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ABSTRACT: OBJECTIVE: Identification of the fetus at risk of compromise is crucial to judicious allocation of monitoring resources and use of preventative treatment with the prospect of improving perinatal outcome. The accuracy of middle cerebral artery (MCA) Doppler for prediction of the fetus at risk of compromise of wellbeing is not known. The objective of this systematic review with bivariate meta-analysis was to evaluate the accuracy of middle cerebral artery Doppler for prediction of compromise of fetal/neonatal wellbeing. STUDY DESIGN: Systematic review and bivariate meta-analysis with searches of Medline, Embase, Cochrane library, Medion (inception to October 2011), hand searching of journal and reference lists, contact with experts. Two reviewers independently selected articles in which the results of middle cerebral artery Doppler were associated with the occurrence of compromise of fetal/neonatal wellbeing. There were no language restrictions applied. RESULTS: Thirty-five studies, testing 4025 fetuses, met the selection criteria. Data were extracted on study characteristics, quality and results to construct 2×2 tables. Likelihood ratios for positive and negative test results, sensitivity, specificity and their 95% confidence intervals were generated for the different indices and thresholds. Meta-analysis showed low predictive accuracy. For prediction of adverse perinatal outcome and perinatal mortality the results were positive likelihood ratios 2.77 (1.93, 3.96) and 1.36 (1.10, 1.67) and negative likelihood ratios 0.58 (0.48, 0.69) and 0.51 (0.29, 0.89) respectively. CONCLUSION: Abnormal middle cerebral artery Doppler showed limited predictive accuracy for compromise of fetal/neonatal wellbeing. High quality primary research or individual patient data meta-analysis looking at this test in combination with other tests is required.
European journal of obstetrics, gynecology, and reproductive biology 08/2012; · 1.97 Impact Factor
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ABSTRACT: For chronic pain treatment many health care authorities consider morphine to be the reference standard for strategic decisions in pain therapy. Although morphine's effectiveness is clear and its cost is low, it's unclear whether morphine should remain the first choice or reference treatment.
We performed a systematic review to evaluate the evidence available to support the position of morphine as the reference standard for step III opioids based on efficacy and tolerability outcomes.
The search yielded 5,675 titles and 56 studies were included. Considerable heterogeneity precluded pair-wise meta-analysis on change of pain intensity and no difference between morphine and other opioids were found for tolerability outcomes. The network meta-analysis showed no statistically significant difference in change of pain intensity between morphine and oxycodone, methadone and oxymorphone. Compared to morphine, patients using buprenorphine are more likely to discontinue treatment due to lack of effect (OR 2.32, 95% CI 1.37 to 3.95). Patients using methadone are more likely to discontinue due to adverse events (OR 3.09, 95% CI 1.14 to 8.36), whereas this risk is decreased for patients using fentanyl (OR 0.29, 95% CI 0.17 to 0.50) or buprenorphine (OR 0.30, 95% CI 0.16 to 0.53). The most important limitation of this review is that the included studies are heterogeneous with regard to study population and intervention, which may affect the pooled effect estimates. The main strength is that we only included parallel RCTs, the strongest design for intervention studies.
The current evidence is moderate, both in respect to the number of directly comparative studies and in the quality of reporting of these studies. No clear superiority in efficacy and tolerability of morphine over other opioids was found in pair-wise and network analyses. Based on these results, a justification for the placement of morphine as the reference standard for the treatment of severe chronic pain cannot be supported.
Current Medical Research and Opinion 07/2011; 27(7):1477-91. · 2.38 Impact Factor
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ABSTRACT: Chronic pain is common; however, good epidemiological data are scarce. Such information can help all the involved stakeholders to make responsible decisions about health budgets and prioritisation. This study aims to provide best-evidence epidemiological information about chronic pain in the Netherlands.
We performed a systematic search which yielded 16,619 references, 119 Dutch studies were relevant. We selected at least three studies per question that provided the most recent, representative and valid data.
The prevalence of moderate to severe general chronic pain among Dutch adults was estimated at 18%. This prevalence was 27% and 55% for any cancer pain. Up to 74% of patients with general or non-cancer chronic pain get treated; this percentage is little higher for patients with cancer pain. A substantial proportion of the patients receive drug treatment for their pain, mainly NSAIDs, but also non-pharmacological interventions for pain are being used. Up to 43% of the chronic non-cancer pain patients report not receiving treatment and up to 79% of the patients believe their pain is inadequately treated. All studies reported a detrimental effect of chronic pain on quality of life, activities of daily living and mental health. Chronic pain is also associated with direct and indirect medical costs, and patients may have decreased income and additional out-of pocket expenses.
Chronic pain occur s frequently, has a negative impact on the patient and society and treatment may not always be adequate. Chronic pain should be seen as an important public health problem deserving more attention of Dutch healthcare workers and policy makers.
