Table 2.
Characteristics of included studies.
| Study | Publish year | Nation | Average age | N | index | Correlation coefficient | Study design | Assay utilization | Intact/C-terminal of FGF-23 |
|---|---|---|---|---|---|---|---|---|---|
| Masashi Kitagawa | 2013 | Japan | 58 | 114 | GFR | 0.3913∗ | Cross-sectional | ELISA(Japan) | Intact |
| Age | -0.272∗ | ||||||||
| FGF23 | -0.1751∗ | ||||||||
| Ca | 0.1618∗ | ||||||||
| Phos | -0.3034∗ | ||||||||
|
| |||||||||
| Michishige Ozeki | 2014 | Japan | 68.9 | 185 | GFR | 0.209∗ | Retrospective | ELISA(Japan) | Intact |
| FGF23 | -0.14 | ||||||||
| Ca | 0.06∗ | ||||||||
| Phos | 0.05 | ||||||||
|
| |||||||||
| Tetsu Akimoto1 | 2012 | Japan | 56 | 131 | GFR | 0.232 | Cross-sectional | ELISA(Japan) | Nr |
| Age | -0.172 | ||||||||
|
| |||||||||
| Hyoung Rae Kim | 2013 | Korea | 45.7 | 243 | GFR | 0.502 | Cross-sectional | ELISA(Japan) | Intact |
| Age | -0.395 | ||||||||
| FGF23 | -0.245 | ||||||||
| Ca | 0.257 | ||||||||
| Phos | -0.169 | ||||||||
|
| |||||||||
| Valerie Hage | 2014 | France | 46.7 | 60 | GFR | 0.11 | Cross-sectional | ELISA(Japan) | Nr |
| FGF23 | 0.23 | ||||||||
|
| |||||||||
| Sarah Seiler | 2012 | Germany | 65.5 | 321 | FGF23 | -0.03∗ | Prospective | ELISA(Japan) | C-terminal |
| Ca | 0.01∗ | ||||||||
| Phos | -0.06∗ | ||||||||
|
| |||||||||
| Ivana Pavik | 2013 | Switzerland | 52.7 | 87 | GFR | 0.64 | Cross-sectional | ELISA(Japan) | C-terminal |
|
| |||||||||
| Yoshiko Shimamura | 2012 | Japan | 63.8 | 292 | GFR | 0.441 | Prospective | ELISA(Japan) | Intact |
| Age | -0.345 | ||||||||
| FGF23 | -0.156 | ||||||||
|
| |||||||||
| Alexandra Scholze | 2014 | Denmark | 68 | 24 | GFR | 0.11∗ | RCT | ELISA(Japan) | Intact |
| Age | -0.25∗ | ||||||||
| FGF23 | 0.09∗ | ||||||||
| Phos | -0.10∗ | ||||||||
Note. ∗spearman correlation coefficient, otherwise, Pearson correlation coefficient. Nr representative not reported.