Trade-off between benefit and harm is crucial in health screening recommendations. Part I: general principles

Health screening is defined as the use of a test or a series of tests to detect unrecognized health risks or preclinical disease in apparently healthy populations to permit prevention and timely intervention. A health screening strategy consists of the sequence of a screening test, confirmatory test(s), and finally, treatment(s) for the condition detected. The potential benefits of health screening are easy to understand, but the huge potential for physical and psychological harm is less well recognized. Thus, health screening should only be recommended when five criteria are satisfied: (1) the burden of illness should be high, (2) the tests for screening and confirmation should be accurate, (3) early treatment (or prevention) must be more effective than late treatment, (4) the test(s) and treatment(s) must be safe, and (5) the cost of the screening strategy must be commensurate with potential benefit. Direct evidence from screening trials is subject to less bias. In some instances, indirect evidence may be acceptable, e.g., when the condition screened for is a risk factor for a disease rather than the disease itself.     

Chronic kidney disease: a public health problem that needs a public health action plan

For a health problem or condition to be considered a public health issue, four criteria must be met: 1) the health condition must place a large burden on society, a burden that is getting larger despite existing control efforts; 2) the burden must be distributed unfairly (i.e., certain segments of the population are unequally affected); 3) there must be evidence that upstream preventive strategies could substantially reduce the burden of the condition; and 4) such preventive strategies are not yet in place. Chronic kidney disease meets these criteria for a public health issue. Therefore, as a complement to clinical approaches to controlling it, a broad and coordinated public health approach will be necessary to meet the burgeoning health, economic, and societal challenges of chronic kidney disease.     

PEER REVIEWED: Chronic Kidney Disease: A Public Health Problem That Needs a Public Health Action Plan

For a health problem or condition to be considered a public health issue, four criteria must be met: 1) the health condition must place a large burden on society, a burden that is getting larger despite existing control efforts; 2) the burden must be distributed unfairly (i.e., certain segments of the population are unequally affected); 3) there must be evidence that upstream preventive strategies could substantially reduce the burden of the condition; and 4) such preventive strategies are not yet in place. Chronic kidney disease meets these criteria for a public health issue. Therefore, as a complement to clinical approaches to controlling it, a broad and coordinated public health approach will be necessary to meet the burgeoning health, economic, and societal challenges of chronic kidney disease.     

上海市新生儿疾病筛查成本效益分析

1方法本课题的研究模型根据新生儿筛查结果、病史抽样、文献资料和国家发表的经济统计数据进行。PKU和CH发病率根据1981年至lop7年上海市105．l万新生儿筛查调查,PKU发病率为1／17刀7,m发病率1／5用人1．l新生儿筛查成本新生儿筛查直接成本包括：材料、设备、劳务、组织管理、质量控制、医生和技术人员工资等。根据上述原则和实验规模,本文以上海市卫生行政部门制定的收费标准为标准（lop7年）,PKU6元,ThH30元,两项疾病筛查合计收费36元／人计算。疾病确诊和诊治费用：包括接诊挂号、化验、治疗费用。PKU用国产低苯丙酮酸奶方…     

Illness representations and coping following an abnormal colorectal cancer screening result

Receipt of an abnormal screening test result is likely to activate an illness representation that guides emotional, cognitive and behavioural responses. The study investigates relationships between illness representations specified by self-regulation theory, and coping responses in people receiving abnormal faecal occult blood test (FOBT) screening results during the UK colorectal cancer screening pilot. After completion of all clinical investigations and treatment, men and women diagnosed with invasive cancer (N=196), adenoma (N=208), or no neoplasia (N=293) completed measures of illness representations, coping and state anxiety. Gender, socioeconomic status and diagnosis explained significant variance in different coping strategies while illness representations contributed between 5% and 21% additional explained variance. While identity, causal attributions and emotional representations explained variance in the use of avoidance and distancing, perceived personal control was important in explaining efforts to make health behavioural changes following an abnormal result. Relatively more use of escape-avoidance coping following a first abnormal screen was significantly associated with non-participation in screening 2 years later.     

