Systematic review and economic modelling of the effectiveness and cost-effectiveness of non-surgical treatments for women with stress urinary incontinence

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of non-surgical treatments for women with stress urinary incontinence (SUI) through systematic review and economic modelling.

DATA SOURCES

The Cochrane Incontinence Group Specialised Register, electronic databases and the websites of relevant professional organisations and manufacturers, and the following databases: CINAHL, EMBASE, BIOSIS, Science Citation Index and Social Science Citation Index, Current Controlled Trials, ClinicalTrials.gov and the UKCRN Portfolio Database.

STUDY SELECTION

The study comprised three distinct elements. (1) A survey of 188 women with SUI to identify outcomes of importance to them (activities of daily living; sex, hygiene and lifestyle issues; emotional health; and the availability of services). (2) A systematic review and meta-analysis of non-surgical treatments for SUI to find out which are most effective by comparing results of trials (direct pairwise comparisons) and by modelling results (mixed-treatment comparisons - MTCs). A total of 88 randomised controlled trials (RCTs) and quasi-RCTs reporting data from 9721 women were identified, considering five generic interventions [pelvic floor muscle training (PFMT), electrical stimulation (ES), vaginal cones (VCs), bladder training (BT) and serotonin-noradrenaline reuptake inhibitor (SNRI) medications], in many variations and combinations. Data were available for 37 interventions and 68 treatment comparisons by direct pairwise assessment. Mixed-treatment comparison models compared 14 interventions, using data from 55 trials (6608 women). (3) Economic modelling, using a Markov model, to find out which combinations of treatments (treatment pathways) are most cost-effective for SUI.

DATA EXTRACTION

Titles and abstracts identified were assessed by one reviewer and full-text copies of all potentially relevant reports independently assessed by two reviewers. Any disagreements were resolved by consensus or arbitration by a third person.

RESULTS

Direct pairwise comparison and MTC analysis showed that the treatments were more effective than no treatment. Delivering PFMT in a more intense fashion, either through extra sessions or with biofeedback (BF), appeared to be the most effective treatment [PFMT extra sessions vs no treatment (NT) odds ratio (OR) 10.7, 95% credible interval (CrI) 5.03 to 26.2; PFMT + BF vs NT OR 12.3, 95% CrI 5.35 to 32.7]. Only when success was measured in terms of improvement was there evidence that basic PFMT was better than no treatment (PFMT basic vs NT OR 4.47, 95% CrI 2.03 to 11.9). Analysis of cost-effectiveness showed that for cure rates, the strategy using lifestyle changes and PFMT with extra sessions followed by tension-free vaginal tape (TVT) (lifestyle advice-PFMT extra sessions-TVT) had a probability of greater than 70% of being considered cost-effective for all threshold values for willingness to pay for a QALY up to 50,000 pounds. For improvement rates, lifestyle advice-PFMT extra sessions-TVT had a probability of greater than 50% of being considered cost-effective when society's willingness to pay for an additional QALY was more than 10,000 pounds. The results were most sensitive to changes in the long-term performance of PFMT and also in the relative effectiveness of basic PFMT and PFMT with extra sessions.

LIMITATIONS

Although a large number of studies were identified, few data were available for most comparisons and long-term data were sparse. Challenges for evidence synthesis were the lack of consensus on the most appropriate method for assessing incontinence and intervention protocols that were complex and varied considerably across studies.

CONCLUSIONS

More intensive forms of PFMT appear worthwhile, but further research is required to define an optimal form of more intensive therapy that is feasible and efficient for the NHS to provide, along with further definitive evidence from large, well-designed studies.

Periurethral injection therapy for urinary incontinence in women

BACKGROUND

Periurethral or transurethral injection of bulking agents is a surgical procedure most often used for the treatment of stress urinary incontinence a common, troublesome symptom amongst adult women.

OBJECTIVES

To assess the effects of periurethral/transurethral injection therapy in the treatment of urinary incontinence in women.

SEARCH STRATEGY

We searched the Cochrane Incontinence Group Specialised Trials Register (28 February 2007), MEDLINE (January 1996 to March 2007, PREMEDLINE (7 February 2007) and the reference lists of relevant articles.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials of treatment for urinary incontinence, in which at least one management arm involved periurethral/transurethral injection therapy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed methodological quality of each study using explicit criteria. Data extraction was undertaken independently using a standard form and clarification concerning possible unreported data sought directly from the investigators.

MAIN RESULTS

We identified twelve trials including 1318 women that met the inclusion criteria. The limited data available were not suitable for meta-analysis. Injection of autologous fat was compared to placebo in a study of 68 women which was terminated early because of safety concerns. No differences in subjective or objective outcome were found in the two groups. No studies were found comparing injection therapy with conservative treatment. Two studies that compared injection with surgical management found significantly better objective outcome in the surgical group. Eight studies compared different agents - all results had wide confidence intervals. Silicone particles, calcium hydroxylapatite, ethylene vinyl alcohol and carbon spheres gave improvements equivalent to collagen. Porcine dermal implant gave improvements comparable to silicone at six months. A comparison of periurethral and transurethral methods of delivery of the bulking agent found similar outcome but a higher rate of early complications in the periurethral group.

