Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Screening”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,657 records · Page 92Linked to original sources
PubMed2000

Breast cancer screening; cost-effective in practice?

The main aim of national breast screening is a reduction in breast cancer mortality. The data on the reduction in breast cancer mortality from three (of the five) Swedish trials in particular gave rise to the expectation that the Dutch programme of 2-yearly screening for women aged 50-70 would produce a 16% reduction in the total population. In all likelihood, many of the years of life gained as a result of screening are enjoyed in good health. According to its critics the actual benefit that can be achieved from the national breast cancer screening programmes is overstated. Considerable benefits have recently been demonstrated in England and Wales. However, the fall was so considerable in such a relatively short space of time that screening (started in 1987) was thought to only have played a small part. As far as the Dutch screening programme is concerned it is still too early to reach any conclusions about a possible reduction in mortality. The first short-term results of the screening are favourable and as good as (or better than) expectations. In Swedish regions where mammographic screening was introduced, a 19% reduction in breast cancer mortality can be estimated at population level, and recently a 20% reduction was presented in the UK. In countries where women are expected to make appointments for screening themselves, the attendance figures are significantly lower and the quality of the process as a whole is sometimes poorer. The benefits of breast cancer screening need to be carefully balanced against the burden to women and to the health care system. Mass breast screening requires many resources and will be a costly service. Cost-effectiveness of a breast cancer screening programme can be estimated using a computer model. Published cost-effectiveness ratios may differ tremendously, but are often the result of different types of calculation, time periods considered, including or excluding downstream cost. The approach of simulation and estimation is here the same for all countries. The effects of a breast-screening program depend on many factors, such as the epidemiology of the disease, the health care system, costs of health care, the quality of the screening programme and the attendance rate. The estimated CE-ratio ranges from 2650 euros per life-year gained in Navarra to 9650 in Germany. Although relatively low incidence levels expected, the CE-ratio in Navarra is most favourable probably due to a relatively unfavourable clinical stage distribution before screening and the increasing incidence. The UK has a screening situation that is almost similar with the Netherlands. Therefore, the CE-ratios of both countries are comparable. The differences between countries make it impossible to set up one uniform screening policy. The theoretical outcomes of the benefit that can be achieved are generally from small-scale trials involving a limited number of experts, persons examined, and areas. On a national scale, with hundreds of professional practitioners, it can be expected to be more difficult to attain uniform quality. Continuous quality control, monitoring and evaluation are therefore crucial.

Aged↗
PubMed2001

Impediments to screening for hazardous alcohol use and dependence in general hospital psychiatric inpatients.

OBJECTIVE: The Alcohol Use Disorders Identification Test (AUDIT) has been developed to screen for hazardous and harmful alcohol consumption. It has been used among a variety of primary care, general population and general hospital populations. However, with the exception of one study undertaken by the author and colleagues, the use of the AUDIT in general hospital psychiatric patients has not been reported. This paper reports on a substudy of this larger study whose aim was to determine the frequency of hazardous alcohol use and dependence among patients admitted to the psychiatric units of general hospitals in Perth, Western Australia, and discusses major reasons for non-AUDIT screening among this group. METHOD: In a 12-month period 990 patients aged 18-64 years and residing in the Perth metropolitan area were admitted to the psychiatric unit of the two hospitals. Using the AUDIT alcohol use in patients with four major types of psychiatric disorder, namely mood, adjustment, anxiety and psychotic disorders, was assessed. RESULTS: Of the 834 admissions targeted for AUDIT screening 263 were not screened. This non-screening represented 27-42% of patients in each of the major diagnostic categories. There was no significant difference in the proportion of patients screened versus not screened for mood, adjustment or schizophrenia/psychosis. There were however, significantly fewer patients with anxiety disorder screened compared with mood disorder. Those non-screened patients in major psychiatric groups had significantly shorter hospital stays than their diagnostic counterparts who were screened. The major reason for non-screening in all groups was due to patients leaving the psychiatric facility before they could be accessed. This included discharge before screening, transfer to another psychiatric facility and short admission. To a lesser extent cognitive dysfunction accounted for non-screening among major diagnostic groups. CONCLUSIONS: Failure to screen patients was largely due to short hospital stays. Screening was impeded by the brief window period, commonly 1 or 2 days, between the absence of acute psychiatric sequelae and discharge. This situation contrasts dramatically to the medical or surgical admission where major sequelae are largely resolved in 2-3 days and AUDIT screening can take place over the remaining 3-4 days prior to discharge. To be effective in the general hospital psychiatric setting, alcohol screening needs to be incorporated into the routine ward assessment procedures. The brevity of the AUDIT makes this possible. This would maximize the time available to implement an intervention programme to those found to be consuming alcohol at a hazardous or harmful level.

