Cryptococcal meningitis accounts for 15% of AIDS-related mortality. Cryptococcal antigen (CrAg) is detected in blood weeks before onset of meningitis, and CrAg positivity is an independent predictor ...of meningitis and death. CrAg screening for patients with advanced HIV and preemptive treatment is recommended by the World Health Organization, though implementation remains limited. Our objective was to evaluate costs and mortality reduction (lives saved) from a national CrAg screening program across Uganda.
We created a decision analytic model to evaluate CrAg screening. CrAg screening was considered for those with a CD4<100 cells/μL per national and international guidelines, and in the context of a national HIV test-and-treat program where CD4 testing was not available. Costs (2016 USD) were estimated for screening, preemptive therapy, hospitalization, and maintenance therapy. Parameter assumptions were based on large prospective CrAg screening studies in Uganda, and clinical trials from sub Saharan Africa. CrAg positive (CrAg+) persons could be: (a) asymptomatic and thus eligible for preemptive treatment with fluconazole; or (b) symptomatic with meningitis with hospitalization.
In the base case model for 1 million persons with a CD4 test annually, 128,000 with a CD4<100 cells/μL were screened, and 8,233 were asymptomatic CrAg+ and received preemptive therapy. Compared to no screening and treatment, CrAg screening and treatment in the base case cost $3,356,724 compared to doing nothing, and saved 7,320 lives, for a cost of $459 per life saved, with the $3.3 million in cost savings derived from fewer patients developing fulminant meningitis. In the scenario of a national HIV test-and-treat program, of 1 million HIV-infected persons, 800,000 persons were screened, of whom 640,000 returned to clinic, and 8,233 were incident CrAg positive (CrAg prevalence 1.4%). The total cost of a CrAg screening and treatment program was $4.16 million dollars, with 2,180 known deaths. Conversely, without CrAg screening, the cost of treating meningitis was $3.09 million dollars with 3,806 deaths. Thus, despite the very low CrAg prevalence of 1.4% in the general HIV-infected population, and inadequate retention-in-care, CrAg screening averted 43% of deaths from cryptococcal meningitis at a cost of $662 per death averted.
CrAg screening and treatment programs are cost-saving and lifesaving, assuming preemptive treatment is 77% effective in preventing death, and could be adopted and implemented by ministries of health to reduce mortality in those with advanced HIV disease. Even within HIV test-and-treat programs where CD4 testing is not performed, and CrAg prevalence is only 1.4%, CrAg screening is cost-effective.
AbstractObjectiveTo examine the accuracy of artificial intelligence (AI) for the detection of breast cancer in mammography screening practice.DesignSystematic review of test accuracy studies.Data ...sourcesMedline, Embase, Web of Science, and Cochrane Database of Systematic Reviews from 1 January 2010 to 17 May 2021.Eligibility criteriaStudies reporting test accuracy of AI algorithms, alone or in combination with radiologists, to detect cancer in women’s digital mammograms in screening practice, or in test sets. Reference standard was biopsy with histology or follow-up (for screen negative women). Outcomes included test accuracy and cancer type detected.Study selection and synthesisTwo reviewers independently assessed articles for inclusion and assessed the methodological quality of included studies using the QUality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. A single reviewer extracted data, which were checked by a second reviewer. Narrative data synthesis was performed.ResultsTwelve studies totalling 131 822 screened women were included. No prospective studies measuring test accuracy of AI in screening practice were found. Studies were of poor methodological quality. Three retrospective studies compared AI systems with the clinical decisions of the original radiologist, including 79 910 women, of whom 1878 had screen detected cancer or interval cancer within 12 months of screening. Thirty four (94%) of 36 AI systems evaluated in these studies were less accurate than a single radiologist, and all were less accurate than consensus of two or more radiologists. Five smaller studies (1086 women, 520 cancers) at high risk of bias and low generalisability to the clinical context reported that all five evaluated AI systems (as standalone to replace radiologist or as a reader aid) were more accurate than a single radiologist reading a test set in the laboratory. In three studies, AI used for triage screened out 53%, 45%, and 50% of women at low risk but also 10%, 4%, and 0% of cancers detected by radiologists.ConclusionsCurrent evidence for AI does not yet allow judgement of its accuracy in breast cancer screening programmes, and it is unclear where on the clinical pathway AI might be of most benefit. AI systems are not sufficiently specific to replace radiologist double reading in screening programmes. Promising results in smaller studies are not replicated in larger studies. Prospective studies are required to measure the effect of AI in clinical practice. Such studies will require clear stopping rules to ensure that AI does not reduce programme specificity.Study registrationProtocol registered as PROSPERO CRD42020213590.
