Table 2.

Oxford EBM [50] and SORT [40] evidence level score regarding the validity of the CKD273 classifier in CKD prediction

	Methodology	Samples collection at a common point	Sufficient follow-up time	Blind outcome criteria	Adjustment for prognostic factors	EBM score	SORT score
Argiles et al. [39]	Prospective cohort	No	Yes	Yes	No	Ib	1
Gu et al. [45]	Prospective cohort	No	Yes	Yes	Yes	−*	2
Roscioni et al. [38]	Prospective cohort	Yes	Yes	Yes	Yes	Ib	4
Schanstra et al. [41]	Prospective cohort	Yes	Yes	Yes	Yes	Ib	4

^*Not calculated (follow-up time insufficient). The table was adapted from Critselis and Lambers [36].