Cost-effectiveness of outpatient parenteral antibiotic therapy: a simulation modelling approach.

Objectives: In the UK, patients who require intravenous antimicrobial (IVA) treatment may receive this in the community through outpatient parenteral antimicrobial therapy (OPAT) services. Services include: IVA administration at a hospital outpatient clinic (HO); IVA administration at home by a general nurse (GN) or a specialist nurse (SN); or patient self-administered (SA) IVA administration following training. There is uncertainty regarding which OPAT services represent value for money; this study aimed to estimate their cost-effectiveness. Methods: A cost-effectiveness decision-analytic model was developed using a simulation technique utilizing data from hospital records and a systematic review of the literature. The model estimates cost per QALY gained from the National Health Service (NHS) perspective for short- and long-term treatment of infections and service combinations across these. Results: In short-term treatments, HO was estimated as the most effective (0.7239 QALYs), but at the highest cost (£973). SN was the least costly (£710), producing 0.7228 QALYs. The combination between SN and HO was estimated to produce 0.7235 QALYs at a cost of £841. For long-term treatments, SN was the most effective (0.677 QALYs), costing £2379, while SA was the least costly at £1883, producing 0.666 QALYs. A combination of SA and SN was estimated to produce 0.672 QALYs at a cost of £2128. Conclusions: SN and SA are cost-effective for short- and long-term treatment of infections, while combining services may represent the second-best alternative for OPAT in the UK.

Clinical and cost-effectiveness, safety and acceptability of community intravenous antibiotic service models: CIVAS systematic review.

OBJECTIVE: Evaluate evidence of the efficacy, safety, acceptability and cost-effectiveness of outpatient parenteral antimicrobial therapy (OPAT) models. DESIGN: A systematic review. DATA SOURCES: MEDLINE, EMBASE, CINAHL, Cochrane Library, National Health Service (NHS) Economic Evaluation Database (EED), Research Papers in Economics (RePEc), Tufts Cost-Effectiveness Analysis (CEA) Registry, Health Business Elite, Health Information Management Consortium (HMIC), Web of Science Proceedings, International Pharmaceutical Abstracts, British Society for Antimicrobial Chemotherapy website. Searches were undertaken from 1993 to 2015. STUDY SELECTION: All studies, except case reports, considering adult patients or practitioners involved in the delivery of OPAT were included. Studies combining outcomes for adults and children or non-intravenous (IV) and IV antibiotic groups were excluded, as were those focused on process of delivery or clinical effectiveness of 1 antibiotic over another. Titles/abstracts were screened by 1 reviewer (20% verified). 2 authors independently screened studies for inclusion. RESULTS: 128 studies involving >60 000 OPAT episodes were included. 22 studies (17%) did not indicate the OPAT model used; only 29 involved a comparator (23%). There was little difference in duration of OPAT treatment compared with inpatient therapy, and overall OPAT appeared to produce superior cure/improvement rates. However, when models were considered individually, outpatient delivery appeared to be less effective, and self-administration and specialist nurse delivery more effective. Drug side effects, deaths and hospital readmissions were similar to those for inpatient treatment, but there were more line-related complications. Patient satisfaction was high, with advantages seen in being able to resume daily activities and having greater freedom and control. However, most professionals perceived challenges in providing OPAT. CONCLUSIONS: There were no systematic differences related to the impact of OPAT on treatment duration or adverse events. However, evidence of its clinical benefit compared with traditional inpatient treatment is lacking, primarily due to the dearth of good quality comparative studies. There was high patient satisfaction with OPAT use but the few studies considering practitioner acceptability highlighted organisational and logistic barriers to its delivery.

Community IntraVenous Antibiotic Study (CIVAS): protocol for an evaluation of patient preferences for and cost-effectiveness of community intravenous antibiotic services.

