Table 2.

Summary of quality indicators of non-randomised studies fulfilling inclusion criteria

Observational Study	Sabater [33]	Bagshaw [34]	Gettings [15]	Elahi [38]	Demirkilic [13]	Liu [21]	Andrade [36]	Wu [42]	Manche [40]	Iyem [39]	Shiao [41]	Carl [37]	Bagshaw [35]
Were criteria for initiation of RRT clearly defined in each group?	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Yes
Was the measurement of criterion (or lab value) for initiation of RRT reliable?	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	No	No	Yes	Yes	Yes
Was control group prospectively assembled? (vs historical, or case-control)	Yes	Yes	No	No	No	Yes	No	No	No	No	Yes	No	Yes
Were control and intervention group comparable with respect to disease type and demographics?	No	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Were the control and intervention group comparable with respect to disease severity?	No	No	Yes	Yes	Yes	No	Yes	Yes	No	Yes	Yes	Yes	Yes
Was dialysis type comparable between groups in terms of dose, solution used, filtration vs dialysis, and type of membrane?	No	No	Yes	Yes	No	No	No	No	No	Yes	Yes	No	No
Was there a description of withdrawals and dropouts?	No	Yes	No	Yes	No	No	No	No	No	No	No	No	Yes