Table 1.
Characteristics of 16 included studies.
| Authors | Location | Number (Qualified Rate %) |
Prevalence of FI, N Persons (%) |
Ref. No. |
|---|---|---|---|---|
| Yuan, 2021 [43] | Xi’an | 1152 (96.00%) | 583 (50.6%) | 213 |
| Hua, 2021 [44] | Nanjing | 305 (95.80%) | 133 (43.61%) | 186 |
| Fan, 2021 [45] | Zhengzhou | 508 (84.70%) | 189 (37.2%) | 177 |
| Yuan, 2020 [46] | Ningbo | 972 (97.20%) | 307 (31.60%) | 144 |
| Ji, 2019 [47] | Qingdao | 300 (93.75%) | 91 (30.30%) | 137 |
| Huang, 2019 [48] | Changchun | 268 (94.04%) | 133 (49.63%) | 134 |
| Zhao, 2019 [49] | Beijing | 1446 (95.40%) | 598 (41.22%) | 132 |
| Lin, 2019 [50] | Putian | 311 (94.24%) | 215 (69.13%) | 128 |
| Hui, 2019 [51] | Shanghai | 12,722 (99.76%) | 641 (5.00%) | 121 |
| Li, 2017 [52] | Chengdu | 523 (96.00%) | 170 (32.50%) | 109 |
| Liang, 2019 [53] | Shanghai | 904 (98.30%) | 187 (20.70%) | 95 |
| Qin, 2018 [54] | Nanchong | 213 (100.00%) | 56 (26.30%) | 87 |
| Jin, 2018 [55] | 12 cities of 6 provinces * |
2799 (100.00%) | 876 (31.3%) | 83 |
| Tao, 2021 [56] | Guilin | 1708 (94.89%) | 814 (47.66%) | 62 |
| Bai, 2018 [57] | Shanghai | 848 (80.76%) | 417 (49.17%) | 21 |
| Wang T, 2019 [20] | Hunan province |
703 (82.40%) | 228 (32.43%) | 4 |
* Twelve cities (Guangzhou, Jieyang, Chengdu, Luzhou, Wuhan, Jingzhou, Jinan, Jining, Hangzhou, Lishui, Shenyang, Chaoyang). Six provinces (Guangdong, Sichuan, Hubei, Shandong, Zhejiang, Liaoning).