NA | 4 | |
| 43 | Kramer, 1960 [38] | * | * | * | * | NA | * | NA | NA | 5 |
| 44 | Lee, 2008 [108] | * | * | * | NA | NA | NA | 3 | ||
| 45 | Lena, 2005 [24] | * | * | * | * | NA | * | NA | NA | 5 |
| 46 | Leng, 2012 [58] | * | * | * | * | NA | * | NA | NA | 5 |
| 47 | Merchant, 2002 [65] | * | * | * | * | NA | * | NA | NA | 5 |
| 48 | Mohd-Ilham, 2019 [7] | * | * | * | * | NA | * | NA | NA | 5 |
| 49 | Mottolese, 2001 [33] | * | * | * | * | NA | NA | NA | 4 | |
| 50 | Nielsen, 2013 [103] | * | * | * | * | NA | * | NA | NA | 5 |
| 51 | Ohmori, 2007 [28] | * | * | * | * | NA | NA | NA | 4 | |
| 52 | Ono, 1996 [87] | * | * | * | NA | * | NA | NA | 4 | |
| 53 | Pascual, 2018 [55] | * | * | * | * | NA | NA | NA | 4 | |
| 54 | Patel, 2017 [56] | * | * | * | * | NA | NA | NA | 4 | |
| 55 | Puget, 2007 [14] | * | * | * | * | * | NA | NA | 5 | |
| 56 | Qi, 2012 [77] | * | * | * | * | NA | NA | NA | 4 | |
| 57 | Quon, 2019 [57] | * | * | * | NA | * | NA | NA | 4 | |
| 58 | Rath, 2012 [96] | * | * | * | * | NA | * | NA | NA | 5 |
| 59 | Richmond, 1980 [61] | * | * | * | NA | * | NA | NA | 4 | |
| 60 | Salunke, 2016 [80] | * | * | NA | * | NA | NA | 3 | ||
| 61 | Sankhla, 2015 [27] | * | * | * | NA | NA | NA | 3 | ||
| 62 | Shammari, 2012 [100] | * | NA | NR | NA | 1 | ||||
| 63 | Shi, 2017 [78] | * | * | * | * | NA | * | NA | NA | 5 |
| 64 | Sogg, 1977 [109] | * | * | * | NA | * | NR | NA | 4 | |
| 65 | Stahnke, 1984 [29] | * | * | * | * | NA | * | NA | NA | 5 |
| 66 | Suharwardy, 1997 [9] | * | * | * | * | NA | * | NA | NA | 5 |
| 67 | Synowitz, 1977 [69] | * | * | * | * | NA | * | NA | NA | 5 |
| 68 | Tamasauskas, 2014 [105] | * | * | * | * | NA | * | NA | NA | 5 |
| 69 | Tan, 2017 [42] | * | * | * | * | * | * | NA | NA | 6 |
| 70 | Taphoorn, 2000 [94] | * | * | * | * | NA | * | NA | NA | 5 |
| 71 | Taylor, 2012 [74] | * | * | * | NA | NA | NA | 3 | ||
| 72 | Thomsett, 1980 [32] | * | * | * | * | NA | * | NA | NA | 5 |
| 73 | Tomita, 2005 [66] | * | * | * | * | NA | * | NA | NA | 5 |
| 74 | Villani, 1997 [92] | * | * | * | * | NA | * | NA | NA | 5 |
| 75 | Vries de, 2003 [85] | * | * | * | NA | NA | NA | 3 | ||
| 76 | Wan, 2018 [10] | * | * | * | * | NA | * | NA | NA | 5 |
| 77 | Weiss, 1989 [59] | * | * | * | * | NA | * | NA | NA | 5 |
| 78 | Wijnen, 2017 [95] | * | * | * | * | NA | * | NA | NA | 5 |
| 79 | Winkfield, 2011 [34] | * | * | * | * | NA | NA | NA | 4 | |
| 80 | Yamada, 2018 [88] | * | * | * | * | NA | * | NA | NA | 5 |
| 81 | Yano, 2016 [19] | * | * | * | * | NA | NA | NA | 4 | |
| 82 | Yu, 2015 [46] | * | * | * | NA | * | NA | NA | 4 | |
| 83 | Zhang, 2008 [30] | * | * | * | * | NA | NA | NA | 4 | |
| 84 | Zhou, 2009 [75] | * | * | * | NA | * | NA | NA | 4 | |
Studies in italics indicate studies retrieved by reference screening.
* The study met an item of the NOS.
NA: Not applicable, i.e. items do not apply to the research question and design of this review.