AbstractObjectiveTo estimate benefits and harms of different colorectal cancer screening strategies, stratified by (baseline) 15-year colorectal cancer risk.DesignMicrosimulation modelling study ...using MIcrosimulation SCreening ANalysis-Colon (MISCAN-Colon).SettingA parallel guideline committee (BMJ Rapid Recommendations) defined the time frame and screening interventions, including selection of outcome measures.PopulationNorwegian men and women aged 50-79 years with varying 15-year colorectal cancer risk (1-7%).ComparisonsFour screening strategies were compared with no screening: biennial or annual faecal immunochemical test (FIT) or single sigmoidoscopy or colonoscopy at 100% adherence.Main outcome measuresColorectal cancer mortality and incidence, burdens, and harms over 15 years of follow-up. The certainty of the evidence was assessed using the GRADE approach.ResultsOver 15 years of follow-up, screening individuals aged 50-79 at 3% risk of colorectal cancer with annual FIT or single colonoscopy reduced colorectal cancer mortality by 6 per 1000 individuals. Single sigmoidoscopy and biennial FIT reduced it by 5 per 1000 individuals. Colonoscopy, sigmoidoscopy, and annual FIT reduced colorectal cancer incidence by 10, 8, and 4 per 1000 individuals, respectively. The estimated incidence reduction for biennial FIT was 1 per 1000 individuals. Serious harms were estimated to be between 3 per 1000 (biennial FIT) and 5 per 1000 individuals (colonoscopy); harms increased with older age. The absolute benefits of screening increased with increasing colorectal cancer risk, while harms were less affected by baseline risk. Results were sensitive to the setting defined by the guideline panel. Because of uncertainty associated with modelling assumptions, we applied a GRADE rating of low certainty evidence to all estimates.ConclusionsOver a 15 year period, all screening strategies may reduce colorectal cancer mortality to a similar extent. Colonoscopy and sigmoidoscopy may also reduce colorectal cancer incidence, while FIT shows a smaller incidence reduction. Harms are rare and of similar magnitude for all screening strategies.
Worldwide, more than one million people die each year from hepatitis C virus (HCV) related diseases, and over 300 million people are chronically infected with hepatitis B or C. Egypt used to be on ...the top of the countries with heavy HCV burden. Some countries are making advances in elimination of HCV, yet multiple factors preventing progress; remain for the majority. These factors include lack of global funding sources for treatment, late diagnosis, poor data, and inadequate screening. Treatment of HCV in Egypt has become one of the top national priorities since 2007. Egypt started a national treatment program intending to provide cure for Egyptian HCV-infected patients. Mass HCV treatment program had started using Pegylated interferon and ribavirin between 2007 and 2014. Yet, with the development of highly-effective direct acting antivirals (DAAs) for HCV, elimination of viral hepatitis has become a real possibility. The Egyptian National Committee for the Control of Viral Hepatitis did its best to provide Egyptian HCV patients with DAAs. Egypt adopted a strategy that represents a model of care that could help other countries with high HCV prevalence rate in their battle against HCV. This review covers the effects of HCV management in Egyptian real life settings and the outcome of different treatment protocols. Also, it deals with the current and future strategies for HCV prevention and screening as well as the challenges facing HCV elimination and the prospect of future eradication of HCV.
Update of the 2002 U.S. Preventive Services Task Force (USPSTF) recommendation statement on screening for colorectal cancer.
