Biomedical subjects

Mark Helfand

Publications and source records attributed to Mark Helfand.

At least 19 recordsLinked to original sources

PubMed2006

Methodological shortcomings predicted lower harm estimates in one of two sets of studies of clinical interventions.

OBJECTIVES: High quality harms data are necessary to appropriately assess the balance between benefits and harms of interventions. Little is known, however, about whether perceived methodological shortcomings are associated with lower estimates of harms. STUDY DESIGN AND SETTING: Studies reporting harms associated with carotid endarterectomy (CEA) and rofecoxib were identified using published systematic reviews. A standardized abstraction form, including eight predefined criteria for assessing the quality of harms reporting, was used to extract data. Univariate and multivariate analyses were performed to empirically evaluate the association between quality criteria and estimates of harms. RESULTS: In 111 studies of CEA, meeting five of the eight-quality criteria was associated with significantly higher adverse event rates. A quality-rating instrument with four criteria predicted adverse events (5.7% in studies rated "adequate," compared to 3.9% in studies rated "inadequate" [P=0.0003]). In multivariate analyses, the quality-rating assignment remained significant when controlling for other clinical and study-related variables. Different quality criteria, however, predicted estimates of risk for myocardial infarction in 16 trials of rofecoxib. CONCLUSION: The presence of methodological shortcomings can predict lower estimates of serious harms. Clinicians and researchers should consider methodological shortcomings when evaluating estimates of harms associated with clinical interventions.

Biomedical Research↗

PubMed2006

Diagnosis, access and outcomes: Update of a systematic review of telemedicine services.

Telemedicine services are being increasingly used. Although insurers and other payers are covering some services in the USA, the rationale for these coverage decisions is not always evidence-based. We reviewed the literature for telemedicine services that substitute for face-to-face medical diagnosis and treatment. We focused on three types of telemedicine services: store-and-forward, home-based and office/hospital-based services. Studies were included if they were relevant to at least one of the three study areas, addressed at least one key question and contained reported results. We excluded articles that did not study a service requiring face-to-face encounters (i.e. teleradiology was excluded). Our search initially identified 4083 citations. After review, 597 were judged to be potentially relevant at the title/abstract level. Following a full-text review, 106 studies were included. Store-and-forward services have been studied in many specialties, the most common being dermatology, wound care and ophthalmology. The evidence for their efficacy is mixed. Several limited studies showed the benefits of home-based telemedicine interventions in chronic diseases. Studies of office/hospital-based telemedicine suggest that telemedicine is most effective for verbal interactions, e.g. videoconferencing for diagnosis and treatment in specialties like neurology and psychiatry. There are still significant gaps in the evidence base between where telemedicine is used and where its use is supported by high-quality evidence. Further well-designed research is necessary to understand how best to deploy telemedicine services in health care.

Delivery of Health Care↗

PubMed2006

Screening for developmental dysplasia of the hip: a systematic literature review for the US Preventive Services Task Force.

BACKGROUND: Developmental dysplasia of the hip (DDH) represents a spectrum of anatomic abnormalities that can result in permanent disability. OBJECTIVE: We sought to gather and synthesize the published evidence regarding screening for DDH by primary care providers. METHODS: We performed a systematic review of the literature by using a best-evidence approach as used by the US Preventive Services Task Force. The review focused on screening relevant to primary care in infants from birth to 6 months of age and on interventions used in infants before 1 year of age. RESULTS: The literature on screening and interventions for DDH suffers from significant methodologic shortcomings. No published trials directly link screening to improved functional outcomes. Clinical examination and ultrasound identify somewhat different groups of newborns who are at risk for DDH. A significant proportion of hip abnormalities identified through clinical examination or ultrasound in the newborn period will spontaneously resolve. Very few studies examine the functional outcomes of patients who have undergone therapy for DDH. Because of the high rate and unpredictable nature of spontaneous resolution of DDH and the absence of rigorous comparative studies, the effectiveness of interventions is not known. All surgical and nonsurgical interventions have been associated with avascular necrosis of the femoral head, the most common and most severe harm associated with all treatments of DDH. CONCLUSIONS: Screening with clinical examination or ultrasound can identify newborns at increased risk for DDH, but because of the high rate of spontaneous resolution of neonatal hip instability and dysplasia and the lack of evidence of the effectiveness of intervention on functional outcomes, the net benefits of screening are not clear.