The Netherlands Journal of Medicine 03/2011; 69(3):141-53. · 2.07 Impact Factor
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ABSTRACT: Several pharmacological treatments are used to manage post-herpetic neuralgia (PHN). The use of topical analgesics, such as 5% lidocaine-medicated plaster (5% LMP), may be preferable to systemic treatments in that they are formulated to produce a local pain relieving effect with minimal systemic absorption. However, direct head-to-head comparisons are relatively few, and a rigorous assessment of the relative efficacy and safety of the various treatment options is lacking. The objective of this study was to compare 5% LMP for the relief of PHN with other relevant interventions and placebo. Six databases were searched up to May 2010. Quantitative methods for data synthesis were used, and a network meta-analysis was conducted. Twenty unique studies (32 publications) were included. Placebo-controlled studies showed 5% LMP to be effective in providing pain relief and reducing allodynia while adverse event rates were generally low. A comparison between 5% LMP and pregabalin indicated the non-inferiority of 5% LMP for pain reduction and showed greater improvement of quality of life for 5% LMP. Adverse events (AE) were significantly fewer with 5% LMP. In the network meta-analysis, only 5% LMP and gabapentin were associated with a greater change in pain from baseline than placebo [-15.50 (95% CI -18.85 to -12.16) and -7.56 (95% CI -12.52 to -2.59) respectively]. 5% LMP was shown to be more effective than capsaicin [-16.45 (95% CI -20.04 to -12.86)], gabapentin [-7.95 (95% CI -13.29 to -2.61)] and pregabalin [-13.45 (95% CI -19.19 to -7.71)]. For pain relief, two comparators were more effective than placebo [mean pain relief, gabapentin: 32.77 (95% CI 15.57-49.97); 5% LMP: 26.77 (95% CI 9.11-44.43)]. 5% LMP was shown to be comparable to gabapentin [-6.00 (95% CI -25.32-13.32)]. The results suggest that 5% LMP and gabapentin have similar effects on pain relief and that 5% LMP is more effective than capsaicin and pregabalin (change in pain from baseline). Topical agents, such as 5% LMP, are associated with fewer and less clinically significant AE than is the case for systemic agents. However, small numbers, and limited size and quality of included studies should be taken into account. Further studies are needed.
Acta Neurologica Scandinavica 10/2010; 123(5):295-309. · 2.47 Impact Factor
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ABSTRACT: To determine the accuracy with which various types of tests for bacterial vaginosis (BV) predict spontaneous preterm birth in pregnant women, studies were identified, without language restrictions, through nine different databases and manual searching of bibliographies of known primary and review articles. There are four different BV testing methods: Gram-staining test using either Nugent's or Spiegel's criteria, gas liquid chromatography and clinical criteria. Two reviewers selected studies independently and extracted data on their characteristics, quality and accuracy with spontaneous preterm birth as the reference standard. Data on asymptomatic women and women with symptoms of threatened preterm labour were analysed separately. Data were pooled to produce summary estimates of likelihood ratios for positive (LR+) and negative (LR−) test results for the various types of tests. There were 18 primary articles, involving a total of 17 868 women. Meta-analysis of studies testing asymptomatic women in the second trimester showed that clinical criteria had an LR+ of 5.14 (95% confidence interval 4.44–6.15) and an LR− of 0.48 (0.42–0.55), Gram-staining (Nugent's criteria) had an LR+ of 1.64 (1.44–1.87) and an LR− of 0.88 (0.84–0.92), and Gram-staining (Spiegel's criteria) had an LR+ of 2.44 (1.36–4.98) and an LR− of 0.81 (0.64 to 1.01). Among symptomatic women, Gram-staining (Spiegel's criteria) had an LR+ of 1.29 (1.03–1.62) and an LR− of 0.85 (0.73–1.00).
BJOG An International Journal of Obstetrics & Gynaecology 07/2009; 23(s1):S34-S34. · 3.41 Impact Factor
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ABSTRACT: BACKGROUND: A new drug is approved for use if its effectiveness has been demonstrated. Recently decision-makers in a number of countries have begun to account for both the effectiveness and cost-effectiveness of new drugs. However, cost-effectiveness evidence lags behind the effectiveness data. OBJECTIVE: To explore the timeliness of delivering cost-effectiveness information about new drugs with established effectiveness and significant financial impact. METHODS: New drugs were identified, based on guidance documents and reports published by the National Institute for Clinical Excellence of England and Wales, and the following data were collected: dates of publication of first effectiveness and cost-effectiveness evidence, methodology of the cost-effectiveness analysis, funding of the research, etc. RESULTS: Guidance documents for the following new drugs/drug groups have been published by NICE by the end of 2000: taxanes for ovarian and breast cancer, proton pump inhibitors in the treatment of dyspepsia, glycoprotein IIb/IIIa inhibitors, methylphenidate for hyperactivity in childhood, zanamivir, and rosiglitazone for type II Diabetes Mellitus. The analysis of the evidence shows that the effectiveness of these drugs has been demonstrated in the last 12 years. However, cost-effectiveness evidence has been published for 70% of the drugs with an average delay of 3 years (range 0–10). The cost-effectiveness of those, introduced after 1995 (80% of all included drugs/drug groups), has been demonstrated using models only, if at all. CONCLUSIONS: Cost-effectiveness evidence is produced with a lag behind the effectiveness evidence. As a result, decision-makers are in a position of awaiting sound evidence while issuing guidance based on current inconclusive research results. The cost to society is discussed, and establishing the cost-effectiveness of new drugs alongside RCTs at an earlier stage of their development is suggested.