Adolescent↗
PubMed2001

Early discharge of low-risk women from cervical screening.

BACKGROUND: The Scottish Cervical Screening Programme currently offers three-yearly screening to all women between the ages of 20 and 60. However, previous studies have indicated that well-screened women over the age of 50 are likely to be at low risk of cervical neoplasia. This study aimed to explore the implications of discharging these women from screening in a typical area of Scotland. METHODS: A case-control study of the screening histories of women with and without screen-detected cervical neoplasia between ages 50 and 59 in Lanarkshire was carried out, as well as a cross-sectional study of the prevalence of adequate screening histories among women currently aged 50 in Lanarkshire. Routine screening programme statistics were used to estimate the effects of introducing an early discharge policy. RESULTS: Women reaching the age of 50 with two recent, consecutive, negative smears had reduced odds of screen-detected neoplasia in the subsequent decade. The estimated odds ratio for all screen-detected neoplasia (CIN 1-3, adenocarcinoma in situ and invasive carcinoma) was 4.4 [95 per cent confidence interval (CI) 1.6-13.2, p = 0.002]. The estimated odds ratio for screen-detected high-grade CIN and invasive squamous carcinoma was 17.0 (95 per cent CI 2.4-243.0, p = 0.0004). A total of 54.0 per cent (95 per cent CI 47.9-59.9 per cent) of screening participants currently aged 50 fulfilled the definition of adequate screening. Discharging these women might be expected to reduce screening workload by approximately 10 per cent, but those discharged would be at increased risk of neoplasia. CONCLUSION: Now that full screening histories are available in all health board areas since 1990, the identification of a low-risk group within the screened population could be the first step towards a screening programme targeted more closely on those with the greatest capacity to benefit.

Case-Control Studies↗
PubMed1999

Serial prostate specific antigen screening for prostate cancer: a computer model evaluates competing strategies.

PURPOSE: We compare prostate specific antigen (PSA) screening strategies in terms of expected years of life saved with screening, number of screens, number of false-positive screens and rates of over diagnosis, defined as detection by PSA screening of patients who would never have been diagnosed without screening. MATERIALS AND METHODS: A computer model of disease progression, clinical diagnosis, PSA growth and PSA screening was used. Under baseline conditions, when screening is not considered, the model replicates clinical diagnosis and disease mortality rates recorded by the Surveillance, Epidemiology and End Results Program of the National Cancer Institute in the mid 1980s. RESULTS: Biannual screening with PSA greater than 4.0 ng./ml. was projected to reduce the number of screens and false-positive tests by almost 50% relative to annual screening while retaining 93% of years of life saved. With annual screening use of an age specific bound for PSA to consider a test positive instead of the standard 4.0 ng./ml. was projected to reduce false-positive screens by 27% and over diagnosis by a third while retaining almost 95% of years of life saved. Sensitivity analyses did not change the relative efficacy of biannual screening. CONCLUSIONS: Under the model assumptions biannual PSA screening is a cost-effective alternative to annual PSA screening for prostate cancer. With annual screening use of an age specific bound for PSA positivity appears to reduce false-positive results and over diagnosis rates sharply relative to a bound of 4 ng./ml. while retaining most of the survival benefits.

Adult↗
PubMed2004

The frequency of Pap smear screening in the United States.

BACKGROUND: U.S. professional medical societies and the national health systems of all other industrialized nations recommend that most women need not undergo Papanicolaou (Pap) smear screening annually. There are no data, however, regarding the frequency at which women actually undergo screening. OBJECTIVE: To describe the frequency of cervical cancer screening in the United States. DESIGN: National Health Interview Survey, a cross-sectional population-based telephone survey conducted by the National Center for Health Statistics. PARTICIPANTS: Representative sample of U.S. women age 21 and older who denied a history of cancer (N = 16,467). MEASUREMENTS: Pap smear screening frequency, categorized as no regular screening or screening at 1 of 3 discrete screening intervals (every year, every 2 years, or every 3 years) based on each woman's reported number of Pap smears in the previous 6 years. RESULTS: The vast majority (93%) of American women report having had at least one Pap smear in their lifetime. Among women with no history of abnormal smears, 55% undergo Pap smear screening annually, 17% report a 2-year screening interval, 16% report being screened every 3 years, and 11% are not being screened regularly. Even the very elderly report frequent screening-38% of women age 75 to 84 and 20% of women age 85 and older reported annual Pap smears. Overall, 20% of women reported having had at least one abnormal Pap smear. Among these women, rates of frequent Pap smear screening are considerably higher-80% undergo annual screening, with only a modest decline in screening frequency with increasing age. CONCLUSIONS: The majority of American women report being screened for cervical cancer more frequently than recommended. Lengthening the screening interval would not only reduce the volume of specimens that cytotechnologists are required to read, but would also reduce the follow-up testing after abnormal smears.