INTRODUCTION: Outpatient parenteral antimicrobial therapy (OPAT) is used to treat a wide range of infections, and is common practice in countries such as the USA and Australia. In the UK, national guidelines (standards of care) for OPAT services have been developed to act as a benchmark for clinical monitoring and quality. However, the availability of OPAT services in the UK is still patchy and until quite recently was available only in specialist centres. Over time, National Health Service (NHS) Trusts have developed OPAT services in response to local needs, which has resulted in different service configurations and models of care. However, there has been no robust examination comparing the cost-effectiveness of each service type, or any systematic examination of patient preferences for services on which to base any business case decision. METHODS AND ANALYSIS: The study will use a mixed methods approach, to evaluate patient preferences for and the cost-effectiveness of OPAT service models. The study includes seven NHS Trusts located in four counties. There are five inter-related work packages: a systematic review of the published research on the safety, efficacy and cost-effectiveness of intravenous antibiotic delivery services; a qualitative study to explore existing OPAT services and perceived barriers to future development; an economic model to estimate the comparative value of four different community intravenous antibiotic services; a discrete choice experiment to assess patient preferences for services, and an expert panel to agree which service models may constitute the optimal service model(s) of community intravenous antibiotics delivery. ETHICS AND DISSEMINATION: The study has been approved by the NRES Committee, South West-Frenchay using the Proportionate Review Service (ref 13/SW/0060). The results of the study will be disseminated at national and international conferences, and in international journals.

What is the value of routinely testing full blood count, electrolytes and urea, and pulmonary function tests before elective surgery in patients with no apparent clinical indication and in subgroups of patients with common comorbidities: a systematic review of the clinical and cost-effective literature.

