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1.
Eye (Lond) ; 31(7): 995-1007, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28282065

RESUMO

We conducted a systematic review of the accuracy of fundus autofluorescence (FAF) imaging for diagnosing and monitoring retinal conditions. Searches in November 2014 identified English language references. Sources included MEDLINE, EMBASE, the Cochrane Library, Web of Science, and MEDION databases; reference lists of retrieved studies; and internet pages of relevant organisations, meetings, and trial registries. For inclusion, studies had to report FAF imaging accuracy quantitatively. Studies were critically appraised using QUADAS risk of bias criteria. Two reviewers conducted all review steps. From 2240 unique references identified, eight primary research studies met the inclusion criteria. These investigated diagnostic accuracy of FAF imaging for choroidal neovascularisation (one study), reticular pseudodrusen (three studies), cystoid macular oedema (two studies), and diabetic macular oedema (two studies). Diagnostic sensitivity of FAF imaging ranged from 32 to 100% and specificity from 34 to 100%. However, owing to methodological limitations, including high and/or unclear risks of bias, none of these studies provides conclusive evidence of the diagnostic accuracy of FAF imaging. Study heterogeneity precluded meta-analysis. In most studies, the patient spectrum was not reflective of those who would present in clinical practice and no studies adequately reported whether FAF images were interpreted consistently. No studies of monitoring accuracy were identified. An update in October 2016, based on MEDLINE and internet searches, identified four new studies but did not alter our conclusions. Robust quantitative evidence on the accuracy of FAF imaging and how FAF images are interpreted is lacking. We provide recommendations to address this.


Assuntos
Monitorização Fisiológica/métodos , Imagem Óptica/métodos , Retina/diagnóstico por imagem , Doenças Retinianas/diagnóstico , Fundo de Olho , Humanos , Reprodutibilidade dos Testes
2.
Crit Rev Food Sci Nutr ; 55(7): 1026-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25191830

RESUMO

Food and feed safety risk assessment uses multi-parameter models to evaluate the likelihood of adverse events associated with exposure to hazards in human health, plant health, animal health, animal welfare, and the environment. Systematic review and meta-analysis are established methods for answering questions in health care, and can be implemented to minimize biases in food and feed safety risk assessment. However, no methodological frameworks exist for refining risk assessment multi-parameter models into questions suitable for systematic review, and use of meta-analysis to estimate all parameters required by a risk model may not be always feasible. This paper describes novel approaches for determining question suitability and for prioritizing questions for systematic review in this area. Risk assessment questions that aim to estimate a parameter are likely to be suitable for systematic review. Such questions can be structured by their "key elements" [e.g., for intervention questions, the population(s), intervention(s), comparator(s), and outcome(s)]. Prioritization of questions to be addressed by systematic review relies on the likely impact and related uncertainty of individual parameters in the risk model. This approach to planning and prioritizing systematic review seems to have useful implications for producing evidence-based food and feed safety risk assessment.


Assuntos
Meio Ambiente , Inocuidade dos Alimentos , Alimentos , Valor Nutritivo , Ração Animal/efeitos adversos , Bem-Estar do Animal/normas , Animais , Manipulação de Alimentos/métodos , Humanos , Plantas , Medição de Risco , Toxicologia
3.
Health Educ Res ; 29(4): 566-82, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24488650

RESUMO

This article discusses how process indicators can complement outcomes as part of a comprehensive explanatory evaluation framework, using the example of skills-based behavioural interventions to prevent sexually transmitted infections and promote sexual health among young people in schools. A systematic review was conducted, yielding 12 eligible outcome evaluations, 9 of which included a process evaluation. There were few statistically significant effects in terms of changes in sexual behaviour outcomes, but statistically significant effects were more common for knowledge and self-efficacy. Synthesis of the findings of the process evaluations identified a range of factors that might explain outcomes, and these were organized into two overarching categories: the implementation of interventions, and student engagement and intervention acceptability. Factors which supported implementation and engagement and acceptability included good quality teacher training, involvement and motivation of key school stakeholders and relevance and appeal to young people. Factors which had a negative impact included teachers' failure to comprehend the theoretical basis for behaviour change, school logistical problems and omission of topics that young people considered important. It is recommended that process indicators such as these be assessed in future evaluations of school-based sexual health behavioural interventions, as part of a logic model.


Assuntos
Avaliação de Processos e Resultados em Cuidados de Saúde , Saúde Reprodutiva , Infecções Sexualmente Transmissíveis/prevenção & controle , Adolescente , Comportamento do Adolescente , Educação em Saúde , Humanos , Comportamento Reprodutivo , Serviços de Saúde Escolar , Adulto Jovem
4.
Health Technol Assess ; 16(23): iii-xiii, 1-137, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22564553