Adult↗
PubMed2000

Projecting mammographic screens.

OBJECTIVE: The purpose of mammographic screening is to reduce mortality from breast cancer. This study describes a method for projecting the number of screens to be performed by a mammographic screening programme, and applies this method in the context of New South Wales, Australia. METHOD: The total number of mammographic screens was projected as the sum of initial screens and re-screens, and is based on projections of the population, rates of new recruitment, rates of attrition within the programme, and the mix of screening intervals. The baseline scenario involved: 70% participation of women aged 50-69 years, 90% return rate for the second and subsequent re-screens, 5% annual screens (95% biennial screens), and a specified population projection. The results were assessed with respect to variations in these assumptions. RESULTS: The projections were strongly influenced by: the rate of screening of the target age group; the proportion of women re-screened annually; and the rates of attrition within the programme. Although demographic change had a notable effect, there was little difference between different population projections. Standard assumptions about attrition within the programme suggest that the current target participation rates in NSW may not be achieved in the long term. CONCLUSIONS: A practical model for projecting mammographic screens for populations is described which is capable of forecasting the number of screens under different scenarios. IMPLICATIONS: Projections of mammographic screens provide important information for the planning and financing of equipment and personnel, and for testing the effects of variations in important operational parameters. Re-screening attrition is an important contributor to screening viability.

Adult↗
PubMed2001

Results from 10 years of breast screening in Wales.

OBJECTIVE: To present results from 10 years of breast screening in Wales, including rates of interval cancers. SETTING: All women aged 50-64 years in Wales; approximately 250,000 in each screening round. METHODS: Breast Test Wales (BTW) began mammographic screening in 1989 as part of the National Breast Screening Programme. Two view mammography was introduced at the inception of the Welsh programme for all prevalent screens. Single view mammography was subsequently performed for incident screens. Interval cancers were identified by matching details from the BTW administrative screening database with the BTW database of all incident breast cancers for residents in Wales. RESULTS: For the first and second round prevalent screens, the cancer detection rate was 8.6 per 1000 and 7.4 per 1000 screened, respectively. The interval cancer rates following round one were 4.9 per 10,000 in the first 12 months, 9.0 per 10,000 between 12 and 24 months, and 11.6 per 10,000 between 24 and 36 months after screening. For the second round incident screens the detection rate was 4.6 per 1000 and the standardised detection ratio was 0.89, but the interval cancer rates in the first year after incident screens were not statistically different from those following prevalent screens. There was no change in the proportion of invasive breast cancers which were < 15 mm in diameter, or in the grades of invasive cancer between the first and second rounds, prevalent or incident screens. CONCLUSIONS: Breast Test Wales has achieved the standards set by the National Health Service Breast Screening Programme. Taking two views at the prevalent screen gave high sensitivity and may have resulted in the low standardised detection ratio at subsequent incident screens.

Breast Neoplasms↗
PubMedDate not supplied

Multicenter comparison of manual and automated screening of AutoCyte gynecologic preparations.

OBJECTIVE: To compare AutoCyte SCREEN-assisted evaluation of AutoCyte PREP liquid-based preparations with manual microscopic screening of the same preparations in a masked, multisite trial. STUDY DESIGN: AutoCyte PREPs were made using the CytoRich automated, liquidbased method from the residual cellular material on the collection device after a conventional cervical smear had been made. The study involved 1,676 samples collected sequentially from high-risk patients at two medical centers. The AutoCyte PREPs were then screened manually by cytotechnologists at one of two laboratory sites. All abnormal slides were reviewed by the site pathologists for final diagnosis. The PREPs were then remasked and screened using the AutoCyte SCREEN automated, interactive screening system, designed to select potentially abnormal slides for manual review while allowing the direct sign-out of negative slides. The AutoCyte SCREEN-assisted practice result was determined by combining the interactive SCREEN result with manual evaluation for those cases selected by SCREEN for manual review. All slides deemed abnormal were manually reviewed by an independent reference pathologist. The original manual review results were then compared to the AutoCyte SCREEN-assisted practice results stratified by the Bethesda categories of abnormal diagnoses as determined by the reference pathologist. RESULTS: Of the 1,676 cases, 494 were determined to be abnormal (ASCUS+) by one or both of the study methods and also by the independent reference pathologist. Of these 494 abnormal cases, 312 had a reference diagnosis of LSIL+, and 139 had a reference diagnosis of HSIL or cancer. The remainder of these cases were ASCUS or AGUS. Sensitivities and false negative proportions were stratified by the reference pathologist based on Bethesda categories as "truth" and compared. For LSIL+ cases, manual screening alone had a sensitivity of 89% as compared to 98% for the AutoCyte SCREEN-assisted practice. Manual screening demonstrated 90% sensitivity to HSIL or greater abnormality as compared to 99% sensitivity by the AutoCyte SCREEN-assisted practice. CONCLUSION: There was a concurrent significant reduction in the false negative fraction using the AutoCyte SCREEN as part of screening practice. Specificity for both screening practices was equivalent.