BACKGROUND: The evidence base which supported the National Institute for Health and Clinical Excellence (NICE) published Clinical Guideline 3 was limited and 50% was graded as amber. However, the use of tests as part of pre-operative work-up remains a low-cost but high-volume activity within the NHS, with substantial resource implications. The objective of this study was to identify, evaluate and synthesise the published evidence on the clinical effectiveness and cost-effectiveness of the routine use of three tests, full blood counts (FBCs), urea and electrolytes tests (U&Es) and pulmonary function tests, in the pre-operative work-up of otherwise healthy patients undergoing minor or intermediate surgery in the NHS. OBJECTIVE: The aims of this study were to estimate the clinical effectiveness and cost-effectiveness of routine pre-operative testing of FBC, electrolytes and renal function and pulmonary function in adult patients classified as American Society of Anaesthesiologists (ASA) grades 1 and 2 undergoing elective minor (grade 1) or intermediate (grade 2) surgical procedures; to compare NICE recommendations with current practice; to evaluate the cost-effectiveness of mandating or withdrawing each of these tests in this patient group; and to identify the expected value of information and whether or not it has value to the NHS in commissioning further primary research into the use of these tests in this group of patients. DATA SOURCES: The following electronic bibliographic databases were searched: (1) BIOSIS; (2) Cumulative Index to Nursing and Allied Health Literature; (3) Cochrane Database of Systematic Reviews; (4) Cochrane Central Register of Controlled Trials; (5) EMBASE; (6) MEDLINE; (7) MEDLINE In-Process & Other Non-Indexed Citations; (8) NHS Database of Abstracts of Reviews of Effects; (9) NBS Health Technology Assessment Database; and (10) Science Citation Index. To identify grey and unpublished literature, the Cochrane Register of Controlled Trials, National Research Register Archive, National Institute for Health Research Clinical Research Network Portfolio database and the Copernic Meta-search Engine were searched. A large routine data set which recorded the results of tests was obtained from Leeds Teaching Hospitals Trust. REVIEW METHODS: A systematic review of the literature was carried out. The searches were undertaken in March to April 2008 and June 2009. Searches were designed to retrieve studies that evaluated the clinical effectiveness and cost-effectiveness of routine pre-operative testing of FBC, electrolytes and renal function and pulmonary function in the above group of patients. A postal survey of current practice in testing patients in this group pre-operatively was undertaken in 2008. An exemplar cost-effectiveness model was constructed to demonstrate what form this would have taken had there been sufficient data. A large routine data set that recorded the results of tests was obtained from Leeds Teaching Hospitals Trust. This was linked to individual patient data with surgical outcomes, and regression models were estimated. RESULTS: A comprehensive and systematic search of both the clinical effectiveness and cost-effectiveness literature identified a large number of potentially relevant studies. However, when these studies were subjected to detailed review and quality assessment, it became clear that the literature provides no evidence on the clinical effectiveness and cost-effectiveness of these specific tests in the specific patient groups. The postal survey had a 17% response rate. Results reported that in ASA grade 1, patients aged < 40 years with no comorbidities undergoing minor surgery did not have routine tests for FBC, electrolytes and renal function and pulmonary function. The results from the regression model showed that the frequency of test use was not consistent with the hypothesis of their routine use. FBC tests were performed in only 58% of patients in the data set and U&E testing was carried out in only 57%. LIMITATIONS: Systematic searches of the clinical effectiveness and cost-effectiveness literature found that there is no evidence on the clinical effectiveness or cost-effectiveness of these tests in this specific clinical context for the NHS. A survey of NHS hospitals found that respondent trusts were implementing current NICE guidance in relation to pre-operative testing generally, and a de novo analysis of routine data on test utilisation and post-operative outcome found that the tests were not be used in routine practice; rather, use was related to an expectation of a more complex clinical case. The paucity of published evidence is a limitation of this study. The studies included relied on non-UK health-care systems data, which may not be transferable. The inclusion of non-randomised studies is associated with an increased risk of bias and confounding. Scoping work to establish the likely mechanism of action by which tests would impact upon outcomes and resource utilisation established that the cause of an abnormal test result is likely to be a pivotal determinant of the cost-effectiveness of a pre-operative test and therefore evaluations would need to consider tests in the context of the underlying risk of specific clinical problems (i.e. risk guided rather than routine use). CONCLUSIONS: The time of universal utilisation of pre-operative tests for all surgical patients is likely to have passed. The evidence we have identified, though weak, indicates that tests are increasingly utilised in patients in whom there is a reason to consider an underlying raised risk of a clinical abnormality that should be taken into account in their clinical management. It is likely that this strategy has led to substantial resource savings for the NHS, although there is not a published evidence base to establish that this is the case. The total expenditure on pre-operative tests across the NHS remains significant. Evidence on current practice indicates that clinical practice has changed to such a degree that the original research question is no longer relevant to UK practice. Future research on the value of these tests in pre-operative work-up should be couched in terms of the clinical effectiveness and cost-effectiveness in the identification of specific clinical abnormalities in patients with a known underlying risk. We suggest that undertaking a multicentre study making use of linked, routinely collected data sets would identify the extent and nature of pre-operative testing in this group of patients. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Cost-effectiveness of screening high-risk HIV-positive men who have sex with men (MSM) and HIV-positive women for anal cancer.