To update its recommendation, the USPSTF commissioned 2 studies: 1) a ...targeted systematic evidence review on 4 selected questions relating to test characteristics and benefits and harms of screening technologies, and 2) a decision analytic modeling analysis using population modeling techniques to compare the expected health outcomes and resource requirements of available screening modalities when used in a programmatic way over time.
The USPSTF recommends screening for colorectal cancer using fecal occult blood testing, sigmoidoscopy, or colonoscopy in adults, beginning at age 50 years and continuing until age 75 years. The risks and benefits of these screening methods vary. (A recommendation). The USPSTF recommends against routine screening for colorectal cancer in adults 76 to 85 years of age. There may be considerations that support colorectal cancer screening in an individual patient. (C recommendation). The USPSTF recommends against screening for colorectal cancer in adults older than age 85 years. (D recommendation). The USPSTF concludes that the evidence is insufficient to assess the benefits and harms of computed tomographic colonography and fecal DNA testing as screening modalities for colorectal cancer. (I statement).
Introduction Leading professional organizations recommend cervical cancer screening for average-risk women aged 21–65 years. For average-risk women aged >65 years, routine screening may be ...discontinued if “adequate” screening with negative results is documented. Screening is recommended after age 65 years for women who do not meet adequate prior screening criteria or are at special risk. Methods Authors examined the most recent cervical cancer incidence data from two federal cancer surveillance programs for all women by age and race, corrected for hysterectomy status. The 2013 and 2015 National Health Interview Surveys were analyzed in 2016 to examine the proportion of women aged 41–70 years without a hysterectomy who reported that they never had a Pap test or that their most recent Pap test was >5 years ago (not recently screened). Results The incidence rate for cervical cancer among older women, corrected for hysterectomy status, did not decline until age ≥85 years. The proportion not recently screened increased with age, from 12.1% for women aged 41–45 years to 18.4% for women aged 61–65 years. Conclusions Even among women within the recommended age range for routine screening, many are not up to date, and a substantial number of women approach the “stopping” age for cervical cancer screening without an adequate prior screening history. Efforts are needed to reach women who have not been adequately screened, including women aged >65 years, to prevent invasive cervical cancer cases and deaths among older women.
Atrial fibrillation (AF) is a common cardiac arrhythmia that increases the risk of thromboembolic events. Anticoagulation therapy to prevent AF-related stroke has been shown to be cost-effective. A ...national screening programme for AF may prevent AF-related events, but would involve a substantial investment of NHS resources.
To conduct a systematic review of the diagnostic test accuracy (DTA) of screening tests for AF, update a systematic review of comparative studies evaluating screening strategies for AF, develop an economic model to compare the cost-effectiveness of different screening strategies and review observational studies of AF screening to provide inputs to the model.
Systematic review, meta-analysis and cost-effectiveness analysis.
Primary care.
Adults.
Screening strategies, defined by screening test, age at initial and final screens, screening interval and format of screening {systematic opportunistic screening individuals offered screening if they consult with their general practitioner (GP) or systematic population screening (when all eligible individuals are invited to screening)}.
Sensitivity, specificity and diagnostic odds ratios; the odds ratio of detecting new AF cases compared with no screening; and the mean incremental net benefit compared with no screening.
Two reviewers screened the search results, extracted data and assessed the risk of bias. A DTA meta-analysis was perfomed, and a decision tree and Markov model was used to evaluate the cost-effectiveness of the screening strategies.
Diagnostic test accuracy depended on the screening test and how it was interpreted. In general, the screening tests identified in our review had high sensitivity (> 0.9). Systematic population and systematic opportunistic screening strategies were found to be similarly effective, with an estimated 170 individuals needed to be screened to detect one additional AF case compared with no screening. Systematic opportunistic screening was more likely to be cost-effective than systematic population screening, as long as the uptake of opportunistic screening observed in randomised controlled trials translates to practice. Modified blood pressure monitors, photoplethysmography or nurse pulse palpation were more likely to be cost-effective than other screening tests. A screening strategy with an initial screening age of 65 years and repeated screens every 5 years until age 80 years was likely to be cost-effective, provided that compliance with treatment does not decline with increasing age.
