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Gloucester, United Kingdom
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Hischier R.,Assessment Technology Group | Baudin I.,Swiss Federal Office for the Environment Bafu
International Journal of Life Cycle Assessment | Year: 2010

Purpose: Nowadays, there is one television device for every four human beings, making television one of the most popular pieces of electrical and electronic equipment in our society, with the so-called flat-screen technologies gaining more and more market share. For one such technology, the plasma display panel (PDP), no complete life cycle assessment (LCA) studies have existed thus far, and therefore, the question as to their environmental performance, especially as compared with LCD technology, is still open. This paper describes a detailed LCA study of a PDP television, including a first comparison of it with the two competing technologies, the cathode ray tube and the liquid crystal display technologies. Methods: An LCA study from cradle to grave-i.e., from the extraction of the various resources used in the production to the final recycling or disposal activities-has been established taking the complete life cycle of one PDP television as the functional unit. Results: Analysis of the complete life cycle of a PDP television shows that the distribution stage is of no importance. Of the remaining life cycle stages, the importance of the use phase depends on the actual production mix used for the electricity consumed. A fossil-based electricity mix, such as the Union for the Coordination of Transmission of Electricity (UCTE)-mix, causes an impact in the use phase about two times higher than in the production phase. The production phase is dominated by the printed wiring boards and their various components-responsible for more than three quarters of the impact of this first life stage. Last but not least, in the end-of-life (EoL) phase, substantial environmental benefits are possible through a modern recycling system. A comparison of the PDP with competing technologies shows the PDP technology to be the more environmentally friendly one, based on the impact per square-inch of screen. All technologies show thereby a similar picture-production and use having high impacts, distribution being irrelevant, and EoL resulting in an ecological benefit. Conclusions: Hence, it is advisable to use electronic devices such as a PDP television as long as possible, because within the manufacturing stage, the production of the electronics is by far the most important production part. Some of this high environmental impact in electronics can be recovered in an up-to-date recycling system. The second most important life stage is the use phase, which depends on the production mix of the electricity consumed; the more non-renewable sources used for its production, the higher the impact of the use phase will appear. Hence, electronic devices should be used specifically and be turned off when not in use. © 2010 Springer-Verlag.

Samson D.,Washington Technology | Schoelles K.M.,Assessment Technology Group
Journal of General Internal Medicine | Year: 2012

Topic development and structuring a systematic review of diagnostic tests are complementary processes. The goals of a medical test review are to identify and synthesize evidence to evaluate the impacts alternative testing strategies on health outcomes and to promote informed decisionmaking. A common challenge is that the request for a review may state the claim for the test ambiguously. Due to the indirect impact of medical tests on clinical outcomes, reviewers need to identify which intermediate outcomes link a medical test to improved clinical outcomes. In this paper, we propose the use of five principles to deal with challenges: the PICOTS typology (patient population, intervention, comparator, outcomes, timing, setting), analytic frameworks, simple decision trees, other organizing frameworks and rules for when diagnostic accuracy is sufficient. © 2012 Agency for Healthcare Research and Quality (AHRQ).

Whyte S.,Assessment Technology Group
Health technology assessment (Winchester, England) | Year: 2010