Value in Health 10/2008; 4(2):175 - 175. · 2.19 Impact Factor
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ABSTRACT: To determine the diagnostic accuracy and cost-effectiveness of duplex ultrasound (DUS), magnetic resonance angiography (MRA), and computed tomography angiography (CTA), as alternatives to contrast angiography (CA), for the assessment of lower limb peripheral arterial disease (PAD).
Ten electronic databases were searched in April 2004, with an update in May 2005. Six key journals and bibliographies of included studies were also searched and experts in the field were consulted.
Data extraction and quality assessment were performed in duplicate. Data were analysed according to test type and diagnostic threshold. For the economic analysis, a decision tree was developed and a probabilistic sensitivity analysis performed to incorporate statistical uncertainty into the cost-effectiveness analysis.
A total of 113 studies met the inclusion criteria (including six economic evaluations). For the detection of stenosis greater than 50% in the whole leg, contrast-enhanced (CE) MRA (14 studies) had the highest diagnostic accuracy, with sensitivity ranging from 92 to 99.5% and specificity from 64 to 99%. Two-dimensional (2D) time-of-flight (TOF) MRA (11 studies) was less accurate, with sensitivity ranging from 79 to 94% and specificity from 74 to 92%. 2D phase-contrast (PC) MRA (one study) had a sensitivity of 98% and specificity of 74%. CTA (seven studies) also appeared slightly inferior to CE MRA, with a sensitivity ranging from 89 to 99% and specificity from 83 to 97%, but better than DUS (28 studies), which had a sensitivity ranging from 80 to 98% and specificity from 89 to 99%. There was some indication that CE MRA and DUS were more accurate for detecting stenoses/occlusions above the knee than below the knee or in the pedal artery. The four studies of patient attitudes strongly suggested that patients preferred CE MRA to CA. CA was considered the most uncomfortable test, followed by CE MRA, with CTA being the least uncomfortable. Half of the patients (from a sample who did not suffer from claustrophobia and had no metallic implants) expressed no preference between undergoing TOF MRA or DUS; most of those who did express a preference favoured TOF MRA. In the 55 studies identified for adverse events, MRA was associated with the highest reported proportion. However, the most severe adverse events were more common in patients undergoing CA; although these were rare for both tests. The economic evaluation showed DUS dominated the other alternatives when the whole leg was assessed, by presenting higher effectiveness at a lower cost per quality-adjusted life-year (QALY; i.e. 13,646 pounds per QALY). When the assessment was limited to a section of the leg, either above the knee or below the knee, 2D TOF MRA was the most cost-effective preoperative diagnostic strategy. The incremental cost per QALY for below-the-knee comparisons was equal to 37,024 pounds when 2D TOF MRA was compared with DUS. For above-the-knee comparisons, 2D TOF MRA presented the lowest cost and slightly lower effectiveness compared with CE MRA, with a cost per QALY equal to 13,442 pounds.
The results of the review suggest that CE MRA has a better overall diagnostic accuracy than CTA or DUS, and that CE MRA is generally preferred by patients over CA. Where available, CE MRA may be a viable alternative to CA. The only controlled trial suggested that the results of DUS were comparable to those of CA, in terms of surgical planning and outcome. This finding conflicts with the results of diagnostic accuracy studies, which reported poor estimates of accuracy for DUS in comparison with CA. There was insufficient evidence to evaluate the usefulness of CTA for the assessment of PAD, particularly newer techniques. The results of the economic modelling suggest that for PAD patients for whom the whole leg is evaluated by a preoperative diagnostic test, DUS dominates the other alternatives by presenting higher effectiveness at a lower cost per QALY. However, when the analysis of stenosis is limited to a section of the leg, either above the knee or below the knee, 2D TOF MRA appears to be the most cost-effective preoperative diagnostic strategy. Further research is needed into a number of areas including the relative clinical effectiveness of the available imaging tests, in terms of surgical planning and postoperative outcome.
Health technology assessment (Winchester, England) 06/2007; 11(20):iii-iv, xi-xiii, 1-184. · 4.26 Impact Factor
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ABSTRACT: Antipsychotic therapy is the mainstay of treatment for people with schizophrenia. In recent years new or atypical antipsychotics have been introduced. These are less likely to produce movement disorders and raise serum prolactin. Researchers have suggested that molindone should be classified as an atypical antipsychotic.