BACKGROUND: Anal cancer is uncommon and predominantly a disease of the elderly. The human papillomavirus (HPV) has been implicated as a causal agent, and HPV infection is usually transmitted sexually. Individuals who are human immunodeficiency virus (HIV)-positive are particularly vulnerable to HPV infections, and increasing numbers from this population present with anal cancer. OBJECTIVE: To estimate the cost-effectiveness of screening for anal cancer in the high-risk HIV-positive population [in particular, men who have sex with men (MSM), who have been identified as being at greater risk of the disease] by developing a model that incorporates the national screening guidelines criteria. DATA SOURCES: A comprehensive literature search was undertaken in January 2006 (updated in November 2006). The following electronic bibliographic databases were searched: Applied Social Sciences Index and Abstracts (ASSIA), BIOSIS previews (Biological Abstracts), British Nursing Index (BNI), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, NHS Database of Abstracts of Reviews of Effects (DARE), NHS Health Technology Assessment (HTA) Database, PsycINFO, Science Citation Index (SCI), and Social Sciences Citation Index (SSCI). STUDY SELECTION: Published literature identified by the search strategy was assessed by four reviewers. Papers that met the inclusion criteria contained the following: data on population incidence, effectiveness of screening, health outcomes or screening and/or treatment costs; defined suitable screening technologies; prospectively evaluated tests to detect anal cancer. Foreign-language papers were excluded. Searches identified 2102 potential papers; 1403 were rejected at title and a further 493 at abstract. From 206 papers retrieved, 81 met the inclusion criteria. A further treatment paper was added, giving a total of 82 papers included. DATA EXTRACTION: Data from included studies were extracted into data extraction forms by the clinical effectiveness reviewer. To analyse the cost-effectiveness of screening, two decision-analytical models were developed and populated. RESULTS: The reference case cost-effectiveness model for MSM found that screening for anal cancer is very unlikely to be cost-effective. The negative aspects of screening included utility decrements associated with false-positive results and with treatment for high-grade anal intraepithelial neoplasia (HG-AIN). Sensitivity analyses showed that removing these utility decrements improved the cost-effectiveness of screening. However, combined with higher regression rates from low-grade anal intraepithelial neoplasia (LG-AIN), the lowest expected incremental cost-effectiveness ratio remained at over 44,000 pounds per quality-adjusted life-year (QALY) gained. Probabilistic sensitivity analysis showed that no screening retained over 50% probability of cost-effectiveness to a QALY value of 50,000 pounds. The screening model for HIV-positive women showed an even lower likelihood of cost-effectiveness, with the most favourable sensitivity analyses reporting an incremental cost per QALY of 88,000 pounds. LIMITATIONS: Limited knowledge is available about the epidemiology and natural history of anal cancer, along with a paucity of good-quality evidence concerning the effectiveness of screening. CONCLUSIONS: Many of the criteria for assessing the need for a screening programme were not met and the cost-effectiveness analyses showed little likelihood that screening any of the identified high-risk groups would generate health improvements at a reasonable cost. Further studies could assess whether the screening model has underestimated the impact of anal cancer, the results of which may justify an evaluative study of the effects of treatment for HG-AIN.

A preliminary model-based assessment of the cost-utility of a screening programme for early age-related macular degeneration.

OBJECTIVES: To estimate the cost-effectiveness of screening for age-related macular degeneration (AMD) by developing a decision analytic model that incorporated and assessed all of the National Screening Committee criteria. A further objective was to identify the major areas of uncertainty in the model, and so inform future research priorities in this disease area. DATA SOURCES: Major databases were searched in March 2004 and updated in January 2005. REVIEW METHODS: Systematic literature reviews covered the epidemiology and natural history of AMD, the screening and treatment effectiveness and health-related quality of life relating to AMD. A hybrid cohort-individual sampling model was implemented to describe the range of pathways between the incidence of age-related maculopathy (ARM) and death via clinical presentation and treatment at different stages of the disease. As significant shortfalls in the data available from the literature were apparent, so a range of primary data sources were also used to populate the model. To obtain estimates for the value of parameters deemed to be within an expert's remit, data describing some parameters were elicited from relevant experts. The data identified informed probability distributions describing the uncertainty around the model parameters. To incorporate joint parameter uncertainty (i.e. correlations between parameters), the AMD natural history model was calibrated probabilistically. Randomly sampled sets of input parameters were assigned weights representing the accuracy of their predictions of a set of observed model outputs. The analysis of the AMD screening model estimated the costs, numbers of quality-adjusted life-years (QALYs) and cases of blindness in a general population sample of 50-year-olds over the remainder of their lifetime, for 16 alternative screening options (including no screening). The reference case analysis incorporated current treatment options of laser photocoagulation and photodynamic therapy. Sensitivity analyses describing six alternative sets of intervention strategies, based on horizon scanning of potential future treatments for AMD, were also undertaken. RESULTS: There remains significant uncertainty about whether any form of screening for AMD is cost-effective. However, annual screening from age 60 years seems to provide the highest mean net benefits, but this is based on a cost-effectiveness estimate that has very poor precision (high levels of uncertainty). The probabilistic sensitivity analysis shows that the 95% credible interval for annual screening from age 60 years ranges from this option dominating the previous option to an incremental cost per QALY of over 0.5 million pounds sterling. Plotting a cost-effectiveness acceptability frontier shows that although annual screening from age 60 years has the highest net benefits at a value of QALY of 30,000 pounds sterling, the associated probability of this option being the most cost-effective option is only around 20%. The sensitivity analyses around potential future treatment options indicate that screening may become more cost-effective with the new treatments. CONCLUSIONS: The conclusions focus on the interpretation of the results from the perspective of defining the major areas of uncertainty, which were defined as disease progression, rates of clinical presentation, screening test and optician effectiveness, treatment effectiveness, and costs of blindness. Future research may be best targeted at assessing how routine data may be used to describe clinical presentation rates of ARM. Other potential studies include a pilot study of the effectiveness of screening and opticians' referral patterns for AMD and a costing study of blindness as a continuum of association with deterioration in vision.