Using Decision-Analytic Modeling to Isolate Interventions That Are Feasible,Efficient and Optimal: An Application from the Norwegian Cervical Cancer Screening Program

BackgroundDecision makers often need to simultaneously consider multiple criteria or outcomes when deciding whether to adopt new health interventions.ObjectivesUsing decision analysis within the context of cervical cancer screening in Norway, we aimed to aid decision makers in identifying a subset of relevant strategies that are simultaneously efficient, feasible, and optimal.MethodsWe developed an age-stratified probabilistic decision tree model following a cohort of women attending primary screening through one screening round. We enumerated detected precancers (i.e., cervical intraepithelial neoplasia of grade 2 or more severe (CIN2+)), colposcopies performed, and monetary costs associated with 10 alternative triage algorithms for women with abnormal cytology results. As efficiency metrics, we calculated incremental cost-effectiveness, and harm-benefit, ratios, defined as the additional costs, or the additional number of colposcopies, per additional CIN2+ detected. We estimated capacity requirements and uncertainty surrounding which strategy is optimal according to the decision rule, involving willingness to pay (monetary or resources consumed per added benefit).ResultsFor ages 25 to 33 years, we eliminated four strategies that did not fall on either efficiency frontier, while one strategy was efficient with respect to both efficiency metrics. Compared with current practice in Norway, two strategies detected more precancers at lower monetary costs, but some required more colposcopies. Similar results were found for women aged 34 to 69 years.ConclusionsImproving the effectiveness and efficiency of cervical cancer screening may necessitate additional resources. Although efficient and feasible, both society and individuals must specify their willingness to accept the additional resources and perceived harms required to increase effectiveness before a strategy can be considered optimal.     

HIV抗体筛查阳性标本的确证结果分析

目的通过对HIV抗体筛查(ELISA)阳性标本进行确证试验(WB),分析两者之间的关系;了解不确定结果的抗体进展情况。方法按照《全国艾滋病检测技术规范》(2009版)的方法和要求,对284例HIV抗体筛查(ELISA)阳性标本采用WB进行确证,对确证结果不确定者进行随访复查。结果 284例(ELISA)阳性标本中,228例确证(WB)HIV阳性、41例不确定、15例阴性。41例不确定经后续复查25例进展为确证阳性、其中20例在四周内进展为阳性。结论 s/co值>6.0以上的阳性标本,确证阳性率明显增高;不确定结果的复查可根据受检者的高危行为提前进行。     

68例抗-HIV1/2初筛阳性儿童确证结果分析

目的了解抗-HIV1/2初筛试验阳性儿童确证试验的情况及导致抗-HIV1/2初筛试验假阳性的原因。方法对快速免疫胶体金试条和ELISA抗-HIV1/2初筛阳性的标本送北京市疾控中心采用免疫印迹法进行确证,分析确证试验阳性、可疑及阴性患儿所占比例及患儿的性别、临床诊断及初筛试验S/CO值。结果4例快速免疫胶体金试条初筛阳性患儿经确证均为抗-HIV1阳性,在64例ELISA初筛阳性患儿中,经确证抗-HIV1阳性24例(37.50%),可疑3例(4.69%),阴性37例(57.81%);3组S/CO值分别为8.46±0.19;2.46±0.52和2.57±1.33,阳性组S/CO值与阴性组相比,差异具有统计学意义(P0.01);确证阳性组患儿入院诊断有发热、上呼吸道感染、肺炎、鹅口疮、腹泻及血栓性血小板减少性紫癜等。结论酶联免疫法初筛儿科患者抗-HIV1/2具有一定的假阳性率;某些儿科疾病可导致抗-HIV1/2初筛试验假阳性。     

Rethinking Immigrant Tuberculosis Control in Canada: From Medical Surveillance to Tackling Social Determinants of Health

Current tuberculosis control strategies in Canada rely exclusively on screening and surveillance of immigrants. This is consistent with current public health discourse that attributes the high burden of immigrant tuberculosis to the exposure of immigrants to infection in their country of origin. The effectiveness of control strategies is questionable given the evidence that many immigrants are at higher risk of tuberculosis reactivation because of risk factors such as poverty, malnutrition and overcrowded housing. This paper argues that the absence of policies that address poverty-related disadvantages among immigrants makes these populations more vulnerable to the reactivation of their tuberculosis long after they have been exposed in their countries of birth. Policies for tuberculosis prevention in the Aboriginal population attend to their poverty and other social determinants of health. Effective health prevention policy for tuberculosis within the immigrant population must take similar direction.     