RESUMO

BACKGROUND: The present report was commissioned as a supplement to an existing technology assessment report produced by the Peninsula Technology Assessment Group (PenTAG), which evaluated the clinical effectiveness and cost-effectiveness of dasatinib and nilotinib in patients who are either resistant or intolerant to standard-dose imatinib. OBJECTIVES: This report evaluates the clinical effectiveness and cost-effectiveness of dasatinib, nilotinib and high-dose imatinib within their licensed indications for the treatment of people with chronic myeloid leukaemia (CML) who are resistant to standard-dose imatinib. DATA SOURCES: Bibliographic databases were searched from inception to January 2011, including The Cochrane Library, MEDLINE (Ovid), EMBASE (Ovid), and MEDLINE In-Process & Other Non-Indexed Citations. Bibliographies of related papers were screened, key conferences were searched, and experts were contacted to identify additional published and unpublished references. REVIEW METHODS: This report includes systematic reviews of clinical effectiveness and cost-effectiveness studies, an independent appraisal of information submitted by drug manufacturers to the National Institute for Health and Clinical Excellence (NICE), an independent appraisal of the PenTAG economic evaluation, and new economic analyses adapting the PenTAG economic model. Standard systematic procedures involving two reviewers to maintain impartiality and transparency, and to minimise bias, were conducted. RESULTS: Eleven studies met the inclusion criteria. Four of these studies included new data published since the PenTAG report; all of these were in chronic-phase CML. No relevant studies on the clinical effectiveness of nilotinib were found. The clinical effectiveness studies on dasatinib [one arm of a randomised controlled trial (RCT)] and high-dose imatinib (one arm of a RCT and three single-arm cohort studies) had major methodological limitations. These limitations precluded a comparison of the different arms within the RCT. Data from the studies are summarised in this report, but caution in interpretation is required. One economic evaluation was identified that compared dasatinib with high-dose imatinib in patients with chronic-phase CML who were CML resistant to standard-dose imatinib. Two industry submissions and the PenTAG economic evaluation were critiqued and differences in the assumptions and results were identified. The PenTAG economic model was adapted and new analyses conducted for the interventions dasatinib, nilotinib and high-dose imatinib and the comparators interferon alfa, standard-dose imatinib, stem cell transplantation and hydroxycarbamide. The results suggest that the three interventions, dasatinib, nilotinib and high-dose imatinib, have similar costs and cost-effectiveness compared with hydroxycarbamide, with a cost-effectiveness of around £30,000 per quality-adjusted life-year gained. However, it is not possible to derive firm conclusions about the relative cost-effectiveness of the three interventions owing to great uncertainty around data inputs. Uncertainty was explored using deterministic sensitivity analyses, threshold analyses and probabilistic sensitivity analyses. LIMITATIONS: The paucity of good-quality evidence should be considered when interpreting this report. CONCLUSIONS: This review has identified very limited new information on clinical effectiveness of the interventions over that already shown in the PenTAG report. Limitations in the data exist; however, the results of single-arm studies suggest that the interventions can lead to improvements in haematological and cytogenetic responses in people with imatinib-resistant CML. The economic analyses do not highlight any one of the interventions as being the most cost-effective; however, the analysis results are highly uncertain owing to lack of agreement on appropriate assumptions. Recommendations for future research made by PenTAG, for a good-quality RCT comparing the three treatments remain.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Tiazóis/uso terapêutico , Antineoplásicos/economia , Benzamidas , Intervalos de Confiança , Análise Custo-Benefício , Dasatinibe , Progressão da Doença , Resistência a Medicamentos , Quimioterapia Combinada , Humanos , Mesilato de Imatinib , Estimativa de Kaplan-Meier , Leucemia Mielogênica Crônica BCR-ABL Positiva/economia , Modelos Econômicos , Piperazinas/economia , Inibidores de Proteínas Quinases/economia , Pirimidinas/economia , Anos de Vida Ajustados por Qualidade de Vida , Tiazóis/economia , Resultado do Tratamento , Reino Unido
5.
Health Technol Assess ; 15(2): 1-182, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21247515

RESUMO

OBJECTIVE: To assess the long-term clinical effectiveness and cost-effectiveness of multicomponent weight management schemes for adults in terms of weight loss and maintenance of weight loss. DATA SOURCES: Bibliographic databases were searched from inception to December 2009, including the Cochrane Library, MEDLINE (Ovid), EMBASE (Ovid), and MEDLINE In-Process & Other Non-Indexed Citations. Bibliographies of related papers were screened, key conferences and symposia were searched and experts were contacted to identify additional published and unpublished references. REVIEW METHODS: For the clinical effectiveness review, two reviewers independently screened titles and abstracts for eligibility. Inclusion criteria were applied to the full text of retrieved papers by one reviewer and checked by a second reviewer using a pre-piloted inclusion flow chart. The studies were long-term randomised controlled trials (RCTs) of adult participants who were classified by body mass index as overweight or obese. Interventions were multicomponent weight management programmes (including diet, physical activity and behaviour change strategies) that assessed weight measures. Programmes that involved the use of over-the-counter medicines licensed in the UK were also eligible. For the cost-effectiveness review two reviewers independently screened studies for inclusion. Cost-effectiveness, cost-utility, cost-benefit or cost-consequence analyses were eligible. Data were extracted using a standardised and pre-piloted data extraction form. The quality of included studies was assessed using standard criteria. Studies were synthesised through a narrative review with full tabulation of results. RESULTS: A total of 3358 references were identified, of which 12 were included in the clinical effectiveness review. Five RCTs compared multicomponent interventions with non-active comparator groups. In general, weight loss appeared to be greater in the intervention groups than in the comparator groups. Two RCTs compared multicomponent interventions that focused on the diet component. In these studies there were no statistically significant differences in weight loss between interventions. Four RCTs compared multicomponent interventions that focused on the physical activity component. There was little consistency in the pattern of results seen, in part owing to the differences in the interventions. In one RCT the intervention focused on the goal-setting interval and it appeared that weight loss was greatest in those given daily goals compared with weekly goals. Overall, where measured, it appeared that most groups began to regain weight at further follow-up. Of the 419 studies identified in the cost-effectiveness searches, none met the full inclusion criteria. Two economic evaluations are described in our review; however, caution is required in their interpretation, as they did not meet all inclusion criteria. Lifetime chronic disease models were used in these studies and the models included the costs and benefits of avoiding chronic illness. Both studies found the interventions to be cost-effective, with estimates varying between -£473 and £7200 (US$12,640) per quality-adjusted life-year gained; methodological omissions from these studies were apparent and caution is therefore required in the interpretation of these results. CONCLUSIONS: Long-term multicomponent weight management interventions were generally shown to promote weight loss in overweight or obese adults. Weight changes were small however and weight regain was common. There were few similarities between the included studies; consequently an overall interpretation of the results was difficult to make. There is some evidence that weight management interventions are likely to be cost-effective, although caution is required as there were some limitations in the two cost-evaluation studies described. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Assuntos
Obesidade/terapia , Resultado do Tratamento , Adolescente , Adulto , Idoso , Terapia Comportamental , Análise Custo-Benefício , Dieta Redutora , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Reino Unido , Adulto Jovem
6.
Health Technol Assess ; 14(42): 1-209, iii-iv, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20849734

