Showing papers on "Mass screening published in 2000"

The effect of fecal occult-blood screening on the incidence of colorectal cancer.

Abstract: Background Both annual testing for fecal occult blood and biennial testing significantly reduce mortality from colorectal cancer. However, the effect of screening on the incidence of colorectal cancer remains uncertain, despite the diagnosis and removal of precancerous lesions in many persons who undergo screening. Methods We have followed the participants in the Minnesota Colon Cancer Control Study for 18 years. A total of 46,551 people, most of whom were 50 to 80 years old, were enrolled between 1975 and 1978 and randomly assigned to annual screening, biennial screening, or usual care (the control group). Those assigned to the screening groups were asked to prepare and submit two samples from each of three consecutive stools for guaiac-based testing. Those with at least one positive slide in the set of six were offered a diagnostic examination that included colonoscopy. Screening was conducted between 1976 and 1982 and again between 1986 and 1992. Study participants have been followed with respect to ne...

Practice parameter: Screening and diagnosis of autism Report of the Quality Standards Subcommittee of the American Academy of Neurology and the Child Neurology Society

Abstract: Autism is a common disorder of childhood, affecting 1 in 500 children. Yet, it often remains unrecognized and undiagnosed until or after late preschool age because appropriate tools for routine developmental screening and screening specifically for autism have not been available. Early identification of children with autism and intensive, early intervention during the toddler and preschool years improves outcome for most young children with autism. This practice parameter reviews the available empirical evidence and gives specific recommendations for the identification of children with autism. This approach requires a dual process: 1) routine developmental surveillance and screening specifically for autism to be performed on all children to first identify those at risk for any type of atypical development, and to identify those specifically at risk for autism; and 2) to diagnose and evaluate autism, to differentiate autism from other developmental disorders.

Screening for type 2 diabetes.

Abstract: 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.

Accuracy of the Papanicolaou test in screening for and follow-up of cervical cytologic abnormalities: a systematic review.

Abstract: Purpose To evaluate the accuracy of conventional and new methods of Papanicolaou (Pap) testing when used to detect cervical cancer and its precursors. Data sources Systematic search of English-language literature through October 1999 using MEDLINE, EMBASE, other computerized databases, and hand searching. Study selection All studies that compared Pap testing (conventional methods, computer screening or rescreening, or monolayer cytology) with a concurrent reference standard (histologic examination, colposcopy, or cytology). Data extraction Two reviewers independently reviewed selection criteria and completed 2 x 2 tables for each study. Data synthesis 94 studies of the conventional Pap test and three studies of monolayer cytology met inclusion criteria. No studies of computerized screening were included. Data were organized by cytologic and histologic thresholds used to define disease. For conventional Pap tests, estimates of sensitivity and specificity varied greatly in individual studies. Methodologic quality and frequency of histologic abnormalities also varied greatly between studies. In the 12 studies with the least biased estimates, sensitivity ranged from 30% to 87% and specificity ranged from 86% to 100%. Conclusions Insufficient high-quality data exist to estimate test operating characteristics of new cytologic methods for cervical screening. Future studies of these technologies should apply adequate reference standards. Most studies of the conventional Pap test are severely biased: The best estimates suggest that it is only moderately accurate and does not achieve concurrently high sensitivity and specificity. Cost-effectiveness models of cervical cancer screening should use more conservative estimates of Pap test sensitivity.

Breast Density as a Predictor of Mammographic Detection: Comparison of Interval- and Screen-Detected Cancers

Abstract: Background Screening mammography is the best method to reduce mortality from breast cancer, yet some breast cancers cannot be detected by mammography. Cancers diagnosed after a negative mammogram are known as interval cancers. This study investigated whether mammographic breast density is related to the risk of interval cancer. Methods Subjects were selected from women participating in mammographic screening from 1988 through 1993 in a large health maintenance organization based in Seattle, WA. Women were eligible for the study if they had been diagnosed with a first primary invasive breast cancer within 24 months of a screening mammogram and before a subsequent one. Interval cancer case subjects (n = 149) were women whose breast cancer occurred after a negative or benign mammographic assessment. Screen-detected control subjects (n = 388) were diagnosed after a positive screening mammogram. One radiologist, who was blinded to cancer status, assessed breast density by use of the American College of Radiology Breast Imaging Reporting and Data System. Results Mammographic sensitivity (i.e., the ability of mammography to detect a cancer) was 80% among women with predominantly fatty breasts but just 30% in women with extremely dense breasts. The odds ratio (OR) for interval cancer among women with extremely dense breasts was 6.14 (95% confidence interval [CI] = 1.95-19.4), compared with women with extremely fatty breasts, after adjustment for age at index mammogram, menopausal status, use of hormone replacement therapy, and body mass index. When only those interval cancer cases confirmed by retrospective review of index mammograms were considered, the OR increased to 9.47 (95% CI = 2.78-32.3). Conclusion Mammographic breast density appears to be a major risk factor for interval cancer.