AUTHORS' CONCLUSIONS

Despite five additional trials, this updated review is still an unsatisfactory basis for practice. The trials were small and generally of moderate quality. The only evidence of benefit comes for within-group short-term changes following injection. The finding that placebo saline injection was followed by a similar symptomatic improvement questions the mechanism of any effects. There were no trials in comparison with pelvic floor muscle training -the obvious non-surgical comparator. Greater symptomatic improvement was observed after surgery, although these advantages need to be set against likely higher risks. No clear-cut conclusions could be drawn from trials comparing alternative agents; one small trial suggests that periurethral injection may carry more risks than transurethral injection. The single trial of autologous fat provides a reminder that periurethral injections can occasionally cause serious side-effects. Pending further evidence, injection therapy may represent a useful option for short-term symptomatic relief amongst selected women with co-morbidity that precludes anaesthesia - two or three injections are likely to be required to achieve a satisfactory result.

Continuous ambulatory peritoneal dialysis versus automated peritoneal dialysis for end-stage renal disease

BACKGROUND

Peritoneal dialysis (PD) can be performed either manually as in continuous ambulatory peritoneal dialysis (CAPD) or using mechanical devices as in automated PD (APD). APD has been considered to have several advantages over CAPD such as reduced incidence of peritonitis, mechanical complications and greater psychosocial acceptability.

OBJECTIVES

To assess the comparative efficacy of CAPD and APD in patients who are dialysed for end-stage renal disease (ESRD).

SEARCH STRATEGY

We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Renal Group's specialised register and CINAHL. Authors of included studies were contacted, reference lists of identified RCTs and relevant narrative reviews were screened. Date of most recent search: May 2006

SELECTION CRITERIA

RCTs comparing CAPD with APD in patients with ESRD.

DATA COLLECTION AND ANALYSIS

Data were abstracted independently by two authors onto a standard form. Relative risk (RR) for dichotomous data and a mean difference (MD) for continuous data were calculated with 95% confidence intervals (CI).

MAIN RESULTS

Three trials (139 patients) were included. APD did not differ from CAPD with respect to mortality (RR 1.49, 95% CI 0.51 to 4.37), risk of peritonitis (RR 0.75, 95% CI 0.50 to 1.11), switching from original PD modality to a different dialysis modality (RR 0.50, 95% CI 0.25 to 1.02), hernias (RR 1.26, 95% interval 0.32 to 5.01), PD fluid leaks (RR 1.06, 95% CI 0.11 to 9.83), PD catheter removal (RR 0.64, 95% CI 0.27 to 1.48) or hospital admissions (RR 0.96, 95% CI 0.43 to 2.17). There was no difference between either PD modality with respect to residual renal function (MD -0.17, 95% CI -1.66 to 1.32). One study found that peritonitis rates and hospitalisation were significantly less in patients on APD when results were expressed as episodes/patient-year. Another study found that patients on APD had significantly more time for work, family and social activities.

AUTHORS' CONCLUSIONS

APD has not been shown to have significant advantages over CAPD in terms of important clinical outcomes. APD may however be considered advantageous in select group of patients such as in the younger PD population and those in employment or education due to its psychosocial advantages. There is a need for a RCT comparing CAPD with APD with sufficiently large patient numbers looking at important clinical outcomes including residual renal function, accompanied by an economic evaluation to clarify the relative clinical and cost-effectiveness of both modalities.

Frequency of administration of recombinant human erythropoietin for anaemia of end-stage renal disease in dialysis patients

BACKGROUND

The benefits of recombinant human erythropoietin (rHuEPO) administration in dialysis patients have been demonstrated, however the optimal frequency regimen have yet to be established.

OBJECTIVES

To assess the effects of different frequency regimens of rHuEPO administration in dialysis patients on anaemia correction, quality of life and optimal use.

SEARCH STRATEGY

We searched 13 electronic databases (1980 to May 2001) the internet (August 1997), handsearched Kidney International (1983 to May 1997), contacted known investigators, biomedical companies, and screened reference lists of relevant articles. Most recent search: The Cochrane Renal Group's specialised register (June 2004) and The Cochrane Library (Issue 3, 2004).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing different frequencies of rHuEPO administration in dialysis patients. We compared haemodialysis and CAPD patients and subcutaneous and intravenous administration.

DATA COLLECTION AND ANALYSIS

Quality assessment was performed by two assessors. Data were abstracted by a single author onto a standard form, and a sample was checked by another author. Results were expressed as relative risk (RR) or weighted mean difference (WMD) with 95% confidence intervals (CI).