RESUMO

BACKGROUND: Recombinant human growth hormone (rhGH) is licensed for short stature associated with growth hormone deficiency (GHD), Turner syndrome (TS), Prader-Willi syndrome (PWS), chronic renal insufficiency (CRI), short stature homeobox-containing gene deficiency (SHOX-D) and being born small for gestational age (SGA). OBJECTIVES: To assess the clinical effectiveness and cost-effectiveness of rhGH compared with treatment strategies without rhGH for children with GHD, TS, PWS, CRI, SHOX-D and those born SGA. DATA SOURCES: The systematic review used a priori methods. Key databases were searched (e.g. MEDLINE, EMBASE, NHS Economic Evaluation Database and eight others) for relevant studies from their inception to June 2009. A decision-analytical model was developed to determine cost-effectiveness in the UK. STUDY SELECTION: Two reviewers assessed titles and abstracts of studies identified by the search strategy, obtained the full text of relevant papers, and screened them against inclusion criteria. STUDY APPRAISAL: Data from included studies were extracted by one reviewer and checked by a second. Quality of included studies was assessed using standard criteria, applied by one reviewer and checked by a second. Clinical effectiveness studies were synthesised through a narrative review. RESULTS: Twenty-eight randomised controlled trials (RCTs) in 34 publications were included in the systematic review. GHD: Children in the rhGH group grew 2.7 cm/year faster than untreated children and had a statistically significantly higher height standard deviation score (HtSDS) after 1 year: -2.3 ± 0.45 versus -2.8 ± 0.45. TS: In one study, treated girls grew 9.3 cm more than untreated girls. In a study of younger children, the difference was 7.6 cm after 2 years. HtSDS values were statistically significantly higher in treated girls. PWS: Infants receiving rhGH for 1 year grew significantly taller (6.2 cm more) than those untreated. Two studies reported a statistically significant difference in HtSDS in favour of rhGH. CRI: rhGH-treated children in a 1-year study grew an average of 3.6 cm more than untreated children. HtSDS was statistically significantly higher in treated children in two studies. SGA: Criteria were amended to include children of 3+ years with no catch-up growth, with no reference to mid-parental height. Only one of the RCTs used the licensed dose; the others used higher doses. Adult height (AH) was approximately 4 cm higher in rhGH-treated patients in the one study to report this outcome, and AH-gain SDS was also statistically significantly higher in this group. Mean HtSDS was higher in treated than untreated patients in four other studies (significant in two). SHOX-D: After 2 years' treatment, children were approximately 6 cm taller than the control group and HtSDS was statistically significantly higher in treated children. The incremental cost per quality adjusted life-year (QALY) estimates of rhGH compared with no treatment were: 23,196 pounds for GHD, 39,460 pounds for TS, 135,311 pounds for PWS, 39,273 pounds for CRI, 33,079 pounds for SGA and 40,531 pounds for SHOX-D. The probability of treatment of each of the conditions being cost-effective at 30,000 pounds was: 95% for GHD, 19% for TS, 1% for PWS, 16% for CRI, 38% for SGA and 15% for SHOX-D. LIMITATIONS: Generally poorly reported studies, some of short duration. CONCLUSIONS: Statistically significantly larger HtSDS values were reported for rhGH-treated children with GHD, TS, PWS, CRI, SGA and SHOX-D. rhGH-treated children with PWS also showed statistically significant improvements in body composition measures. Only treatment of GHD would be considered cost-effective at a willingness-to-pay threshold of 20,000 to 30,000 pounds per QALY gained. This analysis suggests future research should include studies of longer than 2 years reporting near-final height or final adult height.