Identification of Patients at Increased Risk of First Unheralded Acute Myocardial Infarction by Electron-Beam Computed Tomography

Abstract: Background —There is a clear relationship between absolute calcium scores (CS) and severity of coronary artery disease. However, hard coronary events have been shown to occur across all ranges of CS. Methods and Results —We conducted 2 analyses: in group A, 172 patients underwent electron-beam CT (EBCT) imaging within 60 days of suffering an unheralded myocardial infarction. In group B, 632 patients screened by EBCT were followed up for a mean of 32±7 months for the development of acute myocardial infarction or cardiac death. The mean patient age and prevalence of coronary calcification were similar in the 2 groups (53±8 versus 52±9 years and 96% each). In group B, the annualized event rate was 0.11% for subjects with CS of 0, 2.1% for CS 1 to 99, 4.1% for CS 100 to 400, and 4.8% for CS >400, and only 7% of the patients had CS >400. However, mild, moderate, and extensive absolute CSs were distributed similarly between patients with events in both groups (34%, 35%, and 27%, respectively, in group A and 44%, 30%, and 22% in group B). In contrast, the majority of events in both groups occurred in patients with CS >75th percentile (70% in each group). Conclusions —Coronary calcium is present in most patients who suffer acute coronary events. Although the event rate is greater for patients with high absolute CSs, few patients have this degree of calcification on a screening EBCT. Conversely, the majority of events occur in individuals with high CS percentiles. Hence, CS percentiles constitute a more effective screening method to stratify individuals at risk.

Prognosis with Parkinson's disease in europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group.

Abstract: Data are lacking on the prognosis (institutionalization and death) of PD cases identified in population-based studies. Data from five population-based European studies were compared and pooled. Each study used comparable two-step screening methods to identify cases and performed one or more follow-up examinations of their respective participants after defined periods of time. PD was classified on the basis of questionnaire and clinical data. The studies include 16,143 participants (252 with PD). The relative risk (RR) (95% CI) of death associated with PD was 2.3 (1.8 to 3.0). The risk for death in men with PD (RR 3.1 [2.1 to 4.4]) was higher than in women with PD (RR 1. 8 [1.2 to 5.1]). The rate of institutionalization varied across studies, increased with age, and was considerably higher in PD cases compared to noncases. Women with PD had a fivefold higher risk to live in a care facility than did men with PD. These data on mortality and rate of institutionalization reflect the high burden of PD in the population.

Psychopathic traits and conduct problems in community and clinic-referred samples of children: further development of the psychopathy screening device.

Abstract: This study examined the structure of psychopathic traits in 2 samples of children. The nonreferred community sample included 1,136 children recruited from elementary schools in 2 school districts in the southeastern United States. The clinic sample included 160 children referred to an outpatient mental health clinic serving the same geographic region. In both samples, parent and teacher ratings of psychopathic traits were subjected to a principal-axis factor analysis, and the congruence of the factor structure across samples was examined using confirmatory factor analysis. In both samples, 1 dimension that consisted of the callous and unemotional traits that have been hallmarks of most clinical descriptions of psychopathy was isolated. Two other dimensions consisting of narcissistic traits and impulsivity emerged in the community sample. Both the narcissism and impulsivity dimensions were highly related to symptoms of oppositional defiant disorder, conduct disorder, and attention deficit hyperactivity disorder. However, the callous and unemotional traits were only weakly associated with these symptoms after controlling for the other dimensions of psychopathy.

Ovarian cancer: epidemiology, biology, and prognostic factors.