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of bevacizumab in combination with fluoropyrimidine-based chemotherapy for the first-line treatment of metastatic colorectal cancer based on the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. Evidence was available in the form of one phase III, multicentre, multinational, randomised, open-label study (NO16966 trial). This two-arm study was originally designed to demonstrate the non-inferiority of oral capecitabine plus oxaliplatin (XELOX) compared with 5-fluorouracil plus folinic acid plus oxaliplatin (FOLFOX)-4 in adult patients with histologically confirmed metastatic colorectal cancer who had not previously been treated. Following randomisation of 634 patients, the open-label study was amended to include a 2 × 2 factorial randomised (partially blinded for bevacizumab) phase III trial with the coprimary objective of demonstrating superiority of bevacizumab in combination with chemotherapy compared with chemotherapy alone. Measured outcomes included overall survival, progression-free survival, response rate, adverse effects of treatment and health-related quality of life. The manufacturer's primary pooled analysis of superiority (using the intention-to-treat population) showed that after a median follow-up of 28 months, the addition of bevacizumab to chemotherapy significantly improved progression-free survival and overall survival compared with chemotherapy alone in adult patients with histologically confirmed metastatic colorectal cancer who were not previously treated [median progression-free survival 9.4 vs 7.7 months (absolute difference 1.7 months); hazard ratio (HR) 0.79, 97.5% confidence interval (CI) 0.72 to 0.87; p = 0.0001; median overall survival 21.2 vs 18.9 months (absolute difference 2.3 months); HR 0.83, 97.5% CI 0.74 to 0.93; p = 0.0019]. The NO16966 trial was of reasonable methodological quality and demonstrated a significant improvement in both progression-free survival and overall survival when bevacizumab was added to XELOX or FOLFOX. However, the size of the actual treatment effect of bevacizumab is uncertain. The ERG believed that the modelling structure employed was appropriate, but highlighted several key issues and areas of uncertainty. At the time of writing, NICE was yet to issue the guidance for this appraisal.

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of rituximab for the first-line treatment of chronic lymphocytic leukaemia (CLL) based upon a review of the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The manufacturer's searches for clinical effectiveness and cost-effectiveness data were appropriate and included all relevant studies. The submission's evidence came from a single, unpublished, well-conducted randomised controlled trial (RCT) comparing rituximab in combination with fludarabine and cyclophosphamide (R-FC) with fludarabine and cyclophosphamide (FC) alone for the first-line treatment of CLL. There was a statistically significant increase in progression-free survival (PFS) with R-FC compared with FC alone {median 39.8 months vs 32.2 months; hazard ratio [HR] 0.56 [95% confidence interval (CI) 0.43 to 0.72]}. However, the initial significant treatment benefit for R-FC compared with FC for overall survival was not maintained at a slightly longer follow-up time [median 25.4 months; adjusted HR 0.72 (95% CI 0.48 to 1.09)]. Response rates, numbers of patients with event-free survival and duration of response all favoured treatment with R-FC. Additional evidence from a mixed-treatment comparison model indicated R-FC to be significantly superior to chlorambucil alone for both PFS and overall and complete response rates. The incidence of grade 3 or 4 adverse events was higher in the R-FC arm (77%) than in the FC arm (62%). Dose modifications were also more frequent in this arm, but this did not lead to differences in treatment discontinuation. Roche used a three-state Markov model (PFS, progressed and death) to model the cost-effectiveness of R-FC compared with FC and chlorambucil alone. The model used a cycle length of 1 month and a lifetime time horizon. The approach taken to modelling was reasonable and the sources and justification of estimates were generally sound. The base-case analysis produced an incremental cost-effectiveness ratio (ICER) of 13,189 pounds per quality-adjusted life-year (QALY) for R-FC versus FC, and 6422 pounds per QALY for the comparison of R-FC versus chlorambucil, suggesting that R-FC is cost-effective at normal willingness-to-pay thresholds. One-way sensitivity analyses produced a range of ICERs from 10,249 pounds to 22,661 pounds per QALY for R-FC versus FC, and 5612 pounds and 6921 pounds per QALY for R-FC versus chlorambucil. Probabilistic sensitivity analysis results matched the deterministic results very closely. However, the sensitivity analysis did not fully investigate the uncertainty associated with differential values across arms or with the structural assumptions of the model, and utility values were not drawn from an empirical study. The NICE guidance issued as a result of the STA states that: Rituximab in combination with fludarabine and cyclophosphamide (R-FC) is recommended as an option for the first-line treatment of chronic lymphocytic leukaemia in people for whom fludarabine in combination with cyclophosphamide (FC) is considered appropriate. Rituximab in combination with chemotherapy agents other than fludarabine and cyclophosphamide is not recommended for the first-line treatment of chronic lymphocytic leukaemia.