To determine the effects of molindone compared with placebo, typical and other atypical antipsychotic drugs for schizophrenia and related psychoses.
For the original search we searched the following databases: Biological Abstracts (1980-1999), The Cochrane Library CENTRAL (Issue 1, 1999), The Cochrane Schizophrenia Group's Register (January 1999), CINAHL (1982-1999), EMBASE (1980-1999), MEDLINE (1966-1999), LILACS (1982-1999), PSYNDEX (1977-1999), and PsycLIT (1974-1999). We also searched pharmaceutical databases on the Dialog Corporation Datastar and Dialog and the references of all identified studies for further trials. Finally, we contacted the manufacturer of molindone and the authors of any relevant trials. For the update of this review, we searched The Cochrane Schizophrenia Group's Trials Register (August 2005).
We included all randomised controlled trials that compared molindone to other treatments for schizophrenia and schizophrenia-like psychoses.
We extracted data independently and analysed on an intention to treat basis calculating, for binary data, the fixed effect relative risk (RR), their 95% confidence intervals (CI), and the number needed to treat or harm (NNT or NNH). We excluded data if loss to follow up was greater than 50%.
We included fourteen studies. Duration ranged from very short (10 days) studies of the intramuscular preparation, to trials lasting over three months. For measures of global assessment, available data do not justify any conclusions on the comparative efficacy of molindone and placebo. When compared to other typical antipsychotics we found no evidence of a difference in effectiveness (doctors' 4 RCTs n=150, RR 1.13, CI 0.69 to 1.86; nurses 4RCTs n=146, RR 1.23, CI 0.82 to 1.86). Molindone is no more or less likely than typical drugs to cause movement disorders, but it does cause significantly more weight loss (2RCTs n=60 RR 2.78, CI 1.10 to 6.99, NNH 5 CI 2 to 77).
The strength of the evidence relating to this compound is limited, owing to small sample size, poor study design, limited outcomes and incomplete reporting. Molindone may be an effective antipsychotic but its adverse effect profile does not differ significantly from that of typical antipsychotics (apart from the event of weight loss). Data from this review suggest, at present, there is no evidence to suggest that it may have an atypical profile.
Cochrane database of systematic reviews (Online) 02/2007; · 5.72 Impact Factor
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ABSTRACT: To determine the accuracy of guaiac and immunochemical faecal occult blood tests (FOBTs) for the detection of colorectal cancer in an average-risk screening population.
Fifteen electronic databases, the internet, key journals and reference lists of included studies were searched. We included diagnostic accuracy studies that compared guaiac or immunochemical FOBTs with any reference standard, for the detection of colorectal cancer in an average-risk adult population, with sufficient data to construct a 2 x 2 table.
Fifty-nine studies were included. Thirty-three evaluated guaiac FOBTs, 35 immunochemical FOBTs and one evaluated sequential FOBTs. Sensitivities for the detection of all neoplasms ranged from 6.2% (specificity 98.0%) to 83.3% (specificity 98.4%) for guaiac FOBTs, and 5.4% (specificity 98.5%) to 62.6% (specificity 94.3%) for immunochemical FOBTs. Specificity ranged from 65.0% (sensitivity 44.1%) to 99.0% (sensitivity 19.3%) for guaiac FOBTs, and 89.4% (sensitivity 30.3%) to 98.5% (sensitivity 5.4%) for immunochemical FOBTs. Diagnostic case-control studies generally reported higher sensitivities. Sensitivities were higher for the detection of CRC, and lower for adenomas, in both the diagnostic cohort and diagnostic case-control studies for both guaiac and immunochemical FOBTs.
Immudia HemSp appeared to be the most accurate immunochemical FOBT, however, there was no clear evidence to suggest whether guaiac or immunochemical FOBTs performed better, either from direct or indirect comparisons. Poor reporting of data limited the scope of this review, and the use the Standards for Reporting of Diagnostic Accuracy guidelines is recommended for reporting future diagnostic accuracy studies.
Journal of Medical Screening 02/2007; 14(3):132-7. · 1.69 Impact Factor
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ABSTRACT: To determine the diagnostic accuracy of tests for detecting urinary tract infection (UTI) in children under 5 years of age and to evaluate the effectiveness of tests used to investigate further children with confirmed UTI. Also, to evaluate the effectiveness of following up children with UTI and the cost-effectiveness of diagnostic and imaging tests for the diagnosis and follow-up of UTI in children under 5. An additional objective was to develop a preliminary diagnostic algorithm for healthcare professionals.
Electronic databases were searched up to the end of 2002/early 2003. Consultation with experts in the field.