Early Diagnosis↗

PubMed2006

Screening for elevated lead levels in childhood and pregnancy: an updated summary of evidence for the US Preventive Services Task Force.

BACKGROUND: In 1996, the US Preventive Services Task Force provided recommendations for routine screening of asymptomatic children and pregnant women for elevated blood lead levels. This review updates the evidence for the benefits and harms of screening and intervention for elevated blood lead in asymptomatic children and pregnant women. METHODS: We searched Medline, reference lists of review articles, and tables of contents of leading pediatric journals for studies published in 1995 or later that contained new information about the prevalence, diagnosis, natural course, or treatment of elevated lead levels in asymptomatic children aged 1 to 5 years and pregnant women. RESULTS: The prevalence of elevated blood lead levels among children and women in the United States, like that in the general population, continues to decline sharply, primarily because of marked reductions in environmental exposure, but still varies substantially among different communities and populations. Similar to the findings in 1996, our searches did not identify direct evidence from controlled studies that screening children for elevated blood lead levels results in improved health outcomes, and there was no direct evidence identified from controlled studies that screening improves pregnancy or perinatal outcomes. No new relevant information regarding the accuracy of screening for lead toxicity was identified during the update, and we did not identify evidence that demonstrates that universal screening for blood lead results in better clinical outcomes than targeted screening. Substantial new relevant information regarding the adverse effects of screening and interventions was not identified. CONCLUSIONS: There is no persuasive evidence that screening for elevated lead levels in asymptomatic children will improve clinical outcomes. For those children who are screened and found to have elevated levels, there is conflicting evidence demonstrating the clinical effectiveness of early detection and intervention.

Blood Chemical Analysis↗

PubMed2005

Challenges in systematic reviews that evaluate drug efficacy or effectiveness.

Increasingly, consumers, clinicians, regulatory bodies, and insurers are using systematic reviews of drug interventions to select treatments and set policies. Although a systematic review cannot provide all the information a clinician needs to make an informed choice for therapy, it can help decision makers distinguish what claims about effectiveness are based on evidence, identify critical information gaps, describe features of the evidence that limit applicability in practice, and address whether drug effectiveness differs for particular subgroups of patients. To improve the relevance and validity of reviews of drug therapies, reviewers need to delineate clinically important subgroups, specific aims of therapy, and most important outcomes. They may need to find unpublished trials, studies other than direct comparator (head-to-head) trials, and additional details of published trials from pharmaceutical manufacturers and regulatory agencies. In this paper, we address ways to formulate questions relevant to specific clinical therapeutic aims; discuss types of studies to include in drug efficacy and effectiveness reviews and how to find them; and describe ways to assess applicability of studies to actual practice.

Clinical Trials as Topic↗

PubMed2005

Challenges in systematic reviews that assess treatment harms.

An evidence synthesis of a medical intervention should assess the balance of benefits and harms. Investigators performing systematic reviews of harms face challenges in finding data, rating the quality of harms reporting, and synthesizing and displaying data from different sources. Systematic reviews of harms often rely primarily on published clinical trials. Identifying important harms of treatment and quantifying the risk associated with them, however, often require a broader range of data sources, including unpublished trials, observational studies, and unpublished information on published trials submitted to the U.S. Food and Drug Administration. Each source of data has some potential for yielding important information. Criteria for judging the quality of harms assessment and reporting are still in their early stages of development. Investigators conducting systematic reviews of harms should consider empirically validating the criteria they use to judge the validity of studies reporting harms. Synthesizing harms data from different sources requires careful consideration of internal validity, applicability, and sources of heterogeneity. This article highlights examples of approaches to methodologic issues associated with performing systematic reviews of harms from 96 Evidence-based Practice Center evidence reports.

Evidence-Based Medicine↗

PubMed2005

Economic comparison of diagnostic approaches for evaluating osteoporosis in older women.