Abstract: Ovarian cancer varies widely in frequency among different geographic regions and ethnic groups, with a high incidence in Northern Europe and the United States, and a low incidence in Japan. The majority of cases are sporadic, and only 5% to 10% of ovarian cancers are familial. The etiology of ovarian cancer is poorly understood. Models of ovarian carcinogenesis include the theory of incessant ovulation, in which a person's age at ovulation, i.e., lifetime number of ovulatory cycles, is an index of her ovarian cancer risk. Excessive gonadotropin and androgen stimulation of the ovary have been postulated as contributing factors. Exposure of the ovaries to pelvic contaminants and carcinogens may play a role in the pathogenesis of ovarian cancer. Epidemiologic and molecular-genetic studies identify numerous risk and protective factors. The most significant risk factor is a family history of the disease. Recent advances in molecular genetics have found mutations in the BRCA1 and BRCA2 tumor suppressor genes responsible for the majority of hereditary ovarian cancer. Additional risk factors include nulliparity and refractory infertility. Protective factors include multiparity, oral contraceptives, and tubal ligation or hysterectomy. With five years of oral contraceptive use, women can cut their risk of ovarian cancer approximately in half; this also holds true for individuals with a family history. Stage at diagnosis, maximum residual disease following cytoreductive surgery, and performance status are the three major prognostic factors. Using a multimodality approach to treatment, including aggressive cytoreductive surgery and combination chemotherapy, five-year survival rates are as follows: Stage I (93%), Stage II (70%), Stage III (37%), and Stage IV (25%). Semin. Surg. Oncol. 19:3–10, 2000. © 2000 Wiley-Liss, Inc.

The Aneurysm Detection and Management Study Screening Program Validation Cohort and Final Results

Abstract: Background We previously reported the prevalence and associations of abdominal aortic aneurysm (AAA) in 73,451 veterans aged 50 to 79 years who underwent ultrasound screening. Objective To understand the prevalence of and principal positive and negative risk factors for AAA, and to assess reproducibility of our previous findings. Methods In the new cohort of veterans undergoing screening, 52,745 subjects aged 50 to 79 without history of AAA underwent successful ultrasound screening for AAA, after completing a questionnaire on demographics and potential risk factors. Results We detected AAA of 4.0 cm or larger in 613 participants (1.2%; compared with 1.4% in the earlier cohort). The direction and magnitude of the important associations reported in the first cohort were confirmed. Respective odds ratios for the major associations with AAA for the second and for the combined cohorts were as follows: 1.81 and 1.71 for age (per 7 years), 0.12 and 0.18 for female sex, 0.59 and 0.53 for black race, 1.94 and 1.94 for family history of AAA, 4.45 and 5.07 for smoking, 0.50 and 0.52 for diabetes, and 1.60 and 1.66 for atherosclerotic diseases. The excess prevalence associated with smoking accounted for 75% of all AAAs of 4.0 cm or larger in the total population of 126,196. Associations for AAA of 3.0 to 3.9 cm were similar but tended to be somewhat weaker. Conclusions Our findings confirm our previous cohort findings. Age, smoking, family history of AAA, and atherosclerotic diseases remained the principal positive associations with AAA, and female sex, diabetes, and black race remained the principal negative associations.

Maternal thyroid deficiency and pregnancy complications: implications for population screening.

Abstract: Objective—To examine the relation between certain pregnancy complications and thyroid stimulating hormone (TSH) measurements in a cohort of pregnant women. Methods—TSH was measured in sera obtained from women during the second trimester as part of routine prenatal care. Information was then collected about vaginal bleeding, premature delivery, low birthweight, abruptio placentae, pregnancy induced hypertension, need for cesarean section, low Apgar scores, and fetal and neonatal death. Results—Among 9403 women with singleton pregnancies,TSH measurements were 6 mU/l or greater in 209 (2.2%).The rate of fetal death was significantly higher in those pregnancies (3.8%) than in the women with TSH less than 6 mU/l (0.9%, odds ratio 4.4, 95% confidence interval 1.9‐9.5). Other pregnancy complications did not occur more frequently Conclusion—From the second trimester onward, the major adverse obstetrical outcome associated with raised TSH in the general population is an increased rate of fetal death. If thyroid replacement treatment avoided this problem this would be another reason to consider population screening. (J Med Screen 2000;7:127‐130)

Screening for lung cancer.

Abstract: Lung cancer is the leading cause of death from cancer among men and women in the United States. More people die each year of lung cancer than of colon, breast, and prostate cancer combined. Despite new diagnostic techniques, the overall five-year survival rates remain about 14 percent, and most patients still present with advanced disease.1 There has long been interest in screening to detect lung cancers when they are smaller and presumably at earlier and more curable stages, as witnessed by the support for previous screening trials using chest radiography and cytologic examination of sputum. Unfortunately, these studies failed to . . .