Health benefits,safety and cost of physical activity interventions for mental health conditions: A meta-review to inform translation efforts

BackgroundMental illness is a leading cause of the global burden of disease. Physical activity (PA) can improve physical and mental health outcomes for people with mental illness, yet routine implementation of PA within standard care remains ad-hoc. The reasons for this are unclear, although the dissonance between the evidence produced in research settings and that needed in real-world environments may be key.PurposeTo explore the effectiveness of PA interventions as a treatment for mental illness. We synthesised past systematic reviews and meta-analyses.MethodsWe conducted a systematic review of reviews from database inception to 09/2017. Reviews were included that considered any mental health condition (diagnosed via standardised criteria) and where PA interventions were a stand-alone or adjunctive treatment. Effectiveness was defined as outcomes that are important in real-world healthcare (i.e. expected clinical outcomes, intervention safety and cost).ResultsFrom 4008 hits, 33 reviews (including 155 unique studies) were included and 32 reported that PA has a positive effect on at least one main outcome of interest (symptoms of mental illness, quality of life and/or physical health). There was inconsistent reporting of adverse events and no cost data was identified. The AMSTAR quality rating suggests inconsistencies in review quality.ConclusionsThe research agenda must expand to report on outcomes that can support evidence translation efforts (i.e. cost and adverse events). Without such a shift, research in PA and mental health may fail to achieve translation to routine care and may have limited impact on patient outcomes.     

Screening in Austria: the cases of mammography, PSA testing, and routine use of ultrasound in pregnancy

OBJECTIVE: To study cases of screening in Austria to learn about national strategies to handle the health policy challenge of early detection of widespread diseases and about the outcome of those strategies. The article describes three healthcare interventions (mammography, PSA testing, and routine use of ultrasound in pregnancy) and the instruments of Austrian health policy that are used-with or without explicit intention-to enforce or to control the widespread use of (early) diagnoses. METHODS: Data and information collection on healthcare services, their accessibility, rate of use, expert consensus, and official regulations. For all three case studies, expert interviews were carried out with main actors. RESULTS: Risk-group screening is not a priority in Austrian federal health policy. Although health promotion and prevention is a national task, examinations for early detection of specific diseases (i.e., carcinoma) are left to the health insurance funds, which delegate the decision to offer early diagnoses to their contracted physicians. In this opportunistic screening, general practitioners or specialists are encouraged by their health insurance funds or motivated by professional guidelines to offer certain examinations. CONCLUSIONS: Screening is a coordinated effort to acquire a grasp of a common disease at an early stage in a specified population. To achieve this objective, a culture of coordination and centralization has to be implemented. The collection of data is an essential element in coordination of decentralized medical interventions as much as quality control is an essential task in looking at and comparing the outcome of interventions. In the three case studies, neither of these two essential criteria were met. Evaluations and scientific evidence on the effectiveness of interventions were not used.     

Secondary prevention of cancer: an overview

Secondary prevention of cancer (screening) involves the use of tests to detect a cancer before the appearance of signs or symptoms. Before starting such a programme, the available evidence should be analysed to estimate the effectiveness of the proposed activities. Essential requirements are an understanding of the natural history of the particular cancer, availability of a test that can detect it, effective treatment for it, good evidence that early detection reduces the incidence and/or mortality, and that the expected benefits of screening outweigh the risks and costs. A screening programme should be limited to significant cancers and applied selectively, and should be integrated into the total health care programme. Programmes should take into account the risks, costs and expected benefits; provide quality assurance as well as facilities to follow, diagnose, and treat people with positive test results; maintain all records; and keep costs to a minimum. Ideally the effectiveness of screening should be demonstrated by randomized controlled trials showing a reduction in mortality, but this type of evidence exists for few cancers. Often an estimate of the effectiveness of screening must rest on other types of evidence, such as observations that the tests can detect the cancer before the appearance of signs or symptoms; that the tests can find a greater proportion of cancers in early stages; and that the patients with cancers detected through screening have higher survival rates after diagnosis and treatment although it must be recognized that these observations may be biased. This article discusses the available evidence on the effectiveness of screening for eight cancers, and gives estimates of the potential impact of secondary prevention for the year 2000.     

The illness burden of alcohol-related disorders among VA patients: the veterans health study

Little is known about the illness burden associated with alcohol-related disorders (ie, problem drinking, alcohol abuse, and alcohol dependence) among patients in outpatient medical care. The objective of this study was to examine several aspects of illness burden-medical comorbidities, patterns of health services use, and functional status-among Veterans Health Administration (VA) ambulatory care patients with alcohol-related disorders. Male participants (N = 2425) were recruited at 1 of 4 Boston-area VA outpatient clinics. They completed self-report screening measures of current alcohol-related disorders (CAGE score > or =2 with past year alcohol consumption), health behaviors, medical comorbidities, and functional status (SF-36). A medical history interview, which assessed comorbid conditions and use of recent health services, was also administered. Screening criteria for current alcohol-related disorders were satisfied by 12%; however, only 40% of these reported ever receiving treatment specifically for alcohol-related disorders. Patients who screened positive for alcohol-related disorders reported significantly greater limitations in mental health function, longer hospitalizations for medical care in the prior year, and fewer outpatient medical visits in the previous 3 months. Findings suggest considerable illness burden associated with alcohol-related disorders among VA ambulatory care patients. Efforts to increase detection and treatment of alcohol-related disorders may lessen the illness burden and cost of alcohol-related disorders.     