False Negative Reactions↗
PubMed2005

Psychosocial impact of screening for intracranial aneurysms in relatives with familial subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: In families with > or =2 relatives with intracranial aneurysms (IAs), screening for IAs in asymptomatic first-degree relatives is often recommended. We assessed the long-term psychosocial impact of such screening. METHODS: We identified all persons with IA (screen-positives) and matched them for age and sex with 2 controls without IA (screen-negatives) from hospital-based registers of familial IA. Persons underwent telephone interviews using questionnaires that covered the areas of psychosocial impact of screening, health-related quality of life (HRQoL), and mood. Data were compared between screen-positives and screen-negatives, and with reference populations. RESULTS: Overall, 105 persons from 33 families with IA were included, of whom 35 were screen-positive and 70 were screen-negative. Of the screen-positives, 12 (44%) had reduced their work and 23 (66%) had experienced changes in > or =1 area of independence, self-esteem, future outlook, or personal relationships. In contrast, only 1 (2%) screen-negative person had stopped working and 12 (17%) others had experienced changes in their self-esteem, future outlook, or relationships. Screen-positives had lower HRQoL compared with screen-negatives and the reference population, whereas both screen groups had higher mean depression scores than the reference population. Despite these effects, only 3 persons regretted participating in screening. CONCLUSIONS: Although screening for IA is an important preventative strategy in high-risk individuals, it is associated with considerable psychosocial effects, both positive and negative. Greater awareness of such outcomes, and appropriate intervention where necessary, would appear to be a necessary component of IA screening programs.

Adult↗
PubMed1994

Screening for melanoma and options for its evaluation [see comment].

A review of the published evidence presented here argues that screening for melanoma is recommended and practised at present, but with wide diversity of opinions about its value; there is evidence that screening has considerable potential for benefit, but the evidence of actual benefit is limited; and there are substantial costs and potential hazards from screening. On this basis the evaluation of screening procedures for melanoma is important, and options for this are discussed. The ideal study design to assess the efficacy of melanoma screening in reducing mortality is a large scale randomised trial. This may need a well coordinated proposal involving several centres in one or more countries, and the cost would be substantial. Without such a trial, however, it is most likely that increasing resources will be put into poorly designed screening programmes of unknown value. The simplest and strongest designs use individual randomisation, but group randomisation designs may have practical advantages, though they require a greater sample size. Designs based on general population screening, and on screening only high risk groups, are both considered. They answer different questions. In countries with high incidence the value of general population screening is probably the more critical. Not enough is known to specify the type and frequency of screening precisely; both screening by doctors and self screening require evaluation, and annual screening should probably be tested. The age range at risk will depend on the local incidence, but is likely to be quite wide-for example, 45-69, and both sexes need inclusion. Thus a suggested design for a moderate to high incidence area would be a trial, randomised by individual or group, assessing at least two annual rounds of both screening by doctor and self screening (ideally by a factorial design), for adults aged 45-69, with mortality over several years' follow up as the critical outcome. In an area with good data systems such a study could compare screening offered to some 260,000 subjects with 10 times that number of controls passively followed up, with 90% power to detect a one third reduction in mortality. A general assessment of costs over five years gave estimates of $8.3 million for the screening programme and $2.4 million for the evaluation. The much weaker designs, area based cohort studies using individual data or a simpler ecological comparison, and case-control studies, are also considered. If well designed with attention to their methodological limitations they may be valuable but are unlikely to be as definitive as a randomised trial.

Adult↗
PubMed1997

Screening status in relation to biological and chronological characteristics of breast cancers: a cross sectional survey.