A systematic review was undertaken using published guidelines and results were analysed according to test grouping: diagnosis of UTI and further investigation of UTI. The cost-effectiveness results from existing evaluations were synthesised. A separate cost-effectiveness model was developed using the best available evidence, in part derived from the results of the systematic review, to illustrate the potential cost-effectiveness of some alternative management strategies in a UK setting. The results of the systematic review were used to propose diagnostic algorithms for the diagnosis and further investigation of UTI in children. Economic analyses did not contribute directly to the development of these algorithms.
The studies included in the review provided very little data on the accuracy of clinical investigations for the diagnosis of UTI, and criteria for clinical suspicion of UTI were not further defined. The majority of studies included in the review found that clean voided midstream urine (CVU) samples had similar accuracy to suprapubic aspiration (SPA) samples when cultured with the advantage of being a non-invasive collection method that can be used in the GP's surgery. Pad, nappy or bag specimens may be appropriate methods for obtaining a urine sample in non-toilet-trained children, although only limited data were available. Although the glucose test was reported to have the highest accuracy in terms of both ruling in and ruling out disease, only a limited number of studies of this test were included and these were conducted over 30 years ago. Dipstick tests are easy to perform in the GP's surgery, give an immediate result and are relatively cheap. The results of the systematic review showed that a dipstick for leucocyte esterase (LE) and nitrite, where both test results are interpreted in combination, was a good test both for ruling in (both positive) and ruling out (both negative) a UTI. A dipstick positive for either LE or nitrite and negative for the other provides inconclusive diagnostic information and further testing is therefore required in these patients. Microscopy is more time consuming and expensive to perform than a dipstick test, but potentially quicker and cheaper than culture. As with dipstick tests, a combination of microscopy for pyuria and bacteriuria can be used accurately to rule in and rule out a UTI. An indeterminate test result is again obtained if microscopy is positive for either pyuria or bacteriuria, and negative for the other. Confirmatory culture is required in these patients. In patients considered to have a UTI, further culture to determine antibiotic sensitivities may be an option to inform treatment decisions. Only one study satisfied the inclusion criteria of the economic review and the review highlighted a number of potential limitations of this study for NHS decision-making. A separate decision-analytic model was therefore developed to provide a more reliable estimate of the optimal strategy regarding the diagnosis and further investigation of children under 5 with suspected UTI from the perspective of the NHS. The economic model found that the optimal diagnostic strategy for children presenting with symptoms suggestive of UTI depends on a number of key factors. These included the relevant subgroup of children concerned, in terms of gender and age, and the health service's maximum willingness to pay for an additional quality-adjusted life-year.
The results of the systematic review were used to derive an algorithm for the diagnosis of UTI in children under 5. This algorithm represents the conclusions of the review in terms of effective practice. There were insufficient data to propose an algorithm for the further investigation of UTI in children under 5. The quality assessment highlighted several areas that could be improved upon in future diagnostic accuracy studies.
Health technology assessment (Winchester, England) 11/2006; 10(36):iii-iv, xi-xiii, 1-154. · 4.26 Impact Factor
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ABSTRACT: To determine the most effective diagnostic strategy for the investigation of microscopic and macroscopic haematuria in adults.
Electronic databases from inception to October 2003, updated in August 2004.
A systematic review was undertaken according to published guidelines. Decision analytic modelling was undertaken, based on the findings of the review, expert opinion and additional information from the literature, to assess the relative cost-effectiveness of plausible alternative tests that are part of diagnostic algorithms for haematuria.
A total of 118 studies met the inclusion criteria. No studies that evaluated the effectiveness of diagnostic algorithms for haematuria or the effectiveness of screening for haematuria or investigating its underlying cause were identified. Eighteen out of 19 identified studies evaluated dipstick tests and data from these suggested that these are moderately useful in establishing the presence of, but cannot be used to rule out, haematuria. Six studies using haematuria as a test for the presence of a disease indicated that the detection of microhaematuria cannot alone be considered a useful test either to rule in or rule out the presence of a significant underlying pathology (urinary calculi or bladder cancer). Forty-eight of 80 studies addressed methods to localise the source of bleeding (renal or lower urinary tract). The methods and thresholds described in these studies varied greatly, precluding any estimate of a 'best performance' threshold that could be applied across patient groups. However, studies of red blood cell morphology that used a cut-off value of 80% dysmorphic cells for glomerular disease reported consistently high specificities (potentially useful in ruling in a renal cause for haematuria). The reported sensitivities were generally low. Twenty-eight studies included data on the accuracy of laboratory tests (tumour markers, cytology) for the diagnosis of bladder cancer. The majority of tumour marker studies evaluated nuclear matrix protein 22 or bladder tumour antigen. The sensitivity and specificity ranges suggested that neither of these would be useful either for diagnosing bladder cancer or for ruling out patients for further investigation (cystoscopy). However, the evidence remains sparse and the diagnostic accuracy estimates varied widely between studies. Fifteen studies evaluating urine cytology as a test for urinary tract malignancies were heterogeneous and poorly reported. The calculated specificity values were generally high, suggesting some possible utility in confirming malignancy. However, the evidence suggests that urine cytology has no application in ruling out malignancy or excluding patients from further investigation. Fifteen