MAIN RESULTS

Eleven studies (719 patients) were included. There was no significant difference in maintaining target haemoglobin for once versus twice weekly administration (one study, 20 patients: RR 1.00, 95% CI 0.42 to 2.40) or mean haemoglobin after 12 weeks of therapy between haemodialysis and CAPD patients (two studies: WMD -0.21 g/dL, 95% CI -0.98 to 0.56) At the end of study for once versus thrice weekly administration (three studies: SMD -0.31, 95% CI -0.67 to 0.06) and at the end of maintenance phase (one study: WMD -0.2 g/dL, 95% CI -0.65 to 0.25) there was no significant difference. More rHuEPO was required by haemodialysis patients receiving once weekly versus twice weekly doses (WMD 12.0 U/kg, 95% CI 0.24 to 23.76). No difference was found for CAPD patients alone or combined (WMD 4.38 U/kg, 95% CI -11.28 to 20.04). Once versus thrice weekly administration was not significant (WMD 10.00 U/kg, 95% CI -80.87 to 100.87). There was no difference in the frequency of adverse events.

AUTHORS' CONCLUSIONS

There is no significant difference between once weekly versus thrice weekly subcutaneous administration of rHuEPO. Once weekly administration would require an additional 12 U/kg/wk for patients on haemodialysis, however this is based on one very small study. Cost of additional rHuEPO needs to assessed with regard to patient preference and compliance.

Recombinant human erythropoietin for chronic renal failure anaemia in pre-dialysis patients

BACKGROUND

Treatment with recombinant human erythropoietin (rHu EPO) in dialysis patients has been shown to be highly effective in terms of correcting anaemia and improving quality of life. There is debate concerning the benefits of rHu EPO use in pre-dialysis patients which may accelerate the deterioration of renal function. However the opposing view is that if rHu EPO is as effective in pre-dialysis patient's, improving the patients sense of well-being may result in the onset of dialysis being delayed.

OBJECTIVES

To assess the effects of rHu EPO use in pre-dialysis patients with renal anaemia.

SEARCH STRATEGY

The initial search included 13 electronic databases (1980 to May 2001) an internet search (August 1997), handsearching of Kidney International (1983 to May 1997), contact with known investigators and biomedical companies, and reference list of relevant articles. For this update we searched the Cochrane Renal Group's specialised register (June 2004) and The Cochrane Library (Issue 3, 2004).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing the use of rHu EPO with no treatment or placebo in pre-dialysis patients.

DATA COLLECTION AND ANALYSIS

Only published data were used. Quality assessment was performed by two assessors independently. Data were abstracted by a single author onto a standard form, a sample of which was checked by another author. Results were expressed as relative risk (RR) or weighted mean difference (WMD) with 95% confidence intervals (CI).

MAIN RESULTS

Fifteen trials (461 participants) were included. There was a marked improvement in haemoglobin (WMD 1.82 g/dL, 95% CI 1.35 to 2.28) and haematocrit (WMD 9.85%, 95% CI 8.35 to 11.34) with treatment and a decrease in the number of patients requiring blood transfusions (RR 0.32, 95% CI 0.12 to 0.83). The data from studies reporting quality of life or exercise capacity demonstrated an improvement in the treatment group. Most of the measures of progression of renal disease showed no statistically significant difference. No significant increase in adverse events was identified.

AUTHORS' CONCLUSIONS

Treatment with rHu EPO in pre-dialysis patients corrects anaemia, avoids the requirement for blood transfusions and also improves quality of life and exercise capacity. We were unable to assess the effects of rHu EPO on progression of renal disease, delay in the onset of dialysis or adverse events. Based on the current evidence, decisions on the putative benefits in terms of quality of life are worth the extra costs of pre-dialysis rHu EPO need careful evaluation.

Continuous ambulatory peritoneal dialysis (CAPD) versus hospital or home haemodialysis for end-stage renal disease in adults

BACKGROUND

Renal replacement therapy (RRT) with dialysis and transplantation is the only means of sustaining life for patients with end-stage renal disease (ESRD). Although transplantation is the treatment of choice, the number of donor kidneys are limited and transplants may fail. Hence many patients require long-term or even life-long dialysis. Continuous ambulatory peritoneal dialysis (CAPD) is an alternative to hospital or home haemodialysis for patients with ESRD.

OBJECTIVES

To assess the benefits and harms of CAPD versus hospital or home haemodialysis for adults with ESRD.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL in The Cochrane Library), the Cochrane Renal Group's specialised register, MEDLINE (1966 - May 2002), EMBASE (1980 - May 2002), BIOSIS, CINAHL, SIGLE and NRR without language restriction. Reference lists of retrieved articles and conference proceedings were searched and known investigators and biomedical companies were contacted. Date of most recent search January 2004.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing CAPD to hospital or home haemodialysis for adults with ESRD were to be included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assess the methodological quality of studies. Data was abstracted from included studies onto a standard form by one reviewer and checked by another. Statistical analyses were performed using the random effects model and the results expressed as relative risk (RR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes with 95% confidence intervals (CI).

MAIN RESULTS

One trial, reported in abstract form only, was located in the most recent search. There was no statistical difference in death or quality adjusted life years score at 2 years between peritoneal dialysis or haemodialysis patients.

REVIEWERS' CONCLUSIONS

There is Insufficient data to allow conclusions to be drawn about the relative effectiveness of CAPD compared with hospital or home haemodialysis for adults with ESRD. Efforts should be made to start and complete adequately powered RCTs, which compare the different dialysis modalities.