Breast MR Imaging Screening in 192 Women Proved or Suspected to Be Carriers of a Breast Cancer Susceptibility Gene: Preliminary Results

Abstract: PURPOSE: To compare magnetic resonance (MR) imaging with conventional imaging in screening high-risk women. MATERIALS AND METHODS: This prospective trial included 192 asymptomatic and six symptomatic women who, on the basis of personal or family history or genetic analysis, were suspected or proved to carry a breast cancer susceptibility gene. RESULTS: Fifteen breast cancers were identified: nine in the 192 asymptomatic women (six in the first and three in the second screening round) and six in the symptomatic patients. Concerning the asymptomatic women, four of the nine breast cancers were detected and correctly classified with mammography and ultrasonography (US) combined; another two cancers were visible as well-circumscribed masses and were diagnosed as fibroadenomas. MR imaging allowed the correct classification and local staging of all nine cancers. In 105 asymptomatic women with validation of the 1st-year screening results, the sensitivities of mammography, US, and MR imaging were 33%, 33% (mammogr...

Growth rate of small lung cancers detected on mass CT screening.

Abstract: CT has recently been used in mass screening for lung cancer. Small cancers have been identified but the growth characteristics of these lesions are not fully understood. We identified 82 primary cancers in our 3-year mass CT screening programme, of which 61 were examined in the present study. The volume doubling time (VDT) was calculated based on the exponential model using successive annual CT images or follow-up CT images. All cases were also examined in the hospital by high resolution CT (HRCT). Lesions were divided into three types based on HRCT characteristics: type G (n = 19), ground glass opacity (GGO); type GS (n = 19), focal GGO with a solid central component; and type S (n = 23), solid nodule. 18 (95%) lesions of type G, 18 (95%) of type GS and 7 (30%) of type S were invisible on conventional chest radiographs. The mean size of the tumour was 10 mm, 11 mm and 16 mm for type G, type GS and type S, respectively. Most tumours (80%) were adenocarcinomas; 78% of these were GGO (type G and GS). Mean VDT values were 813 days, 457 days and 149 days for type G, type GS and type S, respectively; these are significantly different from each other (p < 0.05). Our results show that annual mass screening CT for 3 successive years resulted in the identification of a large number of slowly growing adenocarcinomas that were not visible on chest radiographs.

Impact, Diagnosis and Treatment of von Willebrand Disease*

Abstract: Von Willebrand disease (VWD) is one of the most common inherited bleeding diseases. Based on a conservative estimate of prevalence (at least 100 per million persons) (1-7) and a population of 5.8 billion, there are at least 580,000 persons with symptomatic VWD worldwide who could benefit from appropriate diagnosis followed by replacement or pharmacological therapy. Approximately 80% of these persons live in the developing world. Because severe menorrhagia is common in VWD, the disease tends to cause greater morbidity in women of childbearing age. Consequently, VWD impairs the health of a critical segment of the population during a time of life when the demands of work and family are the greatest.

Type 2 diabetes mellitus in Canada‚s First Nations: status of an epidemic in progress

Abstract: This review provides a status report on the epidemic of type 2 diabetes mellitus that is affecting many of Canada's First Nations. We focus on the published literature, especially reports published in the past 2 decades, and incorporate data from the Aboriginal Peoples Survey and the First Nations and Inuit Regional Health Survey. We look at the extent and magnitude of the problem, the causes and risk factors, primary prevention and screening, clinical care and education, and cultural concepts and traditional knowledge. The epidemic of type 2 diabetes is still on the upswing, with a trend toward earlier age at onset. Genetic-environmental interactions are the likely cause. Scattered intervention projects have been implemented and evaluated, and some show promise. The current health and social repercussions of the disease are considerable, and the long-term outlook remains guarded. A national Aboriginal diabetes strategy is urgently needed.

Using Implementation Intentions to Increase Attendance for Cervical Cancer Screening

Abstract: This article evaluates an intervention based on P. M. Gollwitzer's (1993) concept of implementation intentions. Women registered at a medical practice in rural England (N = 114) completed measures of the theory of planned behavior variables before a manipulation that induced one half of the sample to form implementation intentions specifying when, where, and how they would make the appointment. Subsequent attendance was determined from medical records. Findings show that the theory of planned behavior variables and previous delay behavior provided good prediction of attendance. However, despite equivalent motivation to attend, participants who formed implementation intentions were much more likely to attend for screening compared with controls (92% vs. 69%). Evidence also suggests that implementation intentions attenuated the relationship between previous delay behavior and subsequent attendance.

Effect of NHS breast screening programme on mortality from breast cancer in England and Wales, 1990-8: comparison of observed with predicted mortality.