Assuntos
Nanismo Hipofisário/tratamento farmacológico , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Biomarcadores , Composição Corporal , Análise Custo-Benefício , Nanismo Hipofisário/economia , Transtornos do Crescimento/economia , Hormônio do Crescimento Humano/economia , Humanos , Incidência , Modelos Lineares , Modelos Econômicos , Prevalência , Prognóstico , Garantia da Qualidade dos Cuidados de Saúde , Qualidade de Vida/psicologia , Anos de Vida Ajustados por Qualidade de Vida , Estados Unidos
7.
Health Technol Assess ; 14(7): 1-206, iii-iv, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20178696

RESUMO

OBJECTIVES: To assess the effectiveness and cost-effectiveness of schools-based skills-building behavioural interventions to encourage young people to adopt and maintain safer sexual behaviour and to prevent them from acquiring sexually transmitted infections (STIs). DATA SOURCES: Electronic bibliographic databases (e.g. MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, CINAHL, PsycINFO, CCRCT, NHS EED and DARE) were searched for the period 1985 to March 2008. Bibliographies of systematic reviews and related papers were screened and experts contacted to identify additional published and unpublished references. REVIEW METHODS: A systematic review of effectiveness and economic evaluation of cost-effectiveness were carried out. A descriptive map of studies that met inclusion criteria was produced, and keywords were developed and systematically applied to these studies to identify a policy-relevant subset of studies for the systematic review. Outcome data for variables including sexual behaviour were extracted. An economic model was developed to compare the costs and consequences of the behavioural interventions. A Bernoulli statistical model was constructed to describe the probability of STI infection. RESULTS: There were few significant differences between the interventions and comparators in terms of changes in sexual behaviour outcomes, although there were some significant differences for knowledge and some measures of self-efficacy. The studies included in this review conducted relatively short follow-up assessments at a time when many young people were becoming sexually active. It is therefore possible that favourable behaviour change may have occurred, and become more cost-effective, with time, as sexual activity becomes more routine in young people's lives. The quality of the intervention provider influenced whether or not young people found the interventions to be acceptable and engaging; enthusiasm and considerable expertise were important for effective class management and delivery of skills-building activities, and a supportive school culture was also helpful. Recognition of young people's individual needs in relation to sexual health was another important factor. No conclusions could be drawn on the impact of the interventions on sexual health inequalities due to a lack of relevant data on socioeconomic status, gender and ethnicity. The results of the economic evaluation were considered to be illustrative, mainly due to the uncertainty of the effect of intervention on behavioural outcomes. The results were most sensitive to changes in parameter values for the intervention effect, the transmission probability of STIs and the number of sexual partners. The costs of teacher-led and peer-led behavioural interventions, based on the resources estimated from the relevant randomised controlled trials in our systematic review, were 4.30 pounds and 15 pounds per pupil, respectively. Teacher-led interventions were more cost-effective than peer-led interventions due to the less frequent need for training. The incremental cost-effectiveness of the teacher-led and peer-led interventions was 20,223 pounds and 80,782 pounds per quality-adjusted life-year gained, respectively. An analysis of individual parameters revealed that future research funding should focus on assessing the intervention effect for condom use from a school-based intervention. CONCLUSIONS: School-based behavioural interventions for the prevention of STIs in young people can bring about improvements in knowledge and increased self-efficacy, but the interventions did not significantly influence sexual risk-taking behaviour or infection rates. Future investigation should include long-term follow-up to assess the extent to which safer sexual behaviour is adopted and maintained into adulthood, and prospective cohort studies are needed to look at the parameters that describe the transmission of STIs between partners. Funding should focus on the effectiveness of the interventions on influencing behaviour.


Assuntos
Comportamento do Adolescente , Comportamento de Redução do Risco , Infecções Sexualmente Transmissíveis/prevenção & controle , Adolescente , Análise Custo-Benefício , Feminino , Humanos , Masculino , Sexo Seguro , Instituições Acadêmicas , Educação Sexual , Reino Unido , Adulto Jovem
8.
Health Technol Assess ; 12(28): iii-iv, ix-95, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18547499