OBJECTIVE: To determine the pathological and biological characteristics of breast cancers diagnosed by screening and examined at the Edinburgh University pathology department. METHODS: These cancers were classified by screening status: never screened (n = 111), prevalence screen detected (n = 105), and previously screened (n = 74). The last category arose in women who had been regularly screened during the trial; the cancers were diagnosed as interval cases before the first invitation to service screening (n = 33) or were incidence screen detected at that time (n = 41). RESULTS: Association (for operable invasive cancers, n = 250) of cancer characteristics with screening status reflects influences of biology (aggressiveness) or chronology (time of diagnosis), or both. The prognostic indicators tumour grade, histological type, and oestrogen receptor status were found in a smaller percentage of the patients with poor prognosis among the prevalence screen detected cases (9%, 77%, 18%) than among those previously screened (29%, 84%, 35%). The chronological factors size and node status were found in a smaller percentage of patients with poor prognosis among women previously screened (31%, 24%) than among those never screened (62%, 39%). Apart from these two, no other factors improved the diagnosis in the previously screened group compared with the never screened group. CONCLUSIONS: These results suggest that favourable characteristics of screen detected cases are often due to the effects of length bias on "biological factors" and fail to show that current local screening practice has succeeded in advancing the diagnosis of breast cancers to a less aggressive phase.

Breast Neoplasms↗
PubMed1997

Measuring effectiveness of lung cancer screening: from consensus to controversy and back.

BACKGROUND: While intense controversy exists regarding screening for breast, colorectal, and prostate cancer, a consensus exists regarding lung cancer screening. All organizations recommend against any efforts to detect early lung cancer because each of four randomized controlled trials (RCTs) has failed to demonstrate a significant reduction in lung cancer mortality as a result of screening. SYNTHESIS: Disease-specific mortality is assumed to represent the best measure of screening effectiveness in RCTs, because it is not subject to confounding by lead time, length, or overdiagnosis biases. However, the effects of these biases are predictable, so accurate assessments of the degree of confounding by these biases can be made. Moreover, the ability of mortality to accurately reflect cancer death rates depends on the ability of randomization to create experimental and control populations that have an equal risk of dying of the disease under study, except insofar as early detection may reduce that risk. Because the majority of participants in screening trials never develop the disease under investigation, small absolute differences in disease risk between groups often persist despite randomization, and such differences translate into much larger proportional differences in the size of subgroups at risk for disease-specific mortality. This effect confounds the ability of disease-specific mortality to accurately measure screening effectiveness. RESULTS: A total of 18 RCTs have been conducted to evaluate screening for breast, colorectal, and lung cancer. In the only two RCTs that reported a significant mortality reduction for screening mammography in breast cancer, and in the one RCT that reported a significant mortality reduction for fecal occult blood screening in colorectal cancer, population differences led mortality comparisons to overestimate the effectiveness of screening. In lung cancer, no significant mortality reductions have been reported (to my knowledge), but in the two RCTs most directly addressing the effectiveness of chest radiograph (CXR) screening, population differences led mortality comparisons to underestimate the ability of CXRs to reduce the risk of dying of lung cancer. Although mortality is believed to be the best measure of outcome, not a single example can be cited as definitive proof of efficacy for any screening strategy. Thus, screening cannot be recommended for any cancer on the basis of consistent reductions in mortality in RCTs. ANALYSIS: Current policy, which calls for no early detection efforts for lung cancer, implicitly accepts the validity of two contradictory assertions. Conventional wisdom maintains that lung cancer is a highly virulent disease and that metastases are present at inception; accordingly, early detection is ineffective. However, RCTs suggest that lung cancer is an indolent disease and that radiographically detected lesions are clinically unimportant; accordingly, early detection is unnecessary. Such contradictions mandate some rethinking of the fundamental assumptions underlying screening evaluation. CONCLUSIONS: Considerable evidence suggests that annual CXR screening could result in a dramatic reduction in lung cancer mortality in our society. However, proper interpretation of the data depends completely on how screening effectiveness is measured. Given the enormous public health importance of this issue, a consensus conference is recommended to determine whether lung cancer screening can save lives.

Aged↗
PubMed2000

Screening for type 2 diabetes.