Brown M.D.,University of Illinois at Chicago | Feairheller D.L.,Assessment Technology Group
Exercise and Sport Sciences Reviews | Year: 2013

African Americans have an endothelial dysfunction that likely contributes to their high prevalence of hypertension. Endothelial cell (EC) responses to stimuli could play a role in the development of endothelial dysfunction and hypertension. High physiological levels of vascular laminar shear stress can alter EC phenotype profoundly. It is not known whether there are race-dependent EC responses to laminar shear stress. Copyright © 2012 by the American College of Sports Medicine.

Hoyle M.,Assessment Technology Group
PharmacoEconomics | Year: 2011

Economic evaluations of health technologies typically assume constant real drug prices and model only the cohort of patients currently eligible for treatment.It has recently been suggested that, in the UK, we should assume that real drug prices decrease at 4 per annum and, in New Zealand, that real drug prices decrease at 2 per annum and at patent expiry the drug price falls. It has also recently been suggested that we should model multiple future incident cohorts. In this article, the cost effectiveness of drugs is modelled based on these ideas.Algebraic expressions are developed to capture all costs and benefits over the entire life cycle of a new drug. The lifetime of a new drug in the UK, a key model parameter, is estimated as 33 years, based on the historical lifetime of drugs in England over the last 27 years. Under the proposed methodology, cost effectiveness is calculated for seven new drugs recently appraised in the UK. Cost effectiveness as assessed in the future is also estimated. Whilst the article is framed in mathematics, the findings and recommendations are also explained in non-mathematical language. The 'life-cycle correction factor' is introduced, which is used to convert estimates of cost effectiveness as traditionally calculated into estimates under the proposed methodology.Under the proposed methodology, all seven drugs appear far more cost effective in the UK than published. For example, the incremental cost-effectiveness ratio decreases by 46, from £61900 to £33500 per QALY, for cinacalcet versus best supportive care for end-stage renal disease, and by 45, from £31100 to £17000 per QALY, for imatinib versus interferon-α for chronic myeloid leukaemia. Assuming real drug prices decrease over time, the chance that a drug is publicly funded increases over time, and is greater when modelling multiple cohorts than with a single cohort.Using the methodology (compared with traditional methodology) all drugs in the UK and New Zealand are predicted to be more cost effective. It is suggested that the willingness-to-pay threshold should be reduced in the UK and New Zealand. The ranking of cost effectiveness will change with drugs assessed as relatively more cost effective and medical devices and surgical procedures relatively less cost effective than previously thought. The methodology is very simple to implement. It is suggested that the model should be parameterized for other countries. © 2011 Adis Data Information BV. All rights reserved.

Objectives: The expected lifetime of a health technology is a critical parameter in value of information analysis and in two methodologies for cost-effectiveness analysis which have recently been suggested. The first method allows for the possibility that a superior technology will become available in the future. The second advocates modeling both the prevalent and all future incident patient cohorts. Unfortunately, for value of information analysis, the period of time over which information about the decision problem would be useful is very uncertain, and existing estimates are seemingly arbitrary. Furthermore, there is very little literature on the historical lifetimes of technologies. Here, I quantify and analyze the historical lifetimes of drugs in England. I then apply this information to inform the value of further research and the cost-effectiveness of health technologies. Methods: A Weibull regression model was fitted to the historical drug lifetimes of 455 drugs. These represented all British National Formulary drugs in England which were launched from 1981 to 2007, and which did not have very low sales volumes. Results: The mean drug lifetime was 57 years (95% confidence interval 39-79 years), and the median was 46 years (35-60 years). Drugs with low sales volumes tended to have shorter lifetimes. Under certain assumptions, the ratio of population level to per-year expected value of information is 21. Drug lifetimes are used to parameterize the two models of cost-effectiveness. Conclusions: The distribution function of the historical lifetimes of drugs can inform suitable time horizons for: 1) value of information; and 2) cost-effectiveness analyses related to drugs. © 2010, International Society for Pharmacoeconomics and Outcomes Research (ISPOR).