RESUMO

OBJECTIVES: To assess the clinical and cost-effectiveness of magnesium sulphate compared with sotalol, and to assess the clinical effectiveness of magnesium sulphate compared with placebo in the prevention of atrial fibrillation (AF) in patients who have had a coronary artery bypass graft (CABG). DATA SOURCES: Major electronic databases were searched from December 2003 to May 2007. REVIEW METHODS: Selected studies were assessed, subjected to data extraction using a standard template and quality assessment using published criteria. A simple short-term economic model was developed, informed by a systematic review of economic evaluations and populated with data from a review of costing/resource-use studies and other published studies. The cost-effectiveness of magnesium sulphate as prophylaxis was estimated for a set of base-case assumptions and the robustness of these results was assessed using deterministic and probabilistic sensitivity analysis. RESULTS: Twenty-two papers met the inclusion criteria reporting 15 trials which all compared magnesium sulphate with placebo or control. They ranged in size from 15 to 176 patients randomised, and were conducted in Europe, the USA and Canada. The standard of reporting was generally poor, with details of key methodological attributes difficult to elucidate. No trials were identified that specifically aimed to compare magnesium sulphate with sotalol. Of 1070 patients in the pooled magnesium group, 230 (21%) developed postoperative AF, compared with 307 of 1031 (30%) patients in the placebo or (control) group. Meta-analysis using a fixed-effects model generated a pooled odds ratio (OR) that was significantly less than 1.0 [OR=0.65, 95% confidence interval (CI) 0.53 to 0.79, test for overall effect p<0.0001], but with statistically significant heterogeneity (I2=63.4%, p=0.0005). Two randomised controlled trials (RCTs) were notable as they had relatively lower ORs in favour of magnesium sulphate. When these were removed from the analyses the pooled OR remained statistically significant, but heterogeneity no longer remained significant. These two studies tended to impart a highly significant reduction in the odds of AF to whichever subgroup they were analysed in. When studies were ordered by total duration of prophylaxis, an apparent relationship between duration and odds of AF was evident, with decreasing odds of AF as duration of prophylaxis increased. This was confirmed by linear regression analysis (R2=0.743, p<0.001). When the data were grouped into three classes according to duration, a statistically significant intervention effect was only present for the longest duration (OR=0.12, 95% CI 0.06 to 0.23, p=0.00001). Statistically significant intervention effects were associated with the initiation of prophylaxis 12 hours or more before surgery (OR 0.26; 95% CI 0.16 to 0.44, test for overall effect p=0.00001, fixed-effects model) and less than 12 hours before surgery or during the surgery itself (OR=0.73, 95% CI 0.56 to 0.97, test for overall effect p = 0.03, fixed-effects model), but not when prophylaxis was initiated at the end of surgery or postsurgery (OR=0.85, 95% CI 0.59 to 1.22, p=0.37, fixed-effects model). When studies were ordered by total dose of intravenous magnesium sulphate (<25 g), the odds of AF were independent of the dose. A notable exception was that for a total dose of 9 g magnesium sulphate; here the odds of AF were significantly reduced relative to the control group, although this may be explained by the fact that these studies had excluded patients who were on antiarrhythmic drugs and so may have been at higher risk of AF. Sixty-three potentially relevant references about cost-effectiveness were identified, but no economic evaluations of intravenous magnesium alone as prophylaxis against AF following CABG, compared with sotalol as prophylaxis or no prophylaxis, were identified. Studies reporting resource use by patients with AF following CABG suggest that while AF significantly increased inpatient stays, by up to 2.3 days in the intensive care unit (ICU) and 3.4 days on the ward, differences in length of stay and costs between patients receiving prophylaxis and those not receiving prophylaxis were not statistically significant. In the base-case analysis, magnesium sulphate prophylaxis resulted in 0.081 fewer cases of AF at an incremental cost of 2.55 pounds sterling. The incremental cost-effectiveness ratio (ICER) was 32 pounds sterling per AF case avoided. The estimated difference in average length of stay between the prophylaxis and no-prophylaxis strategies was only 0.24 days, despite a large assumed difference of 3 days for patients experiencing AF in each group (1 extra day in the ICU and 2 extra days on the ward). In a deterministic sensitivity analysis the greatest variation in ICERs was observed for input parameters relating to the baseline risk of AF following CABG and the effectiveness of prophylaxis, cost of prophylaxis and the resource consequences of postoperative AF. The largest ICER (2092 pounds sterling) in the sensitivity analysis was associated with increasing the length of patients' preoperative stay. In the base case it was assumed that admission routines would be identical under both strategies. However, patients receiving prophylaxis by intravenous infusion may have longer preoperative stays. In a probabilistic analysis the majority of the simulations were associated with improved outcomes (in this case fewer cases of AF), but also higher costs. Prophylaxis was the dominant strategy (better outcome at lower cost) in about 41% of the simulations using the base-case assumptions. Under an alternative scenario where patients receiving prophylaxis are admitted for longer before their operation, to receive their initial infusion, the proportion of simulations where prophylaxis dominates fell to around 5%. The probability of being cost-effective was 99% at a willingness to pay (WTP) threshold of 2000 pounds sterling per AF case avoided and 100% at a WTP threshold of 5000 pounds sterling per AF case avoided under the base-case assumptions. Under the alternative scenario of longer preoperative stays the probability of being cost-effective at these two threshold values fell to 48% and 93%, respectively. It is unclear what the appropriate decision threshold should be, given that this model used intermediate rather than final outcomes. CONCLUSIONS: No RCTs were identified that specifically aimed to compare intravenous magnesium with sotalol as prophylaxis for AF in patients undergoing CABG. Intravenous magnesium, compared with placebo or control, is effective in preventing postoperative AF, as confirmed by a statistically significant intervention effect based on pooled analysis of 15 RCTs. It was also found that AF was less likely to occur when a longer duration of prophylaxis was used, and the earlier that prophylaxis is started; however, this finding was associated with two RCTs that had more favourable results than the other trials. No clear relationship between dose and AF was observed, although a lower constant dose rate was associated with the lowest odds of AF. Further research should investigate the relationship between dose, dose rate, duration of prophylaxis, timing of initiation of therapy and patient characteristics, such as degree of risk for AF. This will provide stronger evidence for the optimum delivery of intravenous magnesium in patients undergoing CABG. In the base-case analysis in the economic model, magnesium sulphate prophylaxis reduced the number of postoperative AF cases at a modest increase in cost. The results of the economic analysis are highly sensitive to variation in certain key parameters. Prophylaxis is less likely to be a cost-effective option if it requires changes in admission routines that result in longer preoperative stays than would be the case without prophylaxis.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/prevenção & controle , Ponte de Artéria Coronária , Análise Custo-Benefício , Sulfato de Magnésio/uso terapêutico , Sotalol/uso terapêutico , Antiarrítmicos/administração & dosagem , Antiarrítmicos/economia , Bases de Dados Factuais , Humanos , Infusões Intravenosas , Sulfato de Magnésio/administração & dosagem , Sulfato de Magnésio/economia , Ensaios Clínicos Controlados Aleatórios como Assunto , Sotalol/administração & dosagem , Sotalol/economia
9.
Health Technol Assess ; 12(19): iii-iv, 1-360, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18485271