Using State Lead Poisoning Surveillance System Data to Assess False Positive Results of Capillary Testing

Objective: The purpose of this study was to determine the false positive percentage of capillary blood lead screening in a statewide surveillance system and to explore potential predictors of false positive results. Methods: Data were all blood lead tests of 0–5 year old children in Maine during 2002–2003. We determined the proportion of children with elevated (≥10 μg/dL) capillary test results who received a venous confirmatory test, and calculated the percentage of false positive tests, defined as a capillary test of ≥10 μg/dL with a confirmatory venous test of <10 μg/dL. Multivariable binomial regression was used to determine whether capillary blood lead level and length of time between capillary and venous tests predicted false positive results, after controlling for potential confounders. We also examined the positive bias of the capillary test among both false positive and true positive results. Results: Seventy-three percent of elevated capillary screening tests (2.2 percent of all capillary screening tests) were false positives. False positive results were less likely for capillary levels of 15–19 μg/dL (RR=0.78; 95% CI 0.5–0.92) and 20 μg/dL or above (RR=0.83; 95% CI 0.71–0.96) compared to 10–14 μg/dL. The percentage of false positives did not vary by interval between screening and confirmatory tests. The capillary test exhibited a positive bias compared to the venous test, even among true positive results. Conclusions: False positive results may have been caused by sample contamination, rather than laboratory error or true variation in blood lead level between screening and confirmatory tests. Capillary screening could be improved by training in proper sample collection methods.     

Cancer screening and early diagnosis in low and middle income countries

Limited health system capacities and competing health priorities in low and middle income countries (LMICs) necessitate a pragmatic approach to population-based cancer screening. Thus, the challenges faced by LMICs to implement a ‘western’ model of screening for common cancers and the possible means to overcome these challenges are presented. Breast cancer is the number one cancer with a rising trend in the majority of LMICs. Implementation of mass-scale mammography-based screening is not feasible and sustainable in most of them. While some LMICs have introduced breast cancer screening based on clinical breast examination (CBE), the programs need to be of appropriate quality. All LMICs should improve the capacity for early diagnosis of breast cancer along with other common cancers through community education, training of frontline health workers, facilitating prompt referrals and improving the infrastructure for cancer diagnosis and treatment. Resources permitting, the LMICs with high burden of cervical cancer may consider human papillomavirus (HPV) detection-based screening; a simple low-cost alternative is visual inspection with acetic acid (VIA). Regardless of the choice, a strong linkage should be established between screening and treatment with implementation of robust quality assurance. The few LMICs with a rising trend of colorectal cancers and adequate resources may implement demonstration projects to screen with fecal immunochemical tests (FIT). Oral cancer screening of habitual tobacco and/or alcohol users using oral visual examination (OVE) may be implemented in countries with high burden of the cancer, but primary prevention (i.e., tobacco/alcohol cessation) should be prioritized. Screenings for other cancers are not recommended for LMICs.     

Preventive health care among older women in an academic primary care practice.

PURPOSE: We sought to examine the use of preventive health services among older women and to assess how age and illness burden influence care patterns. METHODS: The charts of 299 women aged > or =80 and 229 women aged 65-79 years who did not have dementia or terminal illness at 1 academic primary care practice in Boston were reviewed between July and December 2005 to determine receipt of screening tests (e.g., mammography), counseling on healthy lifestyle (e.g., exercise), and/or geriatric health issues (e.g., incontinence), and immunizations. Illness burden was quantified using the Charlson Comorbidity Index (CCI). RESULTS: Women aged > or =80 were more likely than women aged 65-79 to have a CCI of > or =3 (24.0% vs. 16.7%) and were less likely to receive all screening tests. However, receipt of mammography (47.8%) and colon cancer screening (51.2%) was still common among women aged > or =80 and was not targeted to older women in good health. Women aged > or =80 were less likely to be screened for depression (adjusted relative risk [aRR] 0.6; 95% confidence interval [CI], 0.5-0.8), osteoporosis (aRR, 0.6; 95% CI, 0.5-0.9), or counseled about exercise (aRR 0.8; 95% CI, 0.6-0.9) than younger women, but were more likely to receive counseling about falls (aRR 1.9; 95% CI, 1.4-2.6) and/or incontinence (aRR 1.8; 95% CI, 1.2-2.6). However notes documenting discussions about mood (28.6%), exercise (40.0%), falls (28.8%), or incontinence (20.8%) were low among all women. CONCLUSION: In a comprehensive review of preventive health measures for elderly women, many in poor health were screened for cancer. Meanwhile, many older women were not screened for depression or counseled about exercise, falls, or incontinence. There is a need to improve delivery of preventive health care to older women.     