Cochrane reviews are one of the best known and most trusted sources of evidence-based information in health care. While steps have been taken to make Cochrane intervention reviews accessible to a diverse readership, little is known about the accessibility of the newcomer to the Cochrane library: diagnostic test accuracy reviews (DTARs). The current qualitative study explored how healthcare decision makers, who varied in their knowledge and experience with test accuracy research and systematic reviews, read and made sense of DTARs. A purposive sample of clinicians, researchers and policy makers (n = 21) took part in a series of think-aloud interviews, using as interview material the first three DTARs published in the Cochrane library. Thematic qualitative analysis of the transcripts was carried out to identify patterns in participants' 'reading' and interpretation of the reviews and the difficulties they encountered. Participants unfamiliar with the design and methodology of DTARs found the reviews largely inaccessible and experienced a range of difficulties stemming mainly from the mismatch between background knowledge and level of explanation provided in the text. Experience with systematic reviews of interventions did not guarantee better understanding and, in some cases, led to confusion and misinterpretation. These difficulties were further exacerbated by poor layout and presentation, which affected even those with relatively good knowledge of DTARs and had a negative impact not only on their understanding of the reviews but also on their motivation to engage with the text. Comparison between the readings of the three reviews showed that more accessible presentation, such as presenting the results as natural frequencies, significantly increased participants' understanding. The study demonstrates that authors and editors should pay more attention to the presentation as well as the content of Cochrane DTARs, especially if the reports are aimed at readers with various levels of background knowledge and experience. It also raises the question as to the anticipated target audience of the reports and suggests that different groups of healthcare decision-makers may require different modes of presentation.

Background Patients with treatment-resistant depression (TRD) are those with major depressive disorder that has not responded adequately to treatment. The causes of depression are not fully understood, although there is evidence to suggest that depression is a complex interaction among biological, genetic, psychosocial and environmental factors. Strategies available for the treatment of patients with TRD include pharmacological, non-pharmacological, and psychological and psychosocial interventions. Pharmacological treatment options include switching to a different antidepressant, the addition of another antidepressant of a different class, or use of an augmenting agent, such as anticonvulsants, lithium or atypical antipsychotics (AAPs). However, there is limited evidence available on the effectiveness of these strategies in the treatment of TRD. Objectives To estimate the clinical effectiveness and cost-effectiveness of augmentation of selective serotonin reuptake inhibitor (SSRI) antidepressant therapy with either lithium or an AAP drug in the management of people with treatment-resistant unipolar depression, defined as failure to respond to two or more antidepressant drugs in their current episode of depression. Data sources Databases searched were Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, MEDLINE, PsycINFO and NHS Economic Evaluation Database (NHS EED). All databases were searched from inception to August 2011. Additional data were obtained from manufacturers. Review methods Systematic reviews of studies evaluating clinical effectiveness, economic analyses and quality of life (QoL) were executed. Quality assessment according to predefined criteria was undertaken independently by two reviewers. Pairwise meta-analyses and mixed-treatment comparisons (MTCs) using both fixed- and random-effects models were undertaken based on intention-to-treat analyses. A probabilistic de novo mathematical model was developed to synthesise the available data on costs and clinical outcomes from the UK NHS perspective over a 1-year time horizon (8 weeks of acute treatment captured by a decision tree and 10 months of maintenance treatment captured by a Markov model). Results Twelve randomised controlled trials (RCTs) were identified in the review of clinical effectiveness literature; 10 considered SSRI + AAP compared with SSRI + placebo/no treatment, one considered SSRI + AAP compared with SSRI + lithium and one considered SSRI + lithium compared with SSRI + placebo. The RCTs included in the primary analyses used fluoxetine as the background SSRI and olanzapine as the AAP. Results of the MTC showed a non-significant trend in favour of lithium augmentation for response [lithium a priori odds ratio (OR) 1.29; 95% credible interval (CrI) 0.11 to 5.32; lithium post hoc OR 4.15; 95% CrI 0.25 to 20.34 (the trial informing the comparison with lithium reported response using two different definitions)], mean change in Montgomery-Åsberg Depression Rating Scale score from baseline (mean difference - 1.47, 95% CrI - 9.10 to 6.41) and all-cause withdrawals (OR 0.74, 95% CrI 0.10 to 2.66). Four economic evaluations (none directly addressing the review question) and 17 studies that reported on QoL were identified and summarised in narrative reviews. The results of the de novo modelling indicate that augmentation of SSRI with lithium dominates augmentation of an SSRI with AAP (i.e. it resulted in cost savings of £905 per person per year and generated more health benefits, estimated to be 0.03 quality-adjusted life-years). However, sensitivity analyses showed that the model was highly sensitive to changes in acute treatment efficacy (response and remission) or discontinuation. The model was not sensitive to changes in other parameters. Limitations In patients with TRD, there is a lack of direct evidence comparing the clinical effectiveness of augmenting an SSRI with an AAP compared with augmenting with lithium. RCTs were identified which facilitated comparison of adding AAP with adding lithium via a MTC. However, variations in the definitions of response implemented in the RCTs, together with differences in patient baseline characteristics across RCTs, introduce bias into the analysis. The direction and extent of the bias is uncertain. Conclusions Augmentation of SSRIs with lithium or AAP is likely to be beneficial in people with TRD. Clinical evaluation based on the limited evidence identified in this research indicates no statistically significant difference between the two augmentation strategies. Cost-effectiveness analyses suggest that augmentation with lithium is less expensive and more effective than augmentation with AAP. However, the uncertainty in the clinical estimates of discontinuation and treatment response is reflected in the model results. A RCT comparing the two augmentation strategies, reporting relevant outcomes, including QoL, is needed.