Systematic review of the clinical effectiveness and cost-effectiveness of tension-free vaginal tape for treatment of urinary stress incontinence

OBJECTIVES

To evaluate the effectiveness and cost-effectiveness of tension-free vaginal tape (TVT) in comparison with the standard surgical interventions currently used.

DATA SOURCES

Literature searches were carried out on electronic databases and websites for data covering the period 1966--2002. Other sources included references lists of relevant articles; selected experts in the field; abstracts of a limited number of conference proceedings titles; and the Internet.

REVIEW METHODS

A systematic review of studies including comparisons of TVT with any of the comparators was conducted. Alternative treatments considered were abdominal retropubic colposuspension (including both open and laparoscopic colposuspension), traditional suburethral sling procedures and injectable agents (periurethral bulking agents). The identified studies were critically appraised and their results summarised. A Markov model comparing TVT with the comparators was developed using the results of the review of effectiveness and data on resource use and costs from previously conducted studies. The Markov model was used to estimate costs and quality-adjusted life-years for up to 10 years following surgery and it incorporated a probabilistic analysis and also sensitivity analysis around key assumptions of the model.

RESULTS

Based on limited data from direct comparisons with TVT and from systematic reviews, laparoscopic colposuspension and traditional slings have broadly similar cure rates to TVT and open colposuspension, whereas injectable agents appear to have lower cure rates. TVT is less invasive than colposuspension and traditional sling procedures, and is also usually performed under regional or local anaesthesia. The principal operative complication is bladder perforation. There are currently no randomised controlled trial (RCT) data beyond 2 years post-surgery, and long-term effects are therefore currently not known reliably. TVT was more likely to be considered cost-effective compared with the other surgical procedures. Increasing the absolute probability of cure following TVT reduced the likelihood that TVT would be considered cost-effective.

CONCLUSIONS

The long-term performance of TVT in terms of both continence and unanticipated adverse effects is not known reliably at the moment. Despite relatively few robust comparative data, it appears that in the short to medium term TVT's effectiveness approaches that of alternative procedures currently available, and is of lower cost. As TVT is a less invasive procedure, it is possible that some women who would currently be managed non-surgically will be considered eligible for TVT. Increased adoption of TVT will require additional surgeons proficient in the technique. It is likely that some of the higher rates of complications, e.g. bladder perforation, reported for TVT are associated with a 'learning curve'. Appropriate training will therefore be needed for surgeons new to the operation, in respect of both the technical aspects of the procedure and the choice of women suitable for the operation. Further research suggestions include unbiased assessments of longer term performance from follow-up of controlled trials or population-based registries; more data from methodologically sound RCTs using standard outcome measures; a surveillance system to detect longer term complications, if any, associated with the use of tape; and rigorous evaluation before extending the use of TVT to women who are currently managed non-surgically.

Continuous ambulatory peritoneal dialysis (CAPD) versus hospital or home haemodialysis for end-stage renal disease in adults

BACKGROUND

Renal replacement therapy (RRT) with dialysis and transplantation is the only means of sustaining life for patients with end-stage renal disease (ESRD). Although transplantation is the treatment of choice, the number of donor kidneys are limited and transplants may fail. Hence many patients require long-term or even life-long dialysis. Continuous ambulatory peritoneal dialysis (CAPD) is an alternative to hospital or home haemodialysis for patients with ESRD.

OBJECTIVES

To assess the benefits and harms of CAPD versus hospital or home haemodialysis for adults with ESRD.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register (Cochrane Library, Issue 2, 2002), the Cochrane Renal Group's Specialised Register (May 2002), MEDLINE (1966 - May 2002), EMBASE (1980 - May 2002), BIOSIS, CINHAL, SIGLE and NRR without language restriction. Reference lists of retrieved articles and conference proceedings were searched and known investigators and biomedical companies were contacted.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing CAPD to hospital or home haemodialysis for adults with ESRD were to be included.

DATA COLLECTION AND ANALYSIS

Two reviewers were to independently assess the methodological quality of studies. Data was to be abstracted from included studies onto a standard form by one reviewer and checked by another. Statistical analyses were to be performed using the random effects model and the results to be expressed as relative risk (RR) with 95% confidence intervals (95% CI).

MAIN RESULTS

Despite extensive searching, no RCTs or quasi-RCTs were identified.

REVIEWER'S CONCLUSIONS

Data are not available to allow conclusions to be drawn about the relative effectiveness of CAPD compared with hospital or home haemodialysis for adults with ESRD. Efforts should be made to start and complete adequately powered RCTs, which compare the different dialysis modalities.

Frequency of administration of recombinant human erythropoietin for anaemia of end-stage renal disease in dialysis patients

BACKGROUND

Although the benefits of recombinant human erythropoietin (rHu EPO) administration in dialysis patients have been demonstrated the optimal frequency regimen has not as yet been established. Treatment with rHu EPO is expensive, there is therefore a need for optimising the efficiency of its administration.

OBJECTIVES

The objectives of this review were to assess the effects of different frequency regimens of rHu EPO administration in dialysis patients in terms of i) effectiveness (correction of anaemia, quality of life and freedom from adverse events) ii) efficiency (optimal resource use) of different rHu EPO dose regimen policies.

