Table 1.
Characteristics of included studies.
| Study ID | Area | Study design | Sample size | Average age (years) | Gender ratio | Quality evaluation |
|---|---|---|---|---|---|---|
| Li [10] | Jiangxi | CSS | 398 | 75.42 ± 8.65 | 206/192 | 5 |
| Zhong and Xue [11] | Guangdong | CSS | 50 | 62.99 ± 3.49 | 25/25 | 6 |
| Liu et al. [12] | Henan | CSS | 109 | 57.94 ± 8.69 | 58/51 | 4 |
| Zhang et al. [13] | Shanghai | CSS | 120 | 56.88 ± 2.42 | 65/55 | 4 |
| Wu et al. [14] | Ningxia | CSS | 100 | 41.6 ± 4.5 | 68/32 | 5 |
| Wang et al. [15] | Shanghai | CSS | 112 | 55.8 ± 6.2 | 54/58 | 5 |
| Shen et al. [16] | Shanghai | CSS | 395 | 73.81 | 172/223 | 4 |
| Lin et al. [17] | Guangdong | CSS | 500 | 61.2 ± 5.3 | 258/242 | 6 |
| Li et al. [18] | Guizhou | CSS | 663 | 59.12 ± 6.57 | 411/252 | 3 |
| Hang et al. [19] | Guangdong | CSS | 250 | 71.01 ± 5.82 | 133/117 | 4 |
| Guan [20] | Jiangsu | CSS | 200 | U | 105/95 | 3 |
| Guan [21] | Sichuan | CSS | 195 | 69.36 ± 3.41 | 109/86 | 7 |
| Zhang et al. [22] | Zhejiang | CCS | 1315 | U | 890/425 | 6 |
| Zhou [23] | Fujian | CCS | 285 | 56.98 ± 6.75 | U | 5 |
| Wei and Yang [24] | Guangdong | CSS | 300 | U | U | 5 |
| Wang [25] | Neimongol | CSS | 270 | 66.8 ± 10.5 | 136/134 | 6 |
| Lin et al. [26] | Beijing | CSS | 122 | U | U | 4 |
| Li et al. [27] | Beijing | CSS | 119 | U | 71/48 | 5 |
| Lang [28] | Heilongjiang | CSS | 100 | 75.12 ± 6.34 | 56/44 | 7 |
| Jiang et al. [29] | Shanghai | CSS | 700 | 60.14 ± 4.55 | 350/350 | 5 |
| Hu et al. [30] | Tianjin | CSS | 200 | 61.32 ± 8.24 | 96/104 | 5 |
| Gao et al. [31] | Shandong | CSS | 75 | 69.92 | 33/42 | 4 |
| Chen et al. [32] | Zhejiang | CSS | 700 | 74.1 ± 13.1 | 242/458 | 5 |
| Zhou et al. [33] | Shanghai | CSS | 442 | U | 187/255 | 7 |
| Wang [34] | Shandong | CSS | 436 | 58.12 ± 9.63 | 255/181 | 7 |
| Shen et al. [35] | Beijing | CCS | 461 | 70.68 ± 10.41 | 202/259 | 6 |
| Shen et al. [36] | Beijing | CSS | 333 | 57.80 ± 10.91 | 133/200 | 6 |
| Qiu [37] | Xinjiang | CSS | 141 | 61.89 ± 11.37 | 86/55 | 5 |
| Lv [38] | Tianjin | CSS | 1003 | U | U | 7 |
| Liu et al. [39] | Jiangxi | CSS | 208 | 52.1 ± 3.4 | 107/91 | 5 |
| Li [40] | Beijing | CSS | 60 | U | 31/29 | 4 |
| Jing et al. [41] | Beijing | CSS | 160 | 56.35 ± 12.82 | 74/86 | 4 |
| Jing [42] | Guangxi | CSS | 297 | 57.59 ± 11.12 | 176/121 | 5 |
| Huang [43] | Guangdong | CSS | 497 | 67.94 ± 8.64 | 200/297 | 4 |
| Huang et al. [44] | Guangdong | CSS | 367 | 67.57 ± 8.77 | 137/230 | 4 |
| Huang et al. [45] | Zhejiang | CSS | 630 | U | 236/394 | 4 |
| Zhu et al. [46] | Nationwide | CSS | 412 | 52.54 ± 13.92 | U | 7 |
| Feng [47] | Jiangsu | CSS | 200 | 61.4 | 103/97 | 7 |
| Zou and Wang [48] | Sichuan | CSS | 320 | 52.11 ± 11.32 | 167/153 | 4 |
| Zhu et al. [49] | Beijing | CSS | 136 | U | U | 4 |
| Xue et al. [50] | Shanghai | CCS | 879 | U | 425/454 | 5 |
| Xu and Liu [51] | Shanxi | CSS | 251 | 59.666 | 114/133 | 4 |