Main C.,Assessment Technology Group
The Cochrane database of systematic reviews | Year: 2013

Evidence from systematic reviews of observational studies suggest that hormone replacement therapy (HT) may have beneficial effects in reducing the incidence of cardiovascular disease (CVD) events in post-menopausal women. This is an updated version of a Cochrane review first published in 2005 (Gabriel-Sanchez 2005). To assess the effects of HT for the prevention of CVD in post-menopausal women, and whether there are differential effects between use of single therapy alone compared to combination HT and use in primary or secondary prevention. We searched the following databases to April 2010: Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library, MEDLINE, EMBASE and LILACS. Randomised controlled trials (RCTs) of women comparing orally administered HT with placebo with a minimum of six-months follow-up. Two authors independently assessed study quality and extracted data. Risk Ratios (RR) with 95% confidence intervals were calculated for each outcome. Results were combined using fixed-effect meta-analyses, and where possible, further stratified analyses conducted to assess the effect of time on treatment. Additionally, univariate meta-regression analyses were undertaken to assess whether length of trial follow-up, single or combination treatment, or whether treatment for primary or secondary prevention were potential predictors for a number of CVD outcomes in the trials. Four new trials were identified through the update; one trial included in the previous review was excluded. Therefore the review included 13 trials with a total of 38,171 post-menopausal women. Overall, single and combination HT in both primary and secondary prevention conferred no protective effects for all cause mortality, CVD death, non-fatal MI, or angina. There were no significant differences in the number of coronary artery by-pass procedures or angioplasties performed between the trial arms. However there was an increased risk of stroke for both primary and secondary prevention when combination and single HT was combined, RR 1.26 (95% CI 1.11 to 1.43), in venous thromboembolic events, RR 1.89 (95% CI 1.58 to 2.26) and in pulmonary embolism RR 1.84 (95% CI 1.42 to 2.37) relative to placebo. The associated numbers needed-to-harm (NNH) were 164, 109 and 243 for stroke, venous thromboembolism and pulmonary embolism respectively. Treatment with HT in post-menopausal women for either primary or secondary prevention of CVD events is not effective, and causes an increase in the risk of stroke, and venous thromboembolic events. HT should therefore only be considered for women seeking relief from menopausal symptoms. Short-term HT treatment should be at the lowest effective dose, and used with caution in women with predisposing risk factors for CVD events.

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