Health prioritization: the case of Chile

This paper examines the introduction of a prioritized list of fifty-six health conditions in Chile, for which access to treatment is guaranteed. This is an important health reform issue, and the discussion of Chile's rich and complex approach may benefit other countries. Conditions on the list were selected using multiple criteria: burden of disease, inequality, high costs, social preferences, rule of rescue, and cost-effectiveness. The dominant criteria were high burden of disease and social preferences. Cost-effectiveness was introduced after the fact to identify effective treatments at a cost that the country could afford.     

Effective teaching of communication skills for medical practice: selecting an appropriate clinical context

Increasingly, courses in communication skills are being incorporated into medical training. In order for communication skills to be effectively maintained in post-training medical practice, they must be taught within an appropriate clinical context. The present paper describes and provides rationale for seven criteria by which to select clinical issues which are appropriate foci for communication skills courses. The criteria are : (1) the issue must be one which is encountered frequently in clinical practice; (2) the issue must be associated with a high burden of illness; (3) there must be evidence that practitioners need to improve skills for dealing with the issue; (4) there must be an intervention, of which communication skills are an integral component, that is demonstrably effective for dealing with the clinical issue; (5) the intervention must represent a cost-effective means of dealing with the issue; (6) the intervention must be acceptable to doctors and be able to be incorporated into routine medical practice; (7) the intervention must be acceptable to patients. Examples of clinical issues which fit these criteria are given in the paper and include smoking, hazardous alcohol consumption, non-adherence to treatment instructions, overdue cervical screening, inappropriate diet, recovery from medical interventions, and breaking bad news to patients.     

Health technology assessment in the cost-disutility plane.

Previously, comparisons of multiple strategies in health technology assessment have been undertaken on the incremental cost-effectiveness plane using efficiency frontiers and cost-effectiveness acceptability curves. This article proposes shifting the comparison of multiple strategies to the cost-disutility plane. Evidence-based decision making requires comparison of all strategies against each other. Consequently, the origin in the incremental cost-effectiveness plane cannot be the appropriate reference point in comparing multiple nondominated strategies. A linear transformation onto the cost-disutility plane allows an equivalent comparison of net benefit and permits the use of standard efficiency measurement methods to estimate 1) the degree of dominance (technical inefficiency) of dominated strategies and 2) the net benefit inefficiency (i.e., losses in net benefit relative to an optimal strategy). In comparing strategies under uncertainty, a comparison of loss in net benefit leads to the expected net loss frontier, which, unlike cost effectiveness acceptability curves, directly identifies differences in expected net benefit (net loss) and the expected value of perfect information. Thus, decision makers can be better informed about the choice of optimal strategy and the potential value of future research to resolve uncertainty. Comparing strategies in the cost-disutility plane is suggested to better inform decision making and to provide a link between the cost-effectiveness literature and efficiency measurement methods.     

Public health consequences of a false-positive laboratory test result for Brucella--Florida, Georgia, and Michigan, 2005

Human brucellosis, a nationally notifiable disease, is uncommon in the United States. Most human cases have occurred in returned travelers or immigrants from regions where brucellosis is endemic, or were acquired domestically from eating illegally imported, unpasteurized fresh cheeses. In January 2005, a woman aged 35 years who lived in Nassau County, Florida, received a diagnosis of brucellosis, based on results of a Brucella immunoglobulin M (IgM) enzyme immunoassay (EIA) performed in a commercial laboratory using analyte specific reagents (ASRs); this diagnosis prompted an investigation of dairy products in two other states. Subsequent confirmatory antibody testing by Brucella microagglutination test (BMAT) performed at CDC on the patient's serum was negative. The case did not meet the CDC/Council of State and Territorial Epidemiologists' (CSTE) definition for a probable or confirmed brucellosis case, and the initial EIA result was determined to be a false positive. This report summarizes the case history, laboratory findings, and public health investigations. CDC recommends that Brucella serology testing only be performed using tests cleared or approved by the Food and Drug Administration (FDA) or validated under the Clinical Laboratory Improvement Amendments (CLIA) and shown to reliably detect the presence of Brucella infection. Results from these tests should be considered supportive evidence for recent infection only and interpreted in the context of a clinically compatible illness and exposure history. EIA is not considered a confirmatory Brucella antibody test; positive screening test results should be confirmed by Brucella-specific agglutination (i.e., BMAT or standard tube agglutination test) methods.