SEARCH STRATEGY

We searched MEDLINE (1980 to May Week 3 2001), EMBASE (1984 to Week 24 2001), BIOSIS (1985 to January 1997), CINAHL (1982 to October 1997), The Cochrane Library (Issue 1, 1997), CHEMABS (1984 to November 1996), SIGLE (1980 to June 1996), CRIB (10th edition, 1995), UK NRR (14th consolidation, September 1996), RSC ( 1980 to February 1997), HealthSTAR (1995 to October 1997), IBSS (1984 to July 1997), NEED (July 1997) and reference lists of relevant articles. We contacted biomedical companies and investigators in the field and we hand searched Kidney International (including all supplements but excluding all conference proceedings except for 1994) July 1983 to May 1997 inclusive. The Internet was also searched on: August 1997. We had also identified some studies from a previous broad search for all randomised controlled trials (RCTs) relevant to the management of end-stage renal disease. Date of the most recent search: June 2001.

SELECTION CRITERIA

All randomised or quasi randomised controlled trials comparing different frequencies of rHu EPO administration in dialysis patients. Subgroup analyses were performed comparing haemodialysis and CAPD patients and also subcutaneous and intravenous administration.

DATA COLLECTION AND ANALYSIS

Only published data were used. Data were abstracted by a single investigator on to a standard form. The data abstracted were relevant to the predetermined outcome measures: measures of correction of anaemia, rHu EPO dose, quality of life measures, adverse events, number of withdrawals from study, mortality. Where appropriate, a summary relative risk (RR) was calculated for dichotomous data and a weighted mean difference (WMD) or standardised mean difference (SMD) for continuous data.

MAIN RESULTS

Eight studies met our inclusion criteria. When once a week administration was compared with twice weekly there was no significant difference in the ability to maintain the target haemoglobin (RR 1.00, 95% CI 0.42 to 2.40). Mean haemoglobin after twelve weeks of therapy was not different between the two groups (WMD -0.21g/dl, 95% CI -0.98 to 0.56). No difference was found in mean haemoglobin or haematocrit at the end of any studies which compared once with thrice weekly administration of rHu EPO (SMD -0.31, 95% CI -0.67 to 0.06). A single study which compared once with more that thrice weekly administration showed no significant difference in mean haemoglobin at the end of the maintenance phase (mean difference -0.2g/dl, 95% CI -0.65 to 0.25). The dosage of erythropoietin required by those on haemodialysis receiving rHu EPO once weekly was just significantly more (WMD 12.0 U/kg, 95% CI 0.24 to 23.76) than those receiving it twice weekly but the confidence interval is wide. No such difference was found for CAPD patients nor when the results were combined (WMD 5.15 U/kg, 95% CI -3.74 to 14.05). The result was not significant when comparing once weekly with thrice weekly administration (WMD 10.00 U/kg, 95% CI -80.87 to 100.87). There was no difference in the frequency of adverse events between any of the groups studies.

REVIEWER'S CONCLUSIONS

There is no significant difference between once weekly versus thrice weekly subcutaneous administration of rHu EPO. Once weekly administration of rHu EPO would require an additional 12U/kg/week for patients on haemodialysis, however this is based on one very small study. The cost of this additional hRu EPO nee, however this is based on one very small study. The cost of this additional hRu EPO needs to assessed, in particular with regard to patient preference and compliance.

Comparison of cellulose, modified cellulose and synthetic membranes in the haemodialysis of patients with end-stage renal disease

BACKGROUND

When the kidney fails the blood borne metabolites of protein breakdown and water cannot be excreted. The principle of haemodialysis is that such substances can be removed when blood is passed over a semipermeable membrane. Natural membrane materials can be used including cellulose or modified cellulose, more recently various synthetic membranes have been developed. Synthetic membranes are regarded as being more "biocompatible" in that they incite less of an immune response than cellulose-based membranes.

OBJECTIVES

To assess the effects of different haemodialysis membrane material in patients with end-stage renal disease (ESRD).

SEARCH STRATEGY

We searched Medline (1966 to December 2000), Embase (1981 to November 2000), PreMedline (29 November 2000), HealthStar (1975 to December 2000), Cinahl (1982 to October 2000), The Cochrane Controlled Trials Register (Issue 1, 1996), Biosis (1989 to June 1995), Sigle (1980 to June 1996), Crib (10th edition, 1995), UK National Research Register (September 1996), and reference lists of relevant articles. We contacted biomedical companies, investigators and we hand searched Kidney International (1980 to 1997). Date of the most recent searches: November 2000.

SELECTION CRITERIA

All randomised or quasi-randomised clinical trials comparing different haemodialysis membrane material in patients with ESRD.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the methodological quality of studies. Data was abstracted from included studies onto a standard form by one reviewer and checked by another.