studies evaluated imaging techniques [computed tomography (CT), intravenous urography (IVU) or ultrasound scanning (US)] to detect the underlying cause of haematuria. The target condition and the reference standard varied greatly between these studies. The diagnostic accuracy data for several individual studies appeared promising but meaningful comparison of the available imaging technologies was impossible. Eight studies met the inclusion criteria but addressed different parts of the diagnostic chain (e.g. screening programmes, laboratory investigations, full urological work-up). No single study addressed the complete diagnostic process. The review also highlighted a number of methodological limitations of these studies, including their lack of generalisability to the UK context. Separate decision analytic models were therefore developed to progress estimation of the optimal strategy for the diagnostic management of haematuria. The economic model for the detection of microhaematuria found that immediate microscopy following a positive dipstick test would improve diagnostic efficiency as it eliminates the high number of false positives produced by dipstick testing. Strategies that use routine microscopy may be associated with high numbers of false results, but evidence was lacking regarding the accuracy of routine microscopy and estimates were adopted for the model. The model for imaging the upper urinary tract showed that US detects more tumours than IVU at one-third of the cost, and is also associated with fewer false results. For any cause of haematuria, CT was shown to have a mean incremental cost-effectiveness ratio of pounds sterling 9939 in comparison with the next best option, US. When US is followed up with CT for negative results with persistent haematuria, it dominates the initial use of CT alone, with a saving of pounds sterling 235,000 for the evaluation of 1000 patients. The model for investigation of the lower urinary tract showed that for low-risk patients the use of immediate cystoscopy could be avoided if cystoscopy were used for follow-up patients with a negative initial test using tumour markers and/or cytology, resulting in a saving of pounds sterling 483,000 for the evaluation of 1000 patients. The clinical and economic impact on delayed detection of both upper and lower urinary tract tumours through the use of follow-up testing should be evaluated in future studies.
There are insufficient data currently available to derive an evidence-based algorithm of the diagnostic pathway for haematuria. A hypothetical algorithm based on the opinion and practice of clinical experts in the review team, other published algorithms and the results of economic modelling is presented in this report. This algorithm is presented, for comparative purposes, alongside current US and UK guidelines. The ideas contained in these algorithms and the specific questions outlined should form the basis of future research. Quality assessment of the diagnostic accuracy studies included in this review highlighted several areas of deficiency.
Health technology assessment (Winchester, England) 07/2006; 10(18):iii-iv, xi-259. · 4.26 Impact Factor
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ABSTRACT: To review the effectiveness and/or accuracy, cost-effectiveness, and predictive value of neuroimaging of the cerebral cortex to visualise the seizure focus in people with refractory epilepsy being considered for surgery.
Electronic databases, Internet searches, hand searching and consultation with experts.
A systematic review was undertaken according to published guidelines. Results of diagnostic accuracy studies were analysed according to the imaging test evaluated. For each study the proportion of patients who were correctly localised, not localised, partially localised or incorrectly localised by the index test was calculated. Due to the heterogeneity present between studies, statistical pooling was not performed. Instead, a narrative synthesis of results is presented. For studies using multivariate analysis to look at the association of neuroimaging findings and outcome following surgery, all factors considered in the analyses were presented. Studies were grouped according to the neuroimaging technique investigated and the findings discussed with reference to possible sources of heterogeneity between studies.
No randomised controlled trials (RCTs) were identified, with the majority of studies evaluating the diagnostic accuracy of various imaging techniques in the localisation of epileptic seizure foci. There was significant heterogeneity (p<0.05) between studies for at least one of the localisation categories (correctly localised, not localised, partially localised and incorrectly localised) for all imaging techniques. Possible explanations for this heterogeneity include differing study designs, index test characteristics, reference standards and population characteristics. Test performance was more promising in studies restricted to patients with temporal lobe epilepsy. Ictal single photon emission computed tomography (SPECT) generally had more correctly localising (70--100%) and fewer non-localising (0--7%) scans than other techniques evaluated in patients with temporal lobe epilepsy. Results for computed tomography and interictal SPECT suggest that these tests are relatively poor at localising the seizure focus. Volumeric magnetic resonance imaging (MRI) and position emission tomography (PET) appear promising, and subtraction ictal single photon emission computed tomography co-registered to magnetic resonance imaging (SISCOM) and magnetic resonance spectrosopy (MRS) less promising than ictal SPECT, but these technologies have been assessed in fewer studies. T2 relaxometry was reported in only one small study with inconclusive results. Seventeen studies (33 evaluations) provided sufficient data on the association of a localised scan with outcome following surgery to calculate a relative risk. The majority of evaluations (24/33) suggested that patients with a correctly or partially localised scan had a better outcome following surgery than those with an incorrectly localised or non-localised scan. However, this association was statistically significant in only three studies, two evaluating routine MRI [(relative risk (RR) 2.74, 95% confidence interval (CI): 1.32 to 5.67; RR 1.28, 95% CI: 1.00 to 1.63] and the other SISCOM (RR 2.12, 95% CI: 1.01, 4.44). Nine studies used multivariate analysis to investigate the association of MRI (7 studies), MRS and volumetric MRI (1 study), PET (3 studies), SPECT (1 study) and SISCOM (3 studies) with the outcome following surgery. There was a trend for localisation of abnormalities to be associated with a beneficial outcome.