| Xie et al. [52] | Henan | CSS | 426 | U | 258/198 | 5 |
| Wang et al. [53] | Guangdong | CSS | 112 | 86.61 ± 13.39 | 45/67 | 5 |
| Wang et al. [54] | Jiangsu | CSS | 300 | U | 144/156 | 6 |
| Wang [55] | Sichuan | CSS | 57 | 39.04 ± 12.09 | 10/17 | 7 |
| Ren et al. [56] | Shandong | CSS | 151 | 63.8 | 83/68 | 6 |
| Li [57] | Guangdong | CSS | 120 | 51.9 ± 4.7 | 68/52 | 5 |
| Li et al. [58] | Guangxi | CSS | 302 | 65.60 ± 10.96 | 130/172 | 6 |
| Huang [59] | Malaysia | CSS | 68 | 64.16 ± 10.03 | 30/38 | 5 |
| Hua et al. [60] | Shanghai | CSS | 931 | 73.45 ± 7.37 | 353/578 | 4 |
| Zou and Wang [61] | Beijing | CSS | 296 | 49.70 ± 12.28 | 173/123 | 4 |
| Zhao [62] | Inner Mongolia | CCS | 139 | U | 84/55 | 7 |
| Zhang [63] | Henan | CSS | 90 | 40 | 71/19 | 5 |
| Yu [64] | Liaoning | CSS | 372 | 60.9 l ± 11.557 | 173/199 | 6 |
| Yang [65] | Shandong | CSS | 192 | 63.4 ± 8.0 | 80/112 | 7 |
| Xiang and Qian [66] | Jiangsu | CSS | 835 | 63.4 | 343/492 | 5 |
| Wu and Hao [67] | Shanxi | CSS | 354 | U | 196/158 | 5 |
| Wu et al. [68] | Fujian | CSS | 476 | U | 188/288 | 4 |
| Wei et al. [69] | Shanghai | CSS | 400 | 59.8 ± 11.6 | 211/189 | 6 |
| Wang et al. [70] | Guangdong | CSS | 320 | 47.2 | 175/145 | 5 |
| Lu [71] | Shanghai | CSS | 1420 | 69.2 | 574/846 | 3 |
| Liu et al. [72] | Tianjin | CSS | 200 | U | U | 4 |
| Li [73] | Guangdong | CCS | 483 | 42.03 ± 12.68 | 263/220 | 6 |
| Li [74] | Fujian | CSS | 250 | 70.12 ± 11.92 | 204/261 | 5 |
| Hu et al. [75] | Jiangxi | CSS | 500 | 57.1 ± 11.4 | 188/312 | 6 |
| Chen and Zhou [76] | Zhejiang | CSS | 119 | 57.6 | 65/54 | 6 |
| Xiao et al. [77] | Guangdong | CSS | 300 | 65.6 ± 12.6 | 160/140 | 5 |
| Zhu et al. [78] | Shandong | CSS | 135 | 55.69 ± 9.87 | 56/79 | 6 |
| Yang and Wang [79] | Yunnan | CSS | 427 | U | U | 6 |
| Xiang and Ran [80] | Jiangsu | CSS | 270 | U | 116/154 | 5 |
| Xiang [81] | Jiangsu | CSS | 478 | 63.1 ± 9.1 | 201/277 | 5 |
| Wang et al. [82] | Beijing | CSS | 213 | 56.55 ± 12.14 | 99/104 | 6 |
| Li et al. [83] | Zhejiang | CSS | 300 | 56.57 ± 7.91 | 152/148 | 5 |
| Chen et al. [84] | Henan | CSS | 300 | 52.12 ± 12.19 | 152/148 | 5 |
| Zheng and Jian [85] | Guangdong | CCS | 89 | U | 54/35 | 6 |
| Wu et al.[86] | Guangdong | CSS | 147 | U | U | 6 |
| Tang [87] | Guangxi | CSS | 200 | 52.78 ± 6.62 | 99/101 | 3 |
| Ma [88] | Guangdong | CSS | 48 | 56.9 ± 6.7 | 35/13 | 4 |
| Liu [89] | Guangdong | CSS | 98 | 56.6 ± 4.8 | 55/43 | 6 |
| Li et al. [90] | Guangdong | CSS | 74 | 62.6 | 39/35 | 5 |
| Zhang et al. [91] | Hong Kong | CSS | 239 | 59 ± 10.33 | 119/120 | 5 |
| Han [92] | Beijing | CSS | 206 | 65 ± 12 | 91/115 | 6 |
| Han et al. [93] | Beijing | CSS | 52 | 58.14 ± 8.2 | 41/11 | 4 |
| Zhang [94] | Fujian | CSS | 534 | 57.67 ± 11.17 | 258/276 | 5 |
| Yan et al. [95] | Henan | CSS | 571 | 51.69 ± 8.81 | 284/287 | 6 |
| Cui [96] | Shanxi | CSS | 476 | U | 188/288 | 4 |
CSS, cross-sectional study; CCS, case-control study; U, unclear, indicating no report.