RESUMO

OBJECTIVES: To assess the clinical and cost-effectiveness of inhaled corticosteroids (ICS) alone and ICS used in combination with a long-acting beta2 agonist (LABA) in the treatment of chronic asthma in adults and children aged over 12 years. DATA SOURCES: Major electronic bibliographic databases, e.g. MEDLINE and EMBASE, were searched up to February/March 2006 (and updated again in October 2006). REVIEW METHODS: A systematic review of clinical and cost-effectiveness studies was conducted. Cost comparison and cost-consequence analyses were performed where appropriate. RESULTS: The assessment of clinical effectiveness was based on the 67 randomised controlled trials selected from the 5175 reports identified through the systematic literature search. The most frequently reported relevant outcomes were lung function, symptoms, use of rescue medication and adverse events. The trials varied considerably. In the trials that compared low-dose ICS versus ICS and high-dose ICS versus ICS, there were few significant differences in clinical effectiveness, although a few of the trials had assessed non-inferiority between the comparators rather than superiority. At doses of 400, 800 and 'high-level' doses of 1500 or 1600 microg/day, beclometasone dipropionate (BDP) appears to be the current cheapest ICS product both with the inclusion and exclusion of chlorofluorocarbon (CFC)-propelled products. A significant treatment benefit for combination ICS/LABA therapy across a range of outcomes compared with ICS alone was identified [when the ICS was double the accepted clinically equivalent dose of the ICS in the combination inhaler, and dry powder inhalers (DPIS) were used to deliver the drugs]. When a formoterol fumarate (FF)/salmeterol (SAL) combination inhaler and a budesonide (BUD)/FF combination inhaler were each compared with their constituent drugs delivered in separate inhalers, there were very few statistically significant differences between the treatments across the various efficacy outcomes and the rate of adverse events. Combination inhalers were more often cheaper than doubling the dose of ICS alone. However, the costs were highly variable and dependent on both the dose required and the preparation used in the trials. The estimated mean annual cost of FP/SAL combination varied from being 94 pounds cheaper to 109 pounds more expensive than the alternative of BUD at a higher dose. The BUD/FF combination varied from being 163 pounds cheaper to 66 pounds more expensive than the higher dose of either BUD or FP. When the combination inhalers were compared to each other, the results were mixed, with the FP/SAL combination significantly superior on some outcomes and the BUD/FF combination superior on others; however, meta-analysis showed that there were no significant differences between the two treatments in the rate of adverse events. Taking an ICS with a LABA as either of the two currently available combination products, FP/SAL and BUD/FF, is usually cheaper than taking the relevant constituent drugs in separate inhalers. At very high doses of BUD (1600 microg/day), however, the BUD/FF combination inhaler can be up to 156 pounds more expensive than having the same drugs in separate inhalers. In terms of the relative costs associated with taking one of the combination inhalers, at low dose (400 microg BUD or 200 microg FP/day) the cheapest combination inhaler is FP/SAL as a pressurised metered dose inhaler (pMDI) (Seretide Evohaler). However, this is only slightly cheaper than using BUD/FF as a DPI (Symbicort Turbohaler). At higher dose levels (800 microg BUD or 500 microg FP/day) FP/SAL as either pMDI aerosol (Seretide Evohaler) or a DPI (Seretide Accuhaler) is the cheapest combination product available, but again only slightly cheaper than the DPI BUD/FF combination (Symbicort Turbohaler). It should be highlighted, however, that the three head-to-head trials that compared the effects of FP/SAL with BUD/FF used the FP/SAL DPI combination inhaler, Seretide Accuhaler. CONCLUSIONS: The evidence indicates that there are few consistent significant differences in effects between the five ICS licensed for use in adults and adolescents over the age of 12 years, at either low or high dose. On average, BDP products currently tend to be the cheapest ICS available and tend to remain so as the daily ICS dose required increases. There is evidence that the addition of a LABA to an ICS is potentially more clinically effective than doubling the dose of ICS alone, although consistent significant differences between the two treatment strategies are not observed for all outcome measures. The cost differences between combination therapy compared with ICS monotherapy are highly variable and dependent on the dose required and the particular preparations used. For the combination therapies of ICS/LABA there are potential cost savings with the use of combination inhalers compared with separate inhalers, with few differences between the two treatment strategies in terms of effects. The only exception to this cost saving is with BUD/FF at doses higher than 1200 microg/day, where separate inhaler devices can become equivalent to or cheaper than combination inhalers. Neither of the two combination inhalers (FP/SAL or BUD/FF) is consistently superior in terms of treatment effect. A comparison of the costs associated with each combination therapy indicates that at low dose FP/SAL delivered via a pMDI is currently the cheapest combination inhaler but only marginally cheaper than BUD/FF delivered as a DPI. At higher doses, both the FP/SAL combination inhalers (PMDI and DPI) are marginally cheaper than BUD/FF (DPI). Future trials of treatment for chronic asthma should standardise the way in which outcome measures are defined and measured, with a greater focus on patient-centred outcomes. For informing future cost-utility and cost-effectiveness analyses from a UK NHS perspective, there is a need for longitudinal studies that comprehensively track the care pathways followed when people experience asthma exacerbations of different severity. Further research synthesis, quantifying the adverse effects of the different ICS, is required for treatment choices by patients and clinicians to be fully informed.