A national screening programme for AF is likely to represent a cost-effective use of resources. Systematic opportunistic screening is more likely to be cost-effective than systematic population screening. Nurse pulse palpation or modified blood pressure monitors would be appropriate screening tests, with confirmation by diagnostic 12-lead electrocardiography interpreted by a trained GP, with referral to a specialist in the case of an unclear diagnosis. Implementation strategies to operationalise uptake of systematic opportunistic screening in primary care should accompany any screening recommendations.
Many inputs for the economic model relied on a single trial the Screening for Atrial Fibrillation in the Elderly (SAFE) study and DTA results were based on a few studies at high risk of bias/of low applicability.
Comparative studies measuring long-term outcomes of screening strategies and DTA studies for new, emerging technologies and to replicate the results for photoplethysmography and GP interpretation of 12-lead electrocardiography in a screening population.
This study is registered as PROSPERO CRD42014013739.
The National Institute for Health Research Health Technology Assessment programme.
Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for ...Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on quality assurance in endoscopy includes 50 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of endoscopy and other elements in the screening process, including multidisciplinary diagnosis and management of the disease.
In 2016, the Japanese government decided to introduce endoscopic screening for gastric cancer as a national program. To provide endoscopic screening nationwide, we estimated the proportion of ...increase in the number of endoscopic examinations with the introduction of endoscopic screening, based on a national survey. The total number of endoscopic examinations has increased, particularly in clinics. Based on the national survey, the total number of participants in gastric cancer screening was 3 784 967. If 30% of the participants are switched from radiographic screening to endoscopic screening, approximately 1 million additional endoscopic examinations are needed. In Japan, the participation rates in gastric cancer screening and the number of hospitals and clinics offering upper gastrointestinal endoscopy vary among the 47 prefectures. If the participation rates are high and the numbers of hospitals and clinics are small, the proportion of increase becomes larger. Based on the same assumption, 50% of big cities can provide endoscopic screening with a 5% increase in the total number of endoscopic examinations. However, 16.7% of the medical districts are available for endoscopic screening within a 5% increase in the total number of endoscopic examinations. Despite the Japanese government's decision to introduce endoscopic screening for gastric cancer nationwide, its immediate introduction remains difficult because of insufficient medical resources in rural areas. This implies that endoscopic screening will be initially introduced to big cities. To promote endoscopic screening for gastric cancer nationwide, the disparity of medical resources must first be resolved.
Although the Japanese government has decided to introduce endoscopic screening for gastric cancer nationwide, its rapid introduction remains hindered by the insufficient medical resources in rural areas. Thus, endoscopic screening will likely and initially be introduced to big cities. This implies a disparity of medical resources that must be initially resolved to realize a smooth, nationwide implementation of endoscopic screening for gastric cancer.
Cancer screening is one approach to reducing cancer-related morbidity and mortality rates. Screening strategies vary in intensity. Higher-intensity strategies are not necessarily higher value. ...High-value strategies provide a degree of benefits that clearly justifies the harms and costs incurred; low-value screening provides limited or no benefits to justify the harms and costs. When cancer screening leads to benefits, an optimal intensity of screening maximizes value. Some aspects of screening practices, especially overuse and underuse, are low value.
Screening strategies for asymptomatic, average-risk adults for 5 common types of cancer were evaluated by reviewing clinical guidelines and evidence syntheses from the American College of Physicians (ACP), U.S. Preventive Services Task Force, American Academy of Family Physicians, American Cancer Society, American Congress of Obstetricians and Gynecologists, American Gastroenterological Association, and American Urological Association. "High value" was defined as the lowest screening intensity threshold at which organizations agree about screening recommendations for each type of cancer and "low value" as agreement about not recommending overly intensive screening strategies. This information is supplemented with additional findings from randomized, controlled trials; modeling studies; and studies of costs or resource use, including information found in the National Cancer Institute's Physician Data Query and UpToDate. The ACP provides high-value care screening advice for 5 common types of cancer; the specifics are outlined in this article. The ACP strongly encourages clinicians to adopt a cancer screening strategy that focuses on reaching all eligible persons with these high-value screening options while reducing overly intensive, low-value screening.
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