The clinical effectiveness and cost-effectiveness of screening programmes for amblyopia and strabismus in children up to the age of 4-5 years: a systematic review and economic evaluation.

OBJECTIVES: To estimate the cost-effectiveness of screening for amblyopia and strabismus in children aged up to 4-5 years, also identifying the major areas of uncertainty and so inform future research priorities in this disease area. DATA SOURCES: Major electronic databases were searched in January 2006. REVIEW METHODS: Systematic literature reviews were undertaken to determine the prevalence and natural history, the screening methods, the effectiveness of treatment options and health-related quality of life issues relating to amblyopia and strabismus. The review of treatment interventions was restricted to high-quality reviews, meta-analyses and guidelines. The data derived from the review informed the structure and implementation of the decision-analytic model. RESULTS: The amblyopia screening model was analysed in detail to estimate the cost and effects of six alternative screening options comprising screening at different ages (3, 4 and 5 years) and using alternative sets of tests (visual acuity testing and the cover tests, with and without autorefraction). The reference case results showed that screening programmes that included autorefraction dominated screening programmes without autorefraction. Analyses based on the cost per case of amblyopia prevented showed screening at either 3 or 4 years prevented additional cases at a low absolute cost (3000-6000 pounds sterling). However, when these results were extrapolated to estimate the cost per quality-adjusted life-year (QALY) gained, the reference case analysis found that no form of screening is likely to be cost-effective at currently accepted values of a QALY. The wide-ranging sensitivity analyses found that the results were robust to most parameter changes. The only parameter that radically affected the results was the utility effect of loss of vision in one eye. No direct evidence of a utility effect was identified and the reference case assumed no effect. When a small effect is assumed (a reduction in utility of 2%), the incremental cost per QALY gained becomes extremely attractive for screening at both 3 and at 4 years. The expected value of perfect information was shown to be large when the unilateral vision loss utility parameter was allowed to vary, but not when it was kept constant at zero. CONCLUSIONS: The results show that the cost-effectiveness of screening for amblyopia is dependent on the long-term utility effects of unilateral vision loss. There is limited evidence on any such effect, although our subjective interpretation of the available literature is that the utility effects are likely to be minimal. Any utility study investigating such effects would need to be careful to avoid introducing bias. The reference case model did not represent potential treatment-related utility effects, primarily due to an increased probability of treated children being bullied at school. The evidence indicates that this may be a problem, and additional sensitivity analyses show that small utility decrements from bullying would improve the cost-effectiveness of early screening significantly. A prospective study of the utility effects of bullying would usefully inform the analysis, although such a study would need to be carefully planned in order to distinguish whether the overall incidence of bullying decreases with reduced school-age treatment, or whether it is displaced to other children.

Determinants of health related quality of life and health state utility in patients with age related macular degeneration: the association of contrast sensitivity and visual acuity.