Definitive studies of the effectiveness of screening for type 2 diabetes are currently not available. RCTs would be the best means to assess effectiveness, but several barriers prevent these studies from being conducted. Prospective observational studies may characterize some of the benefits of screening by creating screened and unscreened groups for comparison. The availability of better data systems and health services research techniques will facilitate such comparisons. Unfortunately, the interpretation of the results of such studies is extremely problematic. Several screening tests have been evaluated. Risk assessment questionnaires have generally performed poorly as stand-alone tests. Screening with biochemical tests performs better. Venous and capillary glucose measurements may perform more favorably than urinary glucose or HbA(1c) measurements, and measuring postprandial glucose levels may have advantages over measuring fasting levels. However, performance of all screening tests is dependent on the cutoff point selected. Unfortunately, there are no well-defined and validated cutoff points to define positive tests. A two-stage screening test strategy may assist with a more efficient use of resources, although such approaches have not been rigorously tested. The optimal interval for screening is unknown. Even though periodic, targeted, and opportunistic screening within the existing health care system seems to offer the greatest yield and likelihood of appropriate follow-up and treatment, much of the reported experience with screening appears to be episodic poorly targeted community screening outside of the existing health care system. Statistical models have helped to answer some of the key questions concerning areas in which there is lack of empirical data. Current models need to be refined with new clinical and epidemiological information, such as the UKPDS results (200). In addition, future models need to include better information on the natural history of the preclinical phase of diabetes. Data from ongoing clinical trials of screening and treatment of impaired glucose tolerance, such as the Diabetes Prevention Program, may eventually offer more direct evidence for early detection and treatment of asymptomatic hyperglycemia (201). It will be important to use comprehensive cardiovascular disease modules that assess the conjoint influence of glucose and cardiovascular risk factor reduction, information on QOL, and refined economic evaluations using common outcome measures (cost per life-year or QALY gained) (11,178,202-204). Such studies should consider all of the costs associated with a comprehensive screening program, including, at a minimum, the direct costs of screening, diagnostic testing, and care for patients with diabetes detected through screening. Finally, combinations of screening tests and different screening intervals should be evaluated within economic studies to allow selection of the optimal approach within the financial and resource limitations of the health care system.

Blood Glucose↗
PubMed2006

The cost-effectiveness of screening for oral cancer in primary care.

OBJECTIVES: To use a decision-analytic model to determine the incremental costs and outcomes of alternative oral cancer screening programmes conducted in a primary care environment. DESIGN: The cost-effectiveness of oral cancer screening programmes in a number of primary care environments was simulated using a decision analysis model. Primary data on actual resource use and costs were collected by case note review in two hospitals. Additional data needed to inform the model were obtained from published costs, from systematic reviews and by expert opinion using the Trial Roulette approach. The value of future research was determined using expected value of perfect information (EVPI) for the decision to screen and for each of the model inputs. SETTING: Hypothetical screening programmes conducted in a number of primary care settings. Eight strategies were compared: (A) no screen; (B) invitational screen--general medical practice; (C) invitational screen--general dental practice; (D) opportunistic screen--general medical practice; (E) opportunistic screen--general dental practice; (F) opportunistic high-risk screen--general medical practice; (G) opportunistic high-risk screen--general dental practice; and (H) invitational screen--specialist. PARTICIPANTS: A hypothetical population over the age of 40 years was studied. MAIN OUTCOME MEASURES: The main measures were mean lifetime costs and quality-adjusted life-years (QALYs) of each alternative screening scenario and incremental cost-effectiveness ratios (ICERs) to determine the additional costs and benefits of each strategy over another. RESULTS: No screening (strategy A) was always the cheapest option. Strategies B, C, E and H were never cost-effective and were ruled out by dominance or extended dominance. Of the remaining strategies, the ICER for the whole population (age 49-79 years) ranged from pound 15,790 to pound 25,961 per QALY. Modelling a 20% reduction in disease progression always gave the lowest ICERs. Cost-effectiveness acceptability curves showed that there is considerable uncertainty in the optimal decision identified by the ICER, depending on both the maximum amount that the NHS may be prepared to pay and the impact that treatment has on the annual malignancy transformation rate. Overall, however, high-risk opportunistic screening by a general dental or medical practitioner (strategies F and G) may be cost-effective. EVPIs were high for all parameters with population values ranging from pound 8 million to pound 462 million. However, the values were significantly higher in males than females but also varied depending on malignant transformation rate, effects of treatment and willingness to pay. Partial EVPIs showed the highest values for malignant transformation rate, disease progression, self-referral and costs of cancer treatment. CONCLUSIONS: Opportunistic high-risk screening, particularly in general dental practice, may be cost-effective. This screening may more effectively be targeted to younger age groups, particularly 40-60 year olds. However, there is considerable uncertainty in the parameters used in the model, particularly malignant transformation rate, disease progression, patterns of self-referral and costs. Further study is needed on malignant transformation rates of oral potentially malignant lesions and to determine the outcome of treatment of oral potentially malignant lesions. Evidence has been published to suggest that intervention has no greater benefit than 'watch and wait'. Hence a properly planned randomised controlled trial may be justified. Research is also needed into the rates of progression of oral cancer and on referral pathways from primary to secondary care and their effects on delay and stage of presentation.