Abstract: Objective: To assess the impact of the NHS breast screening programme on mortality from breast cancer in women aged 55-69 years over the period 1990-8. Design: Age cohort model with data for 1971-89 used to predict mortality for 1990-8 with assumption of no major effect from screening or improvements in treatment until after 1989. Effect of screening and other factors on mortality estimated by comparing three year moving averages of observed mortality with those predicted (by five year age groups from 50-54 to 75-79), the effect of screening being restricted to certain age groups. Setting: England and Wales. Subjects: Women aged 40 to 79 years. Results: Compared with predicted mortality in the absence of screening or other effects the total reduction in mortality from breast cancer in 1998 in women aged 55-69 was estimated as 21.3%. Direct effect of screening was estimated as 6.4% (range of estimates from 5.4-11.8%). Effect of all other factors (improved treatment with tamoxifen and chemotherapy, and earlier presentation outside the screening programme) was estimated as 14.9% (range 12.2-14.9%). Conclusions: By 1998 both screening and other factors, including improvements in treatment, had resulted in substantial reductions in mortality from breast cancer. Many deaths in the 1990s will be of women diagnosed in the 1980s and early 1990s, before invitation to screening. Further major effects from screening and treatment are expected, which together with cohort effects should result in further substantial reductions in mortality from breast cancer, particularly for women aged 55-69, over the next 10 years.

The Symptom Check-List-90-R (SCL-90-R): a German validation study.

Abstract: The Symptom Check-List-90-R (SCL-90-R) is a widely used psychological status symptom inventory. The properties of the German SCL-90-R version were studied in two clinical samples: psychosomatic outpatients and primary care patients. The data were compared with a German community sample. The internal consistency, measured by Cronbach's alpha coefficients, was found to be high, for the global scale and all original subscales. Mokken scale analysis indicated hierarchical structure for most of the subscales. Concurrent validity, evaluated by studying the relationship between the SCL-90-R subscales and the Inventory of Interpersonal Problems (IIP-C) and the General Health Questionnaire (GHQ-12) was also high. On the basis of receiver operating characteristic (ROC) analyses, it was found that the SCL-90-R was able to differentiate between subjects known to have a given psychological disorder and those who do not. Results of exploratory and confirmatory factor analysis failed to support the original nine factor model and two subsequent factor models. The strong interdependence of the original subscales and the strong first unrotated factor of the exploratory factor analyses raised concern regarding the multi-dimensionality of the SCL-90-R subscales. We concluded that the SCL-90-R is a useful tool for measuring psychological status, measuring change in outcome studies, or screening for mental disorders.

Development and validation of the Osteoporosis Risk Assessment Instrument to facilitate selection of women for bone densitometry

Abstract: BACKGROUND: Although mass screening for osteoporosis is not recommended among postmenopausal women, there is no consensus on which women should undergo testing for low bone mineral density. The objective of this study was to develop and validate a clinical tool to help clinicians identify which women are at increased risk for osteoporosis and should therefore undergo further testing with bone densitometry. METHODS: Using Ontario baseline data from the Canadian Multicentre Osteoporosis Study, we identified all cognitively normal women aged 45 years or more who had undergone testing with dual-energy x-ray absorptiometry (DXA) at both the femoral neck and the lumbar spine (L1-L4). Participants who had a previous diagnosis of osteoporosis or were taking bone active medication other than ovarian hormones were excluded. The main outcome measure was low bone mineral density (T score of 2 or more standard deviations below the mean for young Canadian women) at either the femoral neck or the lumbar spine. Logistic regression analysis and receiver operating characteristic (ROC) analysis were used to identify the simplest algorithm that would identify women at increased risk for low bone mineral density. RESULTS: The study population comprised 1376 women, of whom 926 were allocated to the development of the tool and 450 to its validation. A simple algorithm based on age, weight and current estrogen use (yes or no) was developed. Validation of this 3-item Osteoporosis Risk Assessment Instrument (ORAI) showed that the tool had a sensitivity of 93.3% (95% confidence interval [CI] 86.3%-97.0%) and a specificity of 46.4% (95% CI 41.0%-51.8%) for selecting women with low bone mineral density. The sensitivity of the instrument for selecting women with osteoporosis was 94.4% (95% CI 83.7%-98.6%). Use of the ORAI represented a 38.7% reduction in DXA testing compared with screening all women in our study. INTERPRETATION: The ORAI accurately identifies the vast majority of women likely to have low bone mineral density and is effective in substantially decreasing the need for all women to undergo DXA testing.