Due to the limitations of the included studies, the results of this review do little to inform clinical practice, with insufficient evidence regarding effectiveness and cost-effectiveness of imaging techniques in the work-up for epilepsy surgery. Given the inadequacy of existing data, there is a pressing need for studies investigating the utility of imaging techniques in the work up for epilepsy surgery. The most reliable method to achieve this is the RCT, which could examine the single tests or combinations of tests on patient outcome. The authors suggest that it is important that clinicians, patient groups, policy makers and healthcare/research funders meet and debate the most appropriate way to investigate these technologies.
Health technology assessment (Winchester, England) 02/2006; 10(4):1-250, iii-iv. · 4.26 Impact Factor
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ABSTRACT: To determine the accuracy with which the absence of fetal breathing movements on ultrasound examination predicts spontaneous preterm birth in women with threatened preterm labor.
Data sources included Medline, Embase, Pascal, Biosis, Cochrane Library, Medion, National Research Register, SciSearch, conference papers, and manual searching of bibliographies of known primary and review articles. A study was selected if it used absence of fetal breathing movements on ultrasound to predict spontaneous preterm birth in women with threatened preterm labor but before advanced cervical dilatation. Two reviewers independently selected studies and extracted data on their characteristics, quality and accuracy. Accuracy data were used to form 2 x 2 contingency tables with birth within 48 h and within 7 days of testing as the reference standards. Likelihood ratios for a positive test (LR+) and negative test (LR-) were calculated as a measure of accuracy.
There were eight studies, which included a total of 328 women, evaluating the accuracy of absence of fetal breathing movements in predicting spontaneous preterm birth in women with threatened preterm labor. There were differences in the methodological quality among the included studies. All were lacking in one or more item that make up an ideal test accuracy study. For women presenting with threatened preterm labor, meta-analysis showed a summary LR+ of 14.80 (95% CI, 6.30-34.79) with a corresponding summary LR- of 0.46 (95% CI, 0.36-0.58) for predicting preterm birth within 7 days, and summary LR+ of 7.84 (95% CI, 1.12-54.99) and summary LR- of 0.25 (95% CI, 0.13-0.48) for predicting preterm birth within 48 h of testing.
Absence of fetal breathing movements has the potential to be a useful test in predicting preterm birth both within 7 days and within 48 h of testing. However, the available studies were deficient in their sample size and quality of methodology. Future research should be undertaken to evaluate this technology and to address the methodological deficiencies.
Ultrasound in Obstetrics and Gynecology 08/2004; 24(1):94-100. · 3.01 Impact Factor
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ABSTRACT: To develop a quality assessment tool which will be used in systematic reviews to assess the quality of primary studies of diagnostic accuracy.
Electronic databases including MEDLINE, EMBASE, BIOSIS and the methodological databases of both CRD and the Cochrane Collaboration.
Three systematic reviews were conducted to provide an evidence base for the development of the quality assessment tool. A Delphi procedure was used to develop the quality assessment tool and the information provided by the reviews was incorporated into this. A panel of nine experts in the area of diagnostic accuracy studies took part in the Delphi procedure to agree on the items to be included in the tool. Panel members were also asked to provide feedback on various other items and whether they would like to see the development of additional topic and design specific items. The Delphi procedure produced the quality assessment tool, named the QUADAS tool, which consisted of 14 items. A background document was produced describing each item included in the tool and how each of the items should be scored.
The reviews produced 28 possible items for inclusion in the quality assessment tool. It was found that the sources of bias supported by the most empirical evidence were variation by clinical and demographic subgroups, disease prevalence/severity, partial verification bias, clinical review bias and observer/instrument variation. There was also some evidence of bias for the effects of distorted selection of participants, absent or inappropriate reference standard, differential verification bias and review bias. The evidence for the effects of other sources of bias was insufficient to draw conclusions. The third review found that only one item, the avoidance of review bias, was included in more than 75% of tools. Spectrum composition, population recruitment, absent or inappropriate reference standard and verification bias were each included in 50-75% of tools. Other items were included in less than 50% of tools. The second review found that the quality assessment tool should have the potential to be discussed narratively, reported in a tabular summary, used as recommendations for future research, used to conduct sensitivity or regression analyses and used as criteria for inclusion in the review or a primary analysis. This suggested that some distinction is needed between high- and low-quality studies. Component analysis was considered the best approach to incorporate quality into systematic reviews of diagnostic studies and this was taken into consideration when developing the tool.