Aged↗
PubMed1998

Screening for Chlamydia trachomatis in asymptomatic women attending family planning clinics. A cost-effectiveness analysis of three strategies.

BACKGROUND: Screening women for Chlamydia trachomatis in family planning clinics is associated with a reduced incidence of chlamydial sequelae. However, the question of whom to screen to maintain efficient use of resources remains controversial. OBJECTIVE: To assess the cost-effectiveness of chlamydial screening done according to three sets of criteria in asymptomatic women attending family planning clinics. DESIGN: Cost-effectiveness analysis done by using a decision model with the perspective of a health care system. Model estimates were based on analysis of cohort data, clinic costs, laboratory costs, and published data. SETTING: Two family planning clinics in Baltimore, Maryland. PATIENTS: 7699 asymptomatic women who presented between April 1994 and August 1996. INTERVENTION: Three screening strategies--screening according to the criteria of the Centers for Disease Control and Prevention (CDC), screening all women younger than 30 years of age, and universal screening--were retrospectively applied and compared. All women were tested with polymerase chain reaction. MEASUREMENTS: Medical outcomes included sequelae prevented in women, men, and infants. Total costs included screening program costs and future medical costs of all sequelae. The incremental cost-effectiveness ratios of each strategy were calculated. RESULTS: Without screening, 152 cases of pelvic inflammatory disease would occur at a cost of $676,000. Screening done by using the CDC criteria would prevent 64 cases of pelvic inflammatory disease at a cost savings of $231,000. Screening all women younger than 30 years of age would prevent an additional 21 cases of pelvic inflammatory disease and save $74,000. Universal screening would prevent an additional 6 cases of pelvic inflammatory disease but would cost $19,000 more than age-based screening, or approximately $3000 more per case of pelvic inflammatory disease prevented. If the prevalence of C. trachomatis is more than 10.2% or if less than 88.5% of infections occur in women younger than 30 years of age, universal screening provides the greatest cost savings. CONCLUSIONS: These results suggest that age-based screening provides the greatest cost savings of the three strategies examined. However, universal screening is desirable in some situations. In general, screening done by using any criteria and a highly sensitive diagnostic assay should be part of any chlamydial prevention and control program or health plan.

Adolescent↗
PubMed2004

Screening for Chlamydia trachomatis in women 15 to 29 years of age: a cost-effectiveness analysis.

BACKGROUND: Clinical guidelines have traditionally advised annual Chlamydia trachomatis screening for women younger than 25 years of age. OBJECTIVE: To assess the cost-effectiveness of recently proposed strategies for chlamydia screening. DESIGN: State transition simulation model; cost-effectiveness analysis. DATA SOURCES: Published literature. TARGET POPULATION: Sexually active U.S. women 15 to 29 years of age. TIME HORIZON: Lifetime. PERSPECTIVE: Modified societal. INTERVENTIONS: Four strategies targeted to 3 specific age groups (15 to 19 years, 15 to 24 years, and 15 to 29 years): 1) no screening, 2) annual screening for all women, 3) annual screening followed by 1 repeated test within 3 to 6 months after a positive test result, and 4) annual screening followed by selective semiannual screening for women with a history of infection. OUTCOME MEASURES: Clinical events (for example, pelvic inflammatory disease, chronic pelvic pain, ectopic pregnancy, and infertility), lifetime costs, quality-adjusted life expectancy, and incremental cost-effectiveness ratios. RESULTS OF BASE-CASE ANALYSIS: Annual screening in women 15 to 29 years of age followed by semiannual screening for those with a history of infection was the most effective and cost-effective strategy. It consistently had an incremental cost-effectiveness ratio less than 25,000 dollars per quality-adjusted life-year (QALY) compared with the next most effective strategy. When the indirect transmission effects of a 10-year screening program on the probability of infection in uninfected women (that is, per-susceptible rate of infection) were considered, all strategies became more cost-effective. RESULTS OF SENSITIVITY ANALYSIS: Results were sensitive to the annual incidence of chlamydia, probability of persistent infection, screening test costs, and costs of treating long-term complications. Each variable was associated with threshold values beyond which screening became cost-saving. In probabilistic analysis, annual screening in women 15 to 29 years of age followed by semiannual screening for those with a history of infection had an incremental cost-effectiveness ratio less than 50,000 dollars per QALY in 99% of simulations. LIMITATIONS: Uncertainty about the natural history of chlamydial infection and consideration of only the indirect transmission effects of C. trachomatis screening. CONCLUSIONS: Annual C. trachomatis screening for all women 15 to 29 years of age and selective targeting of those with a history of infection for semiannual screening is very cost-effective compared with other well-accepted clinical interventions.