Of the technologies available, dual-energy X-ray absorptiometry of the hip or femoral neck (DXA-FN) is the best predictor of hip fractures. Diagnostic approaches utilizing measures of peripheral sites with office-based technology, such as calcaneal quantitative ultrasound (QUS), may reduce costs although clinical and economic outcomes have not been evaluated. The objective was to compare three approaches for diagnosing osteoporosis in older women. The design was a decision-analytic model using diagnostic measures and clinical and economic outcomes from the Study of Osteoporotic Fractures, a prospective cohort of older white women that measured BMD and QUS and assessed fracture outcomes. The setting and patients were a hypothetical cohort of older white women presenting for diagnosis of osteoporosis. For the diagnostic and treatment alternatives, three diagnostic approaches-DXA-FN alone, QUS alone and a sequential approach (first QUS, then DXA-FN for those with low values for QUS)-were compared to no diagnosis. The outcome measures were the number of women identified for treatment, number of hip fractures prevented following diagnosis and subsequent treatment, number of women needed to treat to prevent one hip fracture and total direct medical costs. The sequential approach identified fewer women to treat, prevented more hip fractures and incurred lower total costs than using DXA alone. Diagnosis with QUS alone identified more women to treat and incurred higher total costs than DXA alone under most conditions. Compared to other approaches for diagnosing osteoporosis, sequential use of QUS followed by DXA resulted in fewer women treated and lower total costs.

Absorptiometry, Photon↗

PubMed2005

Incorporating information about cost-effectiveness into evidence-based decision-making: the evidence-based practice center (EPC) model.

RATIONALE: There is a pressing need for guidance on how to incorporate economic information into evidence-based decision-making. Such guidance should take account of the quality and relevance of economic evaluations. OBJECTIVE: To summarize lessons learned in integrating information from decision analyses and cost-effectiveness analyses. KEY ISSUES: Several methods used by the Evidence-Based Practice Centers (EPCs) to conduct systematic reviews are applicable to assessing economic studies. We discuss methods to identify key questions for the review of economic studies. Reviews should assess how an economic model incorporates clinical logic and handles uncertainty about effectiveness. As is the case for metaanalysis of interventions, qualitative or quantitative synthesis of economic studies should explore heterogeneity to identify key uncertainties underlying divergent results as well as unsuspected sources of bias. CONCLUSIONS: Applying EPC methods to synthesis of economic information can increase their relevance to clinicians and policymakers and inform decisions that require tradeoffs between effectiveness and harms of interventions.

Cost-Benefit Analysis↗

PubMed2005

The evaluation of rectal bleeding in adults. A cost-effectiveness analysis comparing four diagnostic strategies.

BACKGROUND: Though primary care patients commonly present with rectal bleeding, the optimal evaluation strategy remains unknown. OBJECTIVE: To compare the cost-effectiveness of four diagnostic strategies in the evaluation of rectal bleeding. DESIGN: Cost-effectiveness analysis using a Markov decision model. DATA SOURCES: Systematic review of the literature, Medicare reimbursement data, Surveillance, Epidemiology, and End Results (SEER) Cancer Registry. TARGET POPULATION: Patients over age 40 with otherwise asymptomatic rectal bleeding. TIME HORIZON: The patient's lifetime. PERSPECTIVE: Modified societal perspective. INTERVENTIONS: Watchful waiting, flexible sigmoidoscopy, flexible sigmoidoscopy followed by air contrast barium enema (FS+ACBE), and colonoscopy. OUTCOME MEASURES: Incremental cost-effectiveness ratio. RESULTS OF BASE-CASE ANALYSIS: The incremental cost-effectiveness ratio for colonoscopy compared with flexible sigmoidoscopy was 5,480 dollars per quality-adjusted year of life saved (QALY). Watchful waiting and FS+ACBE were more expensive and less effective than colonoscopy. RESULTS OF SENSITIVITY ANALYSES: The cost of colonoscopy was reduced to 1,686 dollars per QALY when age at entry was changed to 45. Watchful waiting became the least expensive strategy when community procedure charges replaced Medicare costs, when age at entry was maximized to 80, or when the prevalence of polyps was lowered to 7%, but the remaining strategies provided greater life expectancy at relatively low cost. The strategy of FS+ACBE remained more expensive and less effective in all analyses. In the remaining sensitivity analyses, the incremental cost-effectiveness of colonoscopy compared with flexible sigmoidoscopy never rose above 34,000 dollars. CONCLUSIONS: Colonoscopy is a cost-effective method to evaluate otherwise asymptomatic rectal bleeding, with a low cost per QALY compared to other strategies.

