Correlation between Soluble α-Klotho and Renal Function in Patients with Chronic Kidney Disease: A Review and Meta-Analysis

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.