Assuntos
Corticosteroides/uso terapêutico , Agonistas Adrenérgicos beta/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Administração por Inalação , Adolescente , Corticosteroides/administração & dosagem , Corticosteroides/economia , Agonistas Adrenérgicos beta/administração & dosagem , Agonistas Adrenérgicos beta/economia , Adulto , Antiasmáticos/administração & dosagem , Antiasmáticos/economia , Doença Crônica , Análise Custo-Benefício , Quimioterapia Combinada , Humanos , Nebulizadores e Vaporizadores , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Health Technol Assess ; 12(20): 1-174, iii-iv, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18485272

RESUMO

OBJECTIVES: To assess the clinical and cost-effectiveness of inhaled corticosteroids (ICS) alone and ICS used in combination with a long-acting beta2 agonist (LABA) in the treatment of chronic asthma in children aged under 12 years. DATA SOURCES: Major electronic bibliographic databases, e.g. MEDLINE and EMBASE, were searched up to February/March 2006 (and updated again in October 2006). REVIEW METHODS: A systematic review of clinical and cost-effectiveness studies and economic analyses were carried out. A flexible framework was used to allow different types of economic analyses as appropriate, with either a cost comparison or cost-consequence comparison conducted. RESULTS: Of 5175 records identified through systematic literature searching, 34 records describing 25 studies were included (16 were fully published randomised controlled trials, six were systematic reviews, and three were post-2004 conference abstracts). The most frequently reported relevant outcomes in the 16 RCTs were peak expiratory flow rate (13 trials), FEV1 (13 trials), symptoms (13 trials), adverse events or exacerbations (13 trials), use of rescue medication (12 trials), markers of adrenal function (e.g. blood or urine cortisol concentrations) (13 trials), height and/or growth rate (seven trials) and markers of bone metabolism (two trials). In the trials that compared low-dose ICS versus ICS and high-dose ICS versus ICS, no consistent significant differences or patterns in differential treatment effect among the outcomes were evident. Where differences were statistically significant at high doses, such as for lung function and growth, they favoured formoterol fumarate (FF), but this was generally in studies that did not compare the ICS at the accepted clinically equivalent doses. Differences between the drugs in impact on adrenal suppression were only significant in two studies. At doses of 200, 400 and 800 microg/day, beclometasone dipropionate (BDP) appears to be the current cheapest ICS product both with the inclusion and exclusion of chlorofluorocarbon (CFC)-propelled products. In the trials comparing ICS at a higher dose with ICS and LABA in combination, most outcomes favoured the combined inhaler. Only the combination inhaler, Seretide Evohaler, is slightly cheaper than the weighted mean cost of all types of ICS at increased dose except BDP 400 microg/day (including CFC-propelled products). Both the combination inhalers, Seretide Accuhaler and Symbicort Turbohaler, are more expensive than the weighted mean cost for all types of ICS at a two-fold increased dose. Compared with the lowest cost preparation for each ICS drug, all the combination inhalers are always more expensive than the ICS products at increased dose. CONCLUSIONS: The limited evidence available indicates that there are no consistent significant differences in effectiveness between the three ICS licensed for use in children at either low or high dose. BDP CFC-propelled products are often the cheapest ICS currently available at both low and high dose, and may remain so even when CFC-propelled products are excluded. Exclusion of CFC-propelled products increases the mean annual cost of all budesonide (BUD) and BDP, while the overall cost differences between the comparators diminish. There is very limited evidence available for the efficacy and safety of ICS and LABAs in children. From this limited evidence, there appear to be no significant clinical differences in effects between the use of a combination inhaler versus the same drugs in separate inhalers. There is a lack of evidence comparing ICS at a higher dose with ICS and LABA in combination and comparing the combination products with each other. In the absence of any evidence concerning the effectiveness of ICS at higher dose with ICS and LABA, a cost-consequence analysis gives mixed results. There are potential cost savings with the use of combination inhalers compared to separate inhalers. At present prices, the BUD/FF combination is more expensive than those containing FP/SAL, but it is not known whether there are clinically significant differences between them. A scoping review is required to assess the requirements for additional primary research on the clinical effectiveness of treatment for asthma in children under 5 years old. Such a review could also usefully include all treatment options, pharmacological and non-pharmacological, for asthma. A direct head-to-head trial that compares the two combination therapies of FP/SAL and BUD/FF is warranted, and it is important to assess whether the addition of a LABA to a lower dose of ICS could potentially be as effective as an increased dose of ICS alone, but also be steroid sparing. There is also a need for the long-term adverse events associated with ICS use to be assessed systematically. Future trials of treatment for chronic asthma in children should aim to standardise further the way in which outcome measures are defined. There should be a greater focus on patient-centred outcomes to provide a more meaningful estimation of the impact of treatment on asthma control. Methods of reporting also require standardisation.


