2. Description of included studies according with the interventions used.

Categories of intervention	Study	Total number of studies	Total number of patients
HDF versus HD	Bammens 2004; Lin 2001; Locatelli 1994; Lornoy 1998; Teo 1987; Tuccillo 2002; Ward 2000; Wizemann 2000; Bolasco 2003; CONTRAST (Dutch) Study 2005; Cristofano 2004; Karamperis 2005; Mandolfo 2008; Pedrini 2011a; Righetti 2010; Schiffl 2007; Stefansson 2012; TURKISH HDF 2013; Vaslaki 2006ESHOL Study 2011; Kantartzi 2013; Ohtake 2012	22	3299
HF versus HD	Beerenhout 2005; Fox 1993; Schiffl 1992; Bolasco 2003; Santoro 2005a; PROFIL Study 2011	6	325
AFB versus HD	Basile 2001; Santoro 1999; Eiselt 2000; Noris 1998; Schrander vd Meer 1998; Selby 2006a; Todeschini 2002; Verzetti 1998	8	487
HDF versus AFB	Coll 2009; Ding 2002; Movilli 1996	3	59
HDF versus HF	Altieri 2004; Bolasco 2003; Meert 2009	3	199
More than two treatment arms	Bolasco 2003; Locatelli 1994; Schiffl 1992	3	383

AFB ‐ acetate‐free biofiltration; HDF ‐ haemodiafiltration; HD ‐ haemodialysis; HF ‐ haemofiltration