The role of systematic reviews in determining best practice in the management of end-stage renal disease
Four systematic literature reviews were undertaken to help define best clinical practice in the management of end-stage renal disease (ESRD). Only randomised controlled trials (RCTs) were included. The areas reviewed were (1) Synthetic versus cellulose/modified-cellulose membranes for haemodialysis in ESRD; (2) Bicarbonate versus acetate dialysate for haemodialysis in ESRD; (3) Short versus standard duration dialysis in haemodialysis in ESRD; and (4) Continuous Cyclic Peritoneal Dialysis (CCPD) versus Continuous Ambulatory Peritoneal Dialysis (CAPD) in ESRD. The paucity of trials made it difficult to determine best practice in relation to many outcome measures. The review identified only a modest benefit from synthetic membranes over cellulose membranes in reducing adverse symptoms during dialysis at considerable extra cost. There was good evidence to support the use of bicarbonate in preference to acetate haemodialysis on the basis of greater effectiveness and similar cost. The single study which considered haemodialysis duration did not produce data to support the equal safety of short duration dialysis compared with standard duration. Finally, though the single study identified tended to favour CCPD in preference to CAPD in terms of fewer peritonitis episodes the extra cost involved was considerable. Though approximately 16,000 abstracts were identified by the search strategy only forty-two RCTs met the inclusion criteria for any of the four reviews. Considering the volume of published work and the critical importance of the policy decisions being reviewed, it was disappointing to identify so few. These reviews have highlighted the need for further, large, multi-centre RCTs in nephrology and dialysis. Systematic literature reviews will play a key role in placing the practice of nephrology on a solid foundation of robust scientific evidence. They may also nurture a culture of clinical research in nephrology where the confusion and conflict of many small methodologically week trials is replaced by the scientific clarify of fewer, large, well conducted, methodologically sound RCTs.