MAIN RESULTS

Twenty seven studies met our inclusion criteria and where possible data from these were summated by meta-analyses (Peto's odds ratio (OR) and weighted mean difference (WMD) with 95% confidence intervals (CI)). Twenty two outcome measures were sought in 10 broad areas. For two (number of episodes of significant infection per year and quality of life) no data were available. For the comparison of cellulose with synthetic membranes, data for 12/20 outcome measures were available in only a single trial. For modified cellulose and synthetic membranes, data for three outcome measures were available in one trial only and for 12 of the outcomes no data were found, crossover studies were analysed separately and studies which randomised by patient yet analysed by dialysis sessions adjusted for clustering. Pre-dialysis beta2 microglobulin concentrations were significantly lower at the end of the studies in patients treated with synthetic membranes (WMD - 14.5; 95% CI -17.4 to -11.6). One crossover study showed a lowering of beta2 microglobulin when low flux synthetic membranes were used. When analysed for a change in beta2 microglobulin across a trial a fall was only noted when high flux membranes were used. In one very small study the incidence of amyloid was less in patients who were dialysed for six years with high flux synthetic membranes (OR 0.05; 95% CI 0.01 to 0.18). In the single study which measured triglyceride values there was a significant difference in favour of the synthetic (high flux) membrane (WMD -0.66; 95% CI -1.18 to -0.14). Serum albumin was higher in patients treated with synthetic membranes (both low and high flux) although this just bordered statistical significance (WMD -0.09; 95% CI -0.18 to 0.00). Dialysis adequacy measured by Kt/V was marginally higher when cellulose membranes were used (WMD 0.10; 95% CI 0.04 to 0.16). There was no significant difference between these membranes for any of the other clinical outcomes measures but confidence intervals were generally wide. No differences were found between modified cellulose and synthetic membranes although many fewer trials were carried out for this comparison.

REVIEWER'S CONCLUSIONS

For clinical practice This systematic literature review has generated no evidence of benefit when synthetic membranes were used compared with cellulose/modified cellulose membranes in terms of reduced mortality nor reduction in dialysis related adverse symptoms. Despite the relatively large number of RCTs undertaken in this area none of the included studies reported any measures of quality of life. End-of-study beta2 microglobulin values, and possibly the development of amyloid disease, were less in patients treated with synthetic membranes compared with cellulose membranes. Plasma triglyceride values were also lower with synthetic membranes in the single study that measured this outcome. Differences in these outcomes may have reflected the high flux of the synthetic membrane. Serum albumin was higher when synthetic membranes of both high and low flux were used. Kt/V and urea reduction ratio were higher when cellulose or modified cellulose membranes were used in the few studies that measured these outcomes. We are hesitant to recommend the universal use of synthetic membranes for haemodialysis in patients with ESRD because of; the small number of trials (particularly for modified cellulose membranes, most with low patient numbers), the heterogeneity of many of the trials compared, the variations in membrane flux, the differences in exclusion criteria, particularly relating to comorbidity and the relative lack of patient-centred outcomes studied. Such evidence as we have favours synthetic membranes but even if we assume extra benefit it may be at considerable cost, particularly if high flux synthetic membranes were to be used. For further research A further systematic review of RCTs comparing high and low flux haemodialysis membranes, subgrouped according to membrane composition (cellulose, modified cellulose, synthetic) and reporting clinical outcomes of major importance to patients needs to be undertaken. Further pragmatic RCTs are required to compare the different dialysis membranes available. We recommend that they: - Take into account other properties including flux as well as the material from which the membrane is made and test modified cellulose membranes as well as standard ones. - Record an agreed minimum dataset on primary outcomes of major importance to patients. - Explicitly record whether symptoms are patient- or staff-reported recognising that generally patient reporting will be more appropriate for evaluating effectiveness but staff reported data may be necessary for calculating the cost of treating complications. - Be multi-centre (and possibly multinational) to have sufficient patients to complete the study to allow for a considerable number of withdrawals and dropouts. - Have sufficient length of follow up to draw conclusions for important clinical outcome measures and continue to follow patients who have renal transplants. - Include older patients and those with comorbid illnesses and take into account age and comorbidity when assessing outcomes (possibly by stratification at trial entry). - Carry out, in parallel, an economic evaluation of the different policies being compared in the trial.

Double bag or Y-set versus standard transfer systems for continuous ambulatory peritoneal dialysis in end-stage renal disease

BACKGROUND

Peritonitis is the most frequent serious complication of continuous ambulatory peritoneal dialysis (CAPD). It has a major influence on the number of patients switching from CAPD to haemodialysis and has probably restricted the wider acceptance and uptake of CAPD as an alternative mode of dialysis.

OBJECTIVES

This systematic review sought to determine if modifications of the transfer set (Y-set or double bag systems) used in CAPD exchanges are associated with a reduction in peritonitis and an improvement in other relevant outcomes.

SEARCH STRATEGY

A broad search strategy was employed which attempted to identify all RCTs or quasi-RCTs relevant to the management of end-stage renal disease (ESRD). Five electronic databases were searched (Medline 1966-1999, EMBASE 1984-1999, CINAHL 1982-1996, BIOSIS 1985-1996 and the Cochrane Library), authors of included studies and relevant biomedical companies were contacted, reference lists of identified RCTs and relevant narrative reviews were screened and Kidney International 1980-1997 was hand searched.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing double bag, Y-set and standard CAPD exchange systems in patients with ESRD.