Assuntos
Corticosteroides/uso terapêutico , Agonistas Adrenérgicos beta/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Administração por Inalação , Corticosteroides/administração & dosagem , Corticosteroides/economia , Agonistas Adrenérgicos beta/administração & dosagem , Agonistas Adrenérgicos beta/economia , Antiasmáticos/administração & dosagem , Antiasmáticos/economia , Criança , Pré-Escolar , Doença Crônica , Análise Custo-Benefício , Humanos , Lactente , Recém-Nascido , Nebulizadores e Vaporizadores , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Health Technol Assess ; 12(9): 1-116, iii, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18405469

RESUMO

OBJECTIVE: To examine the clinical effectiveness of patient education models for adults with Type 2 diabetes. DATA SOURCES: Electronic databases were searched from 2002 to January 2007. REVIEW METHODS: A systematic review of the literature on educational interventions in diabetes was undertaken. This was an update of a previous systematic review. RESULTS: Including studies identified in the previous systematic review, there were 13 published studies. Eight studies of education on multiple aspects of diabetes self-management were identified that provided education that was focused on a particular aspect of self-management. The quality of reporting and methodology of the studies was variable. Studies of multi-component educational interventions yielded mixed results. Some trials reported significant improvements on measures of diabetic control but others did not. Positive effects may be attributable to longer-term interventions with a shorter duration between the end of the intervention and the follow-up evaluation point. There may also be an effect of having a multi-professional team delivering the educational programme. Studies of focused educational interventions did not yield consistent results. Some effects were shown on measures of diabetic control in studies that focused on diet or exercise alone. Although the effects shown were generally small, those that were present did appear to be relatively long-lasting. This update review does not substantially alter the conclusions of the previous systematic review; for each outcome, the proportion of studies that demonstrated significant effects of education was similar. CONCLUSIONS: Based on the evidence, it would seem that education delivered by a team of educators, with some degree of reinforcement of that education made at additional points of contact, may provide the best opportunity for improvements in patient outcomes. Educators need to have time and resources to fulfil the needs of any structured educational programme. There is also a need for education to have a clear programme at the outset. From the evidence reported it is unclear what resources would need to be directed at the educators themselves to ensure that they can deliver programmes successfully. Any future research should consider patient education within the context of overall diabetes care and as such follow guidelines for the development and evaluation of complex interventions. Good-quality, longer-term studies would be desirable, but these would require careful consideration around the nature of any control group. Information is needed to clarify the sensitivity of diabetes education programmes to the performance of the diabetes educators, in order to ensure success and cost-effectiveness of education programmes.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Educação de Pacientes como Assunto , Glicemia/análise , Pressão Sanguínea , Índice de Massa Corporal , Ensaios Clínicos como Assunto , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas/análise , Humanos , Incidência , Lipídeos/sangue , Prevalência , Reforço Psicológico , Autocuidado/métodos , Autocuidado/estatística & dados numéricos , Avaliação da Tecnologia Biomédica , Resultado do Tratamento
13.
Anal Bioanal Chem ; 387(4): 1259-68, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17186225

RESUMO

The presence of human and veterinary pharmaceuticals in the environment has caused increasing concern due their effects on ecological receptors. Improving the risk assessment of these compounds necessitates a quantitative understanding of their metabolism and elimination in the target organism (toxicokinetics), particularly via the ubiquitous cytochrome P-450 (CYP) system and their mechanisms of toxicity (toxicodynamics). This review focuses on a number of pharmaceuticals and veterinary medicines of environmental concern, and the differences and similarities between ecological and human risk assessment. CYP metabolism is discussed with particular reference to its ubiquity in species of ecological relevance. The important issue of pharmaceutical mixtures is discussed to assess how emerging technologies such as ecotoxicogenomics may assist in moving towards a more mechanism-based environmental risk assessment of pharmaceuticals.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Meio Ambiente , Preparações Farmacêuticas/análise , Toxicologia , Animais , Citocromos/metabolismo , Ecologia , Humanos , Preparações Farmacêuticas/química , Medição de Risco
14.
Ecotoxicol Environ Saf ; 46(1): 64-72, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10805995

RESUMO

Foliar sprays of the systemic fungicides carbendazim, propiconazole, and triadimenol were applied in summer to replicated barrier-enclosed and open plots in a field of winter wheat in southern England at dose rates equivalent to label recommendations. Surface-active Collembola (springtails) were sampled from the experimental plots by suction sampling and pitfall trapping before and after the fungicide applications. No consistent effects of the fungicides on collembolan activity were detected using pitfall trapping but suction sampling revealed a transient negative effect of propiconazole and triadimenol on the overall abundance of higher collembolan taxa. Among individual species, however, fungicide effects varied spatially. Fewer significant treatment effects were obtained in enclosed than in open plots and no consistent effects of carbendazim were detected. The relevance of these findings to current fungicide usage strategies in British arable crops, which include the use of complex tank mixes, is discussed.


Assuntos
Artrópodes/efeitos dos fármacos , Benzimidazóis/toxicidade , Carbamatos , Fungicidas Industriais/toxicidade , Triazóis/toxicidade , Triticum/microbiologia , Animais
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