Adult↗

PubMed2005

Hyperbaric oxygen therapy for stroke: a systematic review of the evidence.

OBJECTIVE: To identify the benefits and harms of using hyperbaric oxygen therapy to treat acute or subacute stroke or the chronic effects of a stroke. We aimed to identify any gaps in the evidence to provide guidance for future research. DESIGN: A systematic review of the evidence. SEARCH STRATEGY: We searched MEDLINE, EMBASE, the Cochrane Library, HealthSTAR, CINAHL, MANTIS, bibliographic databases from professional societies and hyperbaric oxygen therapy practitioners, and reference lists. Databases were searched from inception to December 2003. INCLUSION CRITERIA STUDIES: Controlled clinical trials and observational studies published in English. PARTICIPANTS: Patients with ischaemic stroke in any inpatient or outpatient setting. OUTCOMES: Mortality, functional health outcomes and adverse events. DATA COLLECTION AND ANALYSIS: Using predetermined criteria, two reviewers assessed each study for inclusion, and abstracted data about study design, population, interventions, and outcomes. We assigned an overall quality rating (good, fair, or poor) based on internal validity. RESULTS: We identified only four randomized controlled trials and one controlled clinical trial. The best evidence shows no benefit to hyperbaric oxygen therapy in patients with stroke, but because the stage of patients enrolled (acute, subacute, or chronic), the documentation of type and severity of stroke, and the dosage of hyperbaric oxygen therapy given varied considerably, the generalizability of these results is limited. We identified 17 observational studies; all were poor quality. CONCLUSIONS: The overall evidence is insufficient to determine the effectiveness of hyperbaric oxygen therapy in any subgroup of stroke patients. To determine if hyperbaric oxygen therapy for stroke provides any benefit and that these outweigh potential harms, good quality studies are needed.

Brain Ischemia↗

PubMed2004

Systematic review of the incidence and consequences of uterine rupture in women with previous caesarean section.

OBJECTIVE: To evaluate the incidence and consequences of uterine rupture in women who have had a delivery by caesarean section. DESIGN: Systematic review. DATA SOURCES: Medline, HealthSTAR, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, National Centre for Reviews and Dissemination, reference lists, and national experts. Studies in all languages were eligible if published in full. REVIEW METHODS: Methodological quality was evaluated for each study by using criteria from the United States Preventive Services Task Force and the National Health Service Centre for Reviews and Dissemination. Uterine rupture was categorised as asymptomatic or symptomatic. RESULTS: We reviewed 568 full text articles to identify 71 potentially eligible studies, 21 of which were rated at least fair in quality. Compared with elective repeat caesarean delivery, trial of labour increased the risk of uterine rupture by 2.7 (95% confidence interval 0.73 to 4.73) per 1000 cases. No maternal deaths were related to rupture. For women attempting vaginal delivery, the additional risk of perinatal death from rupture of a uterine scar was 1.4 (0 to 9.8) per 10,000 and the additional risk of hysterectomy was 3.4 (0 to 12.6) per 10 000. The rates of asymptomatic uterine rupture in trial of labour and elective repeat caesarean did not differ significantly. CONCLUSIONS: Although the literature on uterine rupture is imprecise and inconsistent, existing studies indicate that 370 (213 to 1370) elective caesarean deliveries would need to be performed to prevent one symptomatic uterine rupture.

Cesarean Section↗

PubMed2004

Screening for hepatitis C virus infection: a review of the evidence for the U.S. Preventive Services Task Force.