BACKGROUND: There has been increasing interest in the use of measures of health related quality of life (HRQoL) and health state utility values in Age Related Macular Degeneration (ARMD). Visual acuity has been found to be an important determinant of such measures in previous studies. More recently, another measure of visual impairment, contrast sensitivity has received considerable attention. We designed a study to examine whether the contribution of contrast sensitivity in explaining HRQoL and health utilities over and above that of visual acuity. METHODS: 209 patients with unilateral or bilateral ARMD were recruited into a cross-sectional study of patients from a large teaching hospital. Patients underwent visual tests (near and distant visual acuity, contrast sensitivity) and completed a vision function questionnaire, the VF-14, HUI3, and time trade-off. RESULTS: Using multivariate regression analysis, the study revealed that contrast sensitivity remained a statistically significant predictor of all outcome measures even when visual acuity was included. This result was supported by the correlation coefficients between measures. CONCLUSIONS: The measurement of contrast sensitivity appears to be better related to a person's HRQoL and health utility. Future studies should consider incorporating contrast sensitivity in addition to visual acuity. Studies, in particular economic evaluations, may underestimate the effect of treatment unless contrast sensitivity is considered.

Clinical effectiveness and cost-effectiveness of pioglitazone and rosiglitazone in the treatment of type 2 diabetes: a systematic review and economic evaluation.

OBJECTIVES: To evaluate the use of pioglitazone and rosiglitazone, in terms of both clinical and cost-effectiveness in the treatment of type 2 diabetes. DATA SOURCES: Electronic databases and the reference lists of relevant articles, in addition 14 health services research-related resources were consulted via the Internet. REVIEW METHODS: A systematic review of the literature, involving a range of databases, was performed to identify all papers relating to the glitazones. The methodological quality of the included randomised controlled trials (RCTs) was assessed using the Jadad method. A generic proforma for the critical appraisal of modelling studies in health economics was used in systematically reviewing the economic assessment studies identified. This was supplemented by a detailed review of the disease-specific factors within the studies. Where possible, key outcomes were compared. Readers should note that information from the sponsor's submission was submitted in confidence to the National Institute for Clinical Excellence (NICE). Such information was made available to the NICE Appraisals Committee, but has been removed from this version of the report. RESULTS: Of the 1272 studies identified, nine studies met the inclusion criteria. The clinical evidence available showed that glitazones reduce glycosylated haemoglobin by approximately 1%, and are more effective at higher doses than at lower doses. Glitazone treatment is associated with weight gain. No published data were available on the long-term effects of glitazone use. No prospective RCTs were found comparing pioglitazone to rosiglitazone, but the available evidence indicated that the two treatments had similar effects. There are no published economic studies on either pioglitazone or rosiglitazone. Economic evaluations for both glitazones were provided by the manufacturers. Sensitivity analyses undertaken by the assessment team suggest that the cost per quality-adjusted life-year (QALY) of rosiglitazone is most sensitive to dosage and treatment effect, that is, the effect of rosiglitazone on beta-cell function and insulin sensitivity. In the two scenarios where rosiglitazone is compared with metformin and sulfonylurea combination therapy, the cost-effectiveness of rosiglitazone switches from around 10,000 pounds per QALY to being dominated by the comparator strategy. Since the baseline estimate of cost-effectiveness is not robust to changes in the treatment effect and is reliant on the many assumptions included within the metabolic and long-term economic models, caution should be used in interpreting the baseline result. CONCLUSIONS: The clinical evidence available showed that glitazones can reduce glycosylated haemoglobin; however there were no peer-reviewed data available on the long-term effects of their use or any prospective RCTs found comparing pioglitazone with rosiglitazone. No published economic studies on either pioglitazone or rosiglitazone were found, although sensitivity analyses undertaken by the assessment team suggest that the cost per QALY of rosiglitazone is most sensitive to dosage and treatment effect. It is suggested that research already undertaken in this area should be published, preferably in peer-reviewed journals. Direct head-to-head comparisons of the glitazones in combination with metformin or sulfonylurea would be helpful. The current licence arrangements do not allow for routine use of the glitazones in triple oral combination therapy or in combination with insulin. Evidence is emerging of use of the glitazones within such combinations; therefore, prospective RCTs would be useful. These studies could examine short-term transition strategies and longer term management. The impact of the glitazones in delaying transfer to insulin and the impact on long-term outcomes should also be considered for investigation.