This project produced an evidence-based quality assessment tool to be used in systematic reviews of diagnostic accuracy studies. Through the various stages of the project the current lack of such a tool and the need for a systematically developed validated tool were demonstrated. Further work to validate the tool continues beyond the scope of this project. The further development of the tool by the addition of design- and topic-specific criteria is proposed.
Health technology assessment (Winchester, England) 07/2004; 8(25):iii, 1-234. · 4.26 Impact Factor
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ABSTRACT: This review aims to determine the accuracy with which published risk scores predict spontaneous preterm birth in pregnant women. Studies were identified without language restrictions through nine different databases (up to June 2002), and manual searching of bibliographies of known primary and review articles. Two reviewers selected studies independently and extracted data on their characteristics, quality and accuracy. Accuracy data were used to form 2 x 2 contingency tables of the results of risk scoring with spontaneous preterm birth as the reference standard. Heterogeneity was assessed and its reasons were explored. Summary estimates of accuracy were produced within clinically appropriate subgroups. There were 19 primary accuracy articles that met the selection criteria, including a total of 67390 women. There are 12 different risk-scoring systems, the one developed by Creasy being the most commonly evaluated. Quality features of an ideal study, such as blinding and consecutive enrolment, were frequently missing from the included studies, no study fulfilled all criteria for high quality study, and there was heterogeneity between their accuracy estimates. The reference standard most often used was birth before 37 weeks' gestation. The point estimates for the likelihood ratios (LRs) varied widely among the studies. LRs for an abnormal score (LR+) ranged from 1.0 (95% confidence interval (CI) 0.6-1.4) to 38.8 (95% CI 23.5-63.9) while that for a normal score (LR-) ranged from 0.1 (95% CI 0.02-0.6) to 1.2 (95% CI 0.9-1.6). In otherwise asymptomatic women, risk scoring in early pregnancy has a wide range of accuracy in predicting spontaneous preterm birth before 37 weeks' gestation. The evidence is of a relatively poor quality and lacks clinically important reference standards.
Journal of Obstetrics and Gynaecology 07/2004; 24(4):343-59. · 0.54 Impact Factor
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ABSTRACT: This review investigates the accuracy with which transvaginal cervical sonography predicts spontaneous preterm birth. Published studies were identified without language restrictions through nine different databases and manual searching of bibliographies of known primary and review articles. Studies were selected if they undertook antenatal transvaginal sonographic cervical assessment among a population of pregnant women with known gestational age of delivery. There were 46 primary articles, which included a total of 31,577 women, consisting of 33 studies in asymptomatic and 13 studies in symptomatic women. Data were extracted for the studies' characteristics and quality. Accuracy data were used to form 2 x 2 contingency tables for various cervical length measurements with birth before 32, 34 and 37 weeks' gestation as the reference standards. Data were stratified according to singleton or twin pregnancy, gestational age at testing, cervical length threshold, and the various reference standards, and were pooled to produce summary estimates of likelihood ratios (LRs). Our review showed that transvaginal cervical sonography identifies women who are at higher risk of spontaneous preterm birth, although there was a wide variation amongst studies with respect to gestational age at testing, definition of threshold of abnormality and definition of reference standard. The most commonly reported sub-group was testing of asymptomatic women at < 20 weeks' gestation using a threshold cervical length of 25 mm with spontaneous preterm birth before 34 weeks' gestation as the reference standard. The summary LR+ for this group was 6.29 (95% CI, 3.29-12.02), with corresponding LR- of 0.79 (95% CI, 0.65-0.95). Both cervical length measurement and funneling, whether alone or in combination, appear to be useful (depending on the threshold chosen to define the abnormality) in predicting spontaneous preterm birth in asymptomatic women. For symptomatic women there was a paucity of data, although the degree of funneling appeared to be predictive of spontaneous preterm birth.
Ultrasound in Obstetrics and Gynecology 09/2003; 22(3):305-22. · 3.01 Impact Factor
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Ultrasound in Obstetrics and Gynecology 08/2003; 22(S1):147 - 147. · 3.01 Impact Factor
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Health technology assessment (Winchester, England) 02/2003; 7(13):1-193. · 4.26 Impact Factor
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Quality and Safety in Health Care 07/2002; 11(2):189-94. · 1.68 Impact Factor
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ABSTRACT: Following the election of the British government in May 1997, a policy document outlining proposals to improve the health of the nation was published. This document placed a major emphasis on reducing inequalities in health and recognised the continuing poor state of oral health in deprived communities. However, whilst acknowledging the benefits of water fluoridation as a caries preventive measure, the Department of Health suggested that most of the research had been carried out some years ago and furthermore, recognised that strong views were held both for and against fluoridation.
British dental journal 06/2002; 192(9):495-7. · 0.92 Impact Factor