BACKGROUND: Hepatitis C virus (HCV) is the most common bloodborne pathogen in the United States and is an important cause of patient morbidity and mortality, but it is unclear whether screening to identify asymptomatic infected persons is appropriate. PURPOSE: To synthesize the evidence on risks and benefits of screening for HCV infection. DATA SOURCES: MEDLINE (through February 2003), Cochrane Clinical Trials Registry (2002, Issue 2), reference lists, and experts. STUDY SELECTION: Controlled studies of screening and antiviral therapy and observational studies on other interventions, risk factors, accuracy of antibody testing, work-up, harms of biopsy, and long-term outcomes. DATA EXTRACTION: Using preset criteria, the authors assessed the quality of included studies and abstracted information about settings, patients, interventions, and outcomes. DATA SYNTHESIS: There are no published trials of screening for HCV infection. Approximately 2% of U.S. adults have HCV antibodies, with the majority having chronic infection. Risk factor assessment could identify adults at substantially higher risk. Antiviral treatment can result in a sustained virologic response rate of 54% to 56%, but no trials have been done specifically in asymptomatic patients likely to be identified by screening. Data are insufficient to determine whether treatment improves long-term outcomes. There are no data to estimate the benefit from counseling or immunizations. Although risks of biopsy and treatment appear minimal or self-limited, data on other adverse effects of screening, such as labeling or anxiety, are sparse. CONCLUSIONS: Antiviral treatment can successfully eradicate HCV, but data on long-term outcomes in populations likely to be identified by screening are lacking. Although the yield from targeted screening, particularly in intravenous drug users, would be substantially higher than in the general population, data are inadequate to accurately weigh the overall benefits and risks of screening in otherwise healthy asymptomatic adults.

Adult↗

PubMed2004

Screening for subclinical thyroid dysfunction in nonpregnant adults: a summary of the evidence for the U.S. Preventive Services Task Force.

BACKGROUND: Subclinical thyroid dysfunction is a risk factor for developing symptomatic thyroid disease. Advocates of screening argue that early treatment can prevent serious morbidity in individuals who are found to have laboratory evidence of subclinical thyroid dysfunction. PURPOSE: This article focuses on whether it is useful to order a thyroid function test for patients who have no history of thyroid disease and have few or no signs or symptoms of thyroid dysfunction. DATA SOURCES: A MEDLINE search, supplemented by searches of EMBASE and the Cochrane Library, reference lists, and a local database of thyroid-related articles. STUDY SELECTION: Controlled treatment studies that used thyroid-stimulating hormone (TSH) levels as an inclusion criterion and reported quality of life, symptoms, or lipid level outcomes were selected. Observational studies of the prevalence, progression, and consequences of subclinical thyroid dysfunction were also reviewed. DATA EXTRACTION: The quality of each trial was assessed by using preset criteria, and information about setting, patients, interventions, and outcomes was abstracted. DATA SYNTHESIS: The prevalence of unsuspected thyroid disease is lowest in men and highest in older women. Evidence regarding the efficacy of treatment in patients found by screening to have subclinical thyroid dysfunction is inconclusive. No trials of treatment of subclinical hyperthyroidism have been done. Several small, randomized trials of treatment of subclinical hypothyroidism have been done, but the results are inconclusive except in patients who have a history of treatment of Graves disease, a subgroup that is not a target of screening in the general population. Data on the adverse effects of broader use of L-thyroxine are sparse. CONCLUSION: It is uncertain whether treatment will improve quality of life in otherwise healthy patients who have abnormal TSH levels and normal free thyroxine levels.

Adult↗

PubMed2004

Hyperbaric oxygen therapy for traumatic brain injury: a systematic review of the evidence.