DATA COLLECTION AND ANALYSIS

Data were abstracted by a single investigator onto a standard form and subsequently entered into Review Manager 4.0.4. Odds Ratio (OR) for dichotomous data and a (Weighted) Mean Difference (WMD) for continuous data were calculated with 95% confidence intervals (95% CI).

MAIN RESULTS

Twelve eligible trials with a total of 991 randomised patients were identified. In trials comparing either the Y-set or double bag systems with the standard systems significantly fewer patients (OR 0.33, 95% CI 0.24 to 0.46) experienced peritonitis and the number of patient-months on CAPD per episode of peritonitis were consistently greater. When the double bag systems were compared with the Y-set systems significantly fewer patients experienced peritonitis (OR 0.44, 95% CI 0.27 to 0.71) and the numbers of patient-months on CAPD/ episode of peritonitis were also greater.

REVIEWER'S CONCLUSIONS

Double bag systems should be the preferred exchange systems in CAPD.

Recombinant human erythropoietin for chronic renal failure anaemia in pre-dialysis patients

BACKGROUND

Treatment with recombinant human erythropoietin (rHu EPO) in dialysis patients has been shown to be highly effective in terms of correcting anaemia and improving quality of life. There is debate concerning the benefits of rHu EPO use in pre-dialysis patients. There is a concern that rHu EPO may accelerate the deterioration in renal function, however the opposing view is that if rHu EPO is as effective in pre-dialysis patients that by improving the patients sense of well-being the onset of dialysis could be delayed.

OBJECTIVES

To assess the effects of rHu EPO use in pre-dialysis patients with renal anaemia.

SEARCH STRATEGY

We searched MEDLINE (1980 to May Week 3 2001), EMBASE (1984 to Week 24 2001), BIOSIS (1985 to January 1997), CINAHL (1982 to October 1997), The Cochrane Library (Issue 1, 1997), CHEMABS (1984 to November 1996), SIGLE (1980 to June 1996), CRIB (10th edition, 1995), UK NRR (14TH consolidation, September 1996), RSC ( 1980 to February 1997), HealthSTAR (1995 to October 1997), IBSS (1984 to July 1997), NEED (July 1997) and reference lists of relevant articles. We contacted biomedical companies and investigators in the field and we hand searched Kidney International (including all supplements but excluding all conference proceedings except for 1994) July 1983 to May 1997 inclusive. The internet was also searched on: August 1997. We had also identified some studies from a previous broad search for all randomised controlled trials (RCTs) relevant to the management of end-stage renal disease. Date of the most recent search: June 2001.

SELECTION CRITERIA

RCTs or quasi-RCTs comparing the use of rHu EPO with no rHu EPO or placebo in pre-dialysis patients.

DATA COLLECTION AND ANALYSIS

Only published data were used. Data were abstracted by a single investigator onto a standard form. A sample of the data abstracted was double-checked by another reviewer. The data abstracted were relevant to the predetermined outcome measures. Some authors were contacted to clarify how patients were allocated to groups. All authors from included studies were contacted for missing information.

MAIN RESULTS

Twelve studies with a total of 232 participants met the inclusion criteria and where possible data from these were summated by meta-analyses (Peto's Odds Ratio (OR) and Weighted Mean Difference (WMD)). The majority of the trials included small numbers and were of short duration (8-10 weeks) with the exception of three trials. There was a marked improvement in haemoglobin (mean difference 2.3g/dL, 95% CI 1.37 to 3.23) and haematocrit (WMD 9.92%, 95% CI 8.78 to 11.05) with the treatment and a decrease in the number of patients requiring blood transfusion (OR 0.25, 95% CI 0.09 to 0.69). The data from all studies which reported quality of life or exercise capacity demonstrated an improvement in the rHu EPO group. None of the measures of progression of renal disease (when a summary statistic was calculated) demonstrated a statistically significant difference. Though the requirement for antihypertensive treatment appears to be increased by rHu EPO (OR 1.84, 95% CI 1.02 to 3.32), there was no other statistically significant increase in adverse events. Based on the limited current evidence, decisions therefore have to be made on whether the putative benefits in terms of quality of life identified in the review are worth the extra costs of pre-dialysis rHu EPO.

REVIEWER'S CONCLUSIONS

This review has shown that treatment with rHu EPO in pre-dialysis patients corrects anaemia and avoids the requirement for blood transfusions. There are also improvements in quality of life and exercise capacity. There may be increased hypertension. Most of the trials were not of sufficient duration to assess the effects of rHu EPO on progression of renal disease. In the long term, questions still remain about whether pre-dialysis rHu EPO either speeds up or delays the onset of dialysis. Thus there is insufficient evidence on the total costs and benefits of treating pre-dialysis patients with rHu EPO.

Evaluation of clinical guidelines for the management of end-stage renal disease in europe: the EU BIOMED 1 study

BACKGROUND

There are wide national and international variations in the management of patients with end-stage renal disease (ESRD). The aim of this study was to develop, harmonize, implement, and evaluate consensus-based clinical guidelines for the management of renal anaemia and renal bone disease in patients with ESRD, and for the prevention and management of cytomegalovirus disease in renal transplant recipients across six renal centres in Europe.