Extended scope of nursing practice: a multicentre randomised controlled trial of appropriately trained nurses and pre-registration house officers in pre-operative assessment in elective general surgery.

OBJECTIVES: (1) To determine whether pre-operative assessment carried out by an appropriately trained nurse (ATN) is equivalent in quality to that carried out by a pre-registration house officer (PRHO). (2) To assess whether pre-assessments carried out by ATNs and PRHOs are equivalent in terms of cost. (3) To determine whether assessments carried out by ATNs are acceptable to patients. (4) To investigate the quality of communication between senior medical staff and ATNs. DESIGN: The study design was principally a prospective randomised equivalence trial but was accompanied by additional qualitative assessment of patient and staff perceptions, and an economic evaluation. SETTING: The study was carried out at four NHS hospitals, three of which were teaching hospitals, in three NHS Trusts in Southampton, Sheffield and Doncaster. SUBJECTS: All patients attending at one site for assessment prior to general anaesthetic for elective general, vascular, urological or breast surgery were potentially included in the study. Of 1907 patients who were randomised, 1874 completed the study with a full evaluation. INTERVENTIONS: The intervention consisted of a pre-operative assessment carried out by either an ATN or a PRHO. Of the patients who completed the study with a full evaluation, 926 patients were randomised to the PRHO arm of the trial and 948 to the ATN arm. Three ATNs took part in the study, one from each centre, together with a total of 87 PRHOs. MAIN OUTCOME MEASURES: Immediately following the initial assessment of a patient by a PRHO or an ATN, one of a number of clinical research fellows, all specialist registrars in anaesthetics, repeated the assessment and recorded it on a study form, together with a list of investigations required. The clinical research fellow then evaluated the competency of the initial assessor by comparing the quality of their assessment with their own. Any deficiencies in ordering of investigations and referral to other specialities were met in order to maximise patient care. Three areas of ATN and PRHO performance were judged separately, history taking, examination and ordering of tests, and each was graded into one of four categories, the most important of which was under-assessment, which would possibly have affected peri-operative management. In the case of ordering of tests, it was possible to have both over- and under-assessed a patient on different tests. RESULTS: The pre-operative assessments carried out by the ATNs were essentially equivalent to those performed by the PRHOs in terms of under-assessment that might possibly have affected peri-operative management, although there was variation between the ATNs in terms of the quality of history taking. This may be related to the low number of patients seen at one study site. PRHOs ordered significantly more unnecessary tests than the ATNs. The substitution of ATNs for PRHOs was calculated to be cost neutral. The results of the qualitative assessment showed that the use of ATNs for pre-operative assessment was acceptable to patients; however, there was no evidence that communication between senior medical staff and those carrying out pre-operative assessments was improved by their introduction. CONCLUSIONS: This study demonstrated no reason to inhibit the development of fully nurse-led pre-operative assessment, provided that the nurses are appropriately trained and maintain sufficient workload to retain skills. CONCLUSIONS--IMPLICATIONS FOR THE HEALTH SERVICE: ATNs provide an acceptable and efficient alternative to PRHOs for the purposes of routine pre-operative assessment. Consideration will have to be given, however, to the positions of these nurses within the surgical team, and also to their career structure. CONCLUSIONS--RECOMMENDATIONS FOR FUTURE RESEARCH: Further research is needed in the following areas: (1) the extent and type of training needed for nurses undertaking the pre-operative assessment role; (2) the use, costs and benefits of routine pre-operative testing.