OBJECTIVE: To identify the benefits and harms of hyperbaric oxygen therapy (HBOT) to treat traumatic brain injury (TBI). DATA SOURCES: MEDLINE, EMBASE, the Cochrane Library, HealthSTAR, CINAHL, MANTIS, professional society databases, and reference lists. Databases were searched from inception through December 2003. STUDY SELECTION: We included English-language studies of patients with TBI given HBOT and evaluating functional health outcomes. DATA EXTRACTION: Data were abstracted by 1 reviewer and checked by a second. Study quality was rated as good, fair, or poor. DATA SYNTHESIS: Two fair-quality randomized controlled trials of patients with severe brain injury reported conflicting results. One found no difference in mortality (48% HBOT vs 55% control) or morbidity at 1 year. In young patients with brainstem contusion, significantly more regained consciousness at 1 month with HBOT (67%) than control (11%) (P<.03). The other found a significant decrease in mortality in the HBOT group at 1 year (17%) compared with controls (31%) (P=.037). This decrease in mortality was accompanied by an increase in proportion of patients with severe disability. Patients with intracranial pressure (ICP) greater than 20 mmHg or a Glasgow Coma Scale score of 4 to 6 had significantly lower mortality at 1 year than controls. Five observational studies did not provide better evidence of effectiveness or adverse events. Two indicated a potential for initially reducing elevated ICP in some patients. However, rebound elevations higher than pretreatment levels occurred in some patients. Adverse events, including seizures, pulmonary symptoms, and neurologic deterioration, were reported; however, no study systematically assessed adverse events, and none reported adverse events in control groups. CONCLUSIONS: The evidence for HBOT for TBI is insufficient to prove effectiveness or ineffectiveness, and more high-quality studies are needed. The evidence indicates that there is a small chance of a mortality benefit, which may depend on subgroup selection. The effect on functional status and the incidence and clinical significance of adverse effects are unclear.

Brain Injuries↗

PubMed2004

Comparative efficacy and safety of skeletal muscle relaxants for spasticity and musculoskeletal conditions: a systematic review.

Skeletal muscle relaxants are a heterogeneous group of medications used to treat two different types of underlying conditions: spasticity from upper motor neuron syndromes and muscular pain or spasms from peripheral musculoskeletal conditions. Although widely used for these indications, there appear to be gaps in our understanding of the comparative efficacy and safety of different skeletal muscle relaxants. This systematic review summarizes and assesses the evidence for the comparative efficacy and safety of skeletal muscle relaxants for spasticity and musculoskeletal conditions. Randomized trials (for comparative efficacy and adverse events) and observational studies (for adverse events only) that included oral medications classified as skeletal muscle relaxants by the FDA were sought using electronic databases, reference lists, and pharmaceutical company submissions. Searches were performed through January 2003. The validity of each included study was assessed using a data abstraction form and predefined criteria. An overall grade was allocated for the body of evidence for each key question. A total of 101 randomized trials were included in this review. No randomized trial was rated good quality, and there was little evidence of rigorous adverse event assessment in included trials or observational studies. There is fair evidence that baclofen, tizanidine, and dantrolene are effective compared to placebo in patients with spasticity (primarily multiple sclerosis). There is fair evidence that baclofen and tizanidine are roughly equivalent for efficacy in patients with spasticity, but insufficient evidence to determine the efficacy of dantrolene compared to baclofen or tizanidine. There is fair evidence that although the overall rate of adverse effects between tizanidine and baclofen is similar, tizanidine is associated with more dry mouth and baclofen with more weakness. There is fair evidence that cyclobenzaprine, carisoprodol, orphenadrine, and tizanidine are effective compared to placebo in patients with musculoskeletal conditions (primarily acute back or neck pain). Cyclobenzaprine has been evaluated in the most clinical trials and has consistently been found to be effective. There is very limited or inconsistent data regarding the effectiveness of metaxalone, methocarbamol, chlorzoxazone, baclofen, or dantrolene compared to placebo in patients with musculoskeletal conditions. There is insufficient evidence to determine the relative efficacy or safety of cyclobenzaprine, carisoprodol, orphenadrine, tizanidine, metaxalone, methocarbamol, and chlorzoxazone. Dantrolene, and to a lesser degree chlorzoxazone, have been associated with rare serious hepatotoxicity.

Clinical Trials as Topic↗

PubMed2004

Safety of vaginal birth after cesarean: a systematic review.