METHODS

The trial was a prospective, multicentre, randomized balanced incomplete block design. Nephrologists from the six European renal units were randomized to develop and implement guidelines for two out of the three conditions and to act as a control for the third condition. Data were collected pre- (1 year) and post- (9 months) intervention on aspects of patient monitoring, management, and outcome.

RESULTS

Eight hundred and twenty-nine dialysis patients from the six European dialysis centres were included in the study. Multivariate analysis (adjusting for case-mix and secular trends) showed a significant increase in the number of monitoring events in the guideline group compared with control group (6%, 95% CI, 1-11%). There was no concomitant increase in either appropriate management or the number of favourable patient outcomes.

CONCLUSIONS

In the first European collaboration on renal guidelines, the introduction of the guidelines improved the monitoring of the patients, but did not improve patient management or outcome. This study suggests the potential for creating clinical guidelines with the aim of standardizing treatment protocols across international boundaries, and improving the quality of the medical care provided.

Evidence-based medicine and health economics: a case study of end stage renal disease

This paper explores the potential for use of an economic evaluation framework alongside systematic reviews. Clinical issues in dialysis therapy for end stage renal disease are used as case studies. The effectiveness data required were obtained from a systematic review of randomized controlled trials. Resource use and cost data were obtained from three sources; the identified randomized controlled trials, a separate review of observational studies and primary data collection. The results of the case studies show that, although simple economic evaluations were possible, issues arose, such as how transferable results are between settings and how appropriate it is to focus on the average patient. The interface between economic evaluation and systematic reviews needs to be further developed in order to ensure that the best available evidence can be used to inform future policy and research.

Physicians in service to the underserved: an analysis of the practice locations of alumni of Western University of Health Sciences College of Osteopathic Medicine of the Pacific, 1982-1995

PURPOSE

To determine how many osteopathic medical graduates (DOs) of the Western University of Health Sciences were practicing in underserved communities.

METHOD

Practice address information was available for 765 of the 850 practicing DO alumni who had graduated from the University from 1982 through 1995. Alumni were categorized as practicing in underserved areas or not, following federally established guidelines; they were also categorized by gender, ethnicity, and medical specialty.

RESULTS

Overall, 20.9% of these 765 alumni were practicing in underserved communities. The percentages of alumni practicing in underserved communities by gender, ethnicity, and specialty were: men, 20.9%; women, 21.0%; Caucasians, 20.5%; Asian Americans, 18.0%; African Americans, 25.0%; Hispanic Americans, 32.1%; Native Americans, 33.3%; primary care physicians, 20.9%; and non-primary care physicians, 20.9%.

CONCLUSIONS

Approximately one in five practicing DO alumni of Western University was practicing in an underserved area. Examining these data by sex, ethnicity, and practice specialization suggested only weak associations between subgroup membership and practice in an underserved area.

Gender bias and the JAMA study: are medical illustration and the A.M.I. politically correct?

The May/June 1996 Association of Medical Illustration News issued an alert to its membership. An article by Kristin Mount raised the spectre of gender bias against women in medical illustration (Mount 1996). She cited the findings of a 1994 research project in the Journal of the American Medical Association. Researchers found female images significantly underrepresented in various medical texts, possibly to the detriment of women. The present article gauges the seriousness of the problem and suggests ways of dealing with it.

Imagery and modality in sentence acquisition by adult males and females

The hypothesis that imagery use by the aged in learning concrete materials is suppressed under visual presentation conditions was investigated in a comparison of acquisition of sentences across three learning trials. Ten men and women in each of three age groups (21.4, 39.7, and 69.5 years) were given five abstract and five concrete sentences under either auditory or visual presentation. It was hypothesized that interference between perceptual and mediational processes would occur when both were dependent on the same store (visual or auditory), and that the oldest group would be most subject to this interference effect with concrete sentences. The results provided support for this hypothesis and led to the further suggestion that the effect of interference was mediated by practice.

The effect of low-cost maintenance medication on the rehospitalization of schizophrenic outpatients

In an effort to determine whether expense is a relevant factor when schizophrenic outpatients discontinue maintenance medication, the authors gave low-cost drugs to 44 subjects, while 46 control subjects paid the retail rate. The unexpected result was that the group receiving low-cost drugs had a significantly higher rate of rehospitalization. The authors suggest that monetary investment on the patient's part may be an important factor in successful drug maintenance.

A comparison of the WISC and WISC-R in a juvenile delinquent population

WISC and WISC-R subtest and IQ scores were compared in two samples of juveniles referred to a large metropolitan juvenile probation department (Ns = 180 and 185, respectively). The samples were equated for age, sex, race, and grade level. Significant differences were found on six of the 10 subtests. There were also significant differences between WISC and WISC-R scores on the Verbal, Performance, and Full Scale scores. In each case the WISC-R score was lower than the WISC score with the exception of the Arithmetic subtest. We conclude from these data that juvenile delinquents score significantly lower on the WISC-R than on the WISC. Psychologists using the WISC-R where the WISC had been previously used should educate their referral sources and other users of scores from the WISC-R to the differences in the test scores between the WISC and WISC-R.