Adolescent↗
PubMedDate not supplied

Breast cancer screening by mammography in women aged under 50 years in Japan.

BACKGROUND: The effectiveness of mammographic screening in women aged over 50 years has been confirmed in the United States and Europe, but its effectiveness in women aged from 40 to 49 years remains controversial. The optimum age for effective screening of subjects for breast cancer by mammography in Japan was studied based on the results of mammographic screening. METHOD: The benefit of breast cancer screening in women was examined by stratifying the results of mammographic screening in a Tokushima trial on the basis of age: under 50 years and 50 years or older. The results of conventional screening by physical examination alone, which we performed in a Zentsuji trial, were used as the control. RESULTS: The examinees numbered 13,982 and 18,619 in mammographic screening and screening by physical examination, respectively. Breast cancer was detected in 43 and 22 patients, respectively. The detection rate of breast cancer was 0.31% by mammographic screening, which is about 3 times higher than that (0.12%) by screening using physical examination. Mammographic screening thus showed significantly higher sensitivity (93.5% vs 73.3%, p = 0.015). The proportion of stage I cancer and the absence of nodal involvement were 67.4% and 79.1% by mammographic screening, compared with 31.8% and 59% by physical examination. Our results obtained with mammographic screening were equal to or higher than the results obtained in the United States and Europe. The clinical stage of the breast cancers detected by mammographic screening in the subjects aged under 50 years was stage 0 (DCIS) in one case and stage I in 10 cases, while the group aged 50 years or older showed stage 0 in 11 cases and stage I in 19 cases. There were three cases of false-negative; two false-negative cases were aged under 50 year, while one case was aged 50 years or older. The detection rates of cancer in the group under 50 years and that of 50 years or more were 0.19% and 0.39% by mammograpic screening and 0.09% and 0.15% by the physical examination. The sensitivities in the group under 50 years and that of 50 years or more were 84.6% and 97.0% by mammographic screening and 72.7% and 73.7% by physical examination, showing no significant difference. In the results of mammograms by Wolfe's classification with respect to the age groups, the proportion of DY (dense breast) pattern decreased significantly from 3.5% to 0.2% in women of 50 years or more and from 16.6% to 2.4% in those under 50 years when the values were compared between the period from 1992 to 1995 and the period from 1998 to 1999, respectively (p < 0.0001). CONCLUSION: The above findings suggested the possible effectiveness of mammographic screening not only in women aged 50 years or more but also in those aged under 50 years, in Japan. Therefore, introduction of mammography should be considered at an early date, even for women aged from 40 to 49 years.

Adult↗
PubMedDate not supplied

Screening for diabetes mellitus in high-risk patients: cost, yield, and acceptability.

CONTEXT: Although universal screening for diabetes mellitus is generally not recommended, recent reports suggest that screening individuals with multiple diabetes risk factors may be worthwhile. Little is known about the cost, yield, or acceptability of this kind of screening. PRACTICE PATTERN EXAMINED: Screening of high-risk patients for diabetes mellitus using a two-step, glucose-based screening protocol: Patients were initially screened with a random glucose test; those with abnormal results received a follow-up fasting, 2-hour, 75-gram oral glucose tolerance test. CLINIC SELECTION: Three volunteer clinics from a large medical group in Minnesota. PATIENT SELECTION: Of 38,989 adults receiving care at the three clinics, we identified 1548 high-risk patients with evidence of both dyslipidemia and hypertension in laboratory and administrative databases. Many of these 1548 patients were not eligible for screening: Twenty-five percent already had diagnosed diabetes; 41% had been screened for diabetes in the past year; and 3% had died, disenrolled, or changed clinics before screening commenced. The remaining 30% (n = 469) were invited for diabetes screening. RESULTS: Of the 469 high-risk patients invited, 206 (44%) initiated screening; 176 (38%) completed diabetes screening. Five new patients with diabetes were identified in this high-risk group (one from the random glucose test and four from the glucose tolerance test). One new patient with diabetes was identified for every 40 high-risk patients screened. The program cost $4064 per new case of diabetes identified (screening costs alone). CONCLUSION: In this high-risk managed care population, the yield and acceptability of systematic diabetes screening were low, and the costs were relatively high. The acceptability of office-based diabetes screening may be improved by using a one-step screening test, such as glycosylated hemoglobin, during routine visits.

Adult↗