OBJECTIVE: To evaluate the benefits and harms of vaginal birth after cesarean compared with repeat cesarean delivery. DATA SOURCES: The computerized databases MEDLINE, EMBASE, HealthSTAR, Cochrane CENTRAL, and National Centre for Reviews and Dissemination Database of Abstracts of Reviews of Effectiveness, along with reference lists and national experts, were used to conduct this review. METHODS OF STUDY SELECTION: All studies that reported data for maternal or infant outcomes in women with prior cesarean delivery were eligible. Methodological quality was evaluated for each study with the criteria of the United States Preventive Services Task Force and the National Health Service Centre for Reviews and Dissemination. Twenty of 6,828 potentially relevant articles (55,506 patients) were included in the analysis. TABULATION, INTEGRATION, AND RESULTS: Two authors independently abstracted information on study design, sample size, participant characteristics, and maternal and fetal health outcomes by using a standardized protocol. Rates of vaginal delivery in women undergoing a trial of labor ranged from 60% to 82%. There was no significant difference in maternal deaths or hysterectomy between trial of labor and repeat cesarean. Uterine rupture was more common in the trial-of-labor group, but rates of asymptomatic uterine dehiscence did not differ. Studies conflicted on the effect of induction of labor on these outcomes. Data regarding infant outcomes were poor. CONCLUSION: Safety in childbirth for women with prior cesarean is a major public health concern. Methodological deficiencies in the literature evaluating the relative safety of vaginal birth after cesarean compared with repeat cesarean delivery are striking. The identification of high-risk and low-risk groups of women and settings for morbidity remains a key research priority.

Cesarean Section, Repeat↗

PubMed2003

The cost-effectiveness of screening mammography beyond age 65 years: a systematic review for the U.S. Preventive Services Task Force.

PURPOSE: There are few data on the effects of disease biology and competing mortality on the effectiveness of screening women for breast cancer after age 65 years. The authors performed a review to determine the costs and benefits of mammography screening after age 65 years. DATA SOURCES: Cost-effectiveness articles published between January 1989 and March 2002. STUDY SELECTION: Studies were identified by using MEDLINE and the National Health Service Economic Evaluation Database. The authors included research on screening after age 65 years conducted from a societal or government perspective; reviews and analyses of other technologies were excluded. DATA SYNTHESIS: 115 studies were identified and 10 met inclusion criteria. One study modeled age-dependent assumptions of disease biology. No study fully captured the potential harms of screening, including anxiety associated with false-positive results, overdiagnosis, and previous knowledge of cancer or living longer with the consequences of treatment. Studies differed in the specific strategies compared and in analytic approaches. On average, extending biennial screening to age 75 or 80 years was estimated to cost 34 000 dollars to 88 000 dollars (2002 U.S. dollars) per life-year gained, compared with stopping screening at age 65 years. Two studies suggested that it was more cost-effective to target healthy women than those with several competing risks for death. CONCLUSIONS: Current estimates suggest that biennial breast cancer screening after age 65 years reduces mortality at reasonable costs for women without clinically significant comorbid conditions. More data are needed on disease biology and preferences for benefits and harms in older women.

Age Factors↗

PubMed2003

Comparative efficacy and safety of long-acting oral opioids for chronic non-cancer pain: a systematic review.

Opioids have been endorsed as appropriate treatment for refractory chronic non-cancer pain when used according to published guidelines. They are widely used for this indication. However, there appear to be gaps in our understanding of the efficacy and safety of individual long-acting opioids compared to each other or as a class compared to short-acting opioids. This systematic review summarizes and assesses the evidence for the comparative efficacy and safety of long-acting opioids in the management of chronic non-cancer pain. Randomized trials (for comparative efficacy and adverse events) and observational studies (for adverse events only) that included non-parenteral long-acting opioids were sought using electronic databases, handsearching reference lists, and soliciting pharmaceutical company submissions. Searches were performed through October 2002. The validity of each included study was assessed using a data abstraction form and predefined criteria. An overall grade was allocated for the body of evidence for each key question. A total of 16 randomized trials (comparative efficacy and adverse events), enrolling 1427 patients, and 8 observational studies (adverse events) of 1190 patients were included in this review. No randomized trial was rated good quality; observational studies were generally of poorer quality than the trials. There was insufficient evidence to prove that different long-acting opioids are associated with different efficacy or safety profiles. There was also insufficient evidence to determine whether long-acting opioids as a class are more effective or safer than short-acting opioids. A subgroup of three studies on long-acting versus short-acting oxycodone was more homogeneous and provided fair evidence that these formulations are equally effective for pain control.

Analgesics, Opioid↗