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Biomedical subjects

S W Fletcher

Publications and source records attributed to S W Fletcher.

At least 19 recordsLinked to original sources
PubMed2001

Increased patient concern after false-positive mammograms: clinician documentation and subsequent ambulatory visits.

OBJECTIVE: To measure how often a breast-related concern was documented in medical records after screening mammography according to the mammogram result (normal, or true-negative vs false-positive) and to measure changes in health care utilization in the year after the mammogram. DESIGN: Cohort study. SETTING: Large health maintenance organization in New England. PATIENTS: Group of 496 women with false-positive screening mammograms and a comparison group of 496 women with normal screening mammograms, matched for location and year of mammogram. MEASUREMENTS AND MAIN RESULTS: 1) Documentation in clinicians' notes of patient concern about the breast and 2) ambulatory health care utilization, both breast-related and non-breast-related, in the year after the mammogram. Fifty (10%) of 496 women with false-positive mammograms had documentation of breast-related concern during the 12 months after the mammogram, compared to 1 (0.2%) woman with a normal mammogram (P =.001). Documented concern increased with the intensity of recommended follow-up (P =.009). Subsequent ambulatory visits, not related to the screening mammogram, increased in the year after the mammogram among women with false-positive mammograms, both in terms of breast-related visits (incidence ratio, 3.07; 95% confidence interval [CI], 1.69 to 5.93) and non-breast-related visits (incidence ratio, 1.14; 95% CI, 1.03 to 1.25). CONCLUSIONS: Clinicians document concern about breast cancer in 10% of women who have false-positive mammograms, and subsequent use of health care services are increased among women with false-positive mammogram results.

Adult↗
PubMed2000

Predicting the cumulative risk of false-positive mammograms.

BACKGROUND: The cumulative risk of a false-positive mammogram can be substantial. We studied which variables affect the chance of a false-positive mammogram and estimated cumulative risks over nine sequential mammograms. METHODS: We used medical records of 2227 randomly selected women who were 40-69 years of age on July 1, 1983, and had at least one screening mammogram. We used a Bayesian discrete hazard regression model developed for this study to test the effect of patient and radiologic variables on a first false-positive screening and to calculate cumulative risks of a false-positive mammogram. RESULTS: Of 9747 screening mammograms, 6. 5% were false-positive; 23.8% of women experienced at least one false-positive result. After nine mammograms, the risk of a false-positive mammogram was 43.1% (95% confidence interval [CI] = 36.6%-53.6%). Risk ratios decreased with increasing age and increased with number of breast biopsies, family history of breast cancer, estrogen use, time between screenings, no comparison with previous mammograms, and the radiologist's tendency to call mammograms abnormal. For a woman with highest-risk variables, the estimated risk for a false-positive mammogram at the first and by the ninth mammogram was 98.1% (95% CI = 69.3%-100%) and 100% (95% CI = 99.9%-100%), respectively. A woman with lowest-risk variables had estimated risks of 0.7% (95% CI = 0.2%-1.9%) and 4.6% (95% CI = 1. 1%-12.5%), respectively. CONCLUSIONS: The cumulative risk of a false-positive mammogram over time varies substantially, depending on a woman's own risk profile and on several factors related to radiologic screening. By the ninth mammogram, the risk can be as low as 5% for women with low-risk variables and as high as 100% for women with multiple high-risk factors.

Adult↗
PubMed2000

Breast cancer screening use by African Americans and Whites in an HMO.

OBJECTIVE: To examine racial differences in breast cancer screening in an HMO that provides screening at no cost. DESIGN: Retrospective cohort study of breast cancer screening among African-American and white women. Breast cancer screening information was extracted from computerized medical records. SETTING: A large HMO in New England. PATIENTS/PARTICIPANTS: White and African-American women (N = 2,072) enrolled for at least 10 years in the HMO. MAIN RESULTS: Primary care clinicians documented recommending a screening mammogram significantly more often for African Americans than whites (70% vs 64%; P <.001). During the 10-year period, on average, white women obtained more mammograms (4.49 vs 3.93; P <.0001) and clinical breast examinations (5.35 vs 4.92; P <.01) than African-American women. However, a woman's race was no longer a statistically significant predictor of breast cancer screening after adjustment for differences in age, estimated household income, estrogen use, and body mass index (adjusted number of mammograms, 4.47 vs 4.25, P =.17; and adjusted number of clinical breast examinations, 5.35 vs 5. 31, P =.87). CONCLUSIONS: In this HMO, African-American and white women obtained breast cancer screening at similar rates. Comparisons with national data showed much higher screening rates in this HMO for both white and African-American women.

Adult↗
PubMed1999

The rational clinical examination. Does this patient have breast cancer? The screening clinical breast examination: should it be done? How?

CONTEXT: The clinical breast examination (CBE) is widely recommended and practiced as a tool for breast cancer screening; however, its effectiveness is dependent on its precision and accuracy. OBJECTIVE: To collect evidence on the effectiveness of CBE in screening for breast cancer and information on the best technique to use. DATA SOURCES: We searched the English-language literature using the MEDLINE database (1966-1997) and manual review of all reference lists, as well as contacting investigators of several published studies for clarifications and unpublished data. STUDY SELECTION AND DATA EXTRACTION: To study CBE effectiveness, we included all controlled trials and case-control studies in which CBE was at least part of the screening modality; for technique, we included both clinical studies and those that used silicone breast models. All 3 authors reviewed and agreed on the studies selected for inclusion in the pooled analyses. DATA SYNTHESIS: Randomized clinical trials demonstrated reduced breast cancer mortality rates among women screened by both CBE and mammography. Evidence of CBE's independent contribution was less direct; CBE alone detected between 3% and 45% of breast cancers found that screening mammography missed. The precision of CBE was difficult to determine because of the lack of consistent and standardized examination techniques. Studies on CBE precision reported fair agreement (kappa = 0.22-0.59). Pooling trial data, we estimated CBE sensitivity at 54% and specificity at 94%. The likelihood ratio of a positive CBE result is 10.6 (95% confidence interval [CI], 5.8-19.2), while the likelihood ratio of a negative test result is 0.47 (95% CI, 0.40-0.56). Longer duration of CBE and a higher number of specific techniques used were associated with greater accuracy. The preferred technique for CBE includes proper positioning of the patient, thoroughness of search, use of a vertical-strip search pattern, proper position and movement of the fingers, and a CBE duration of at least 3 minutes per breast. The value of inspection is unproved. Professional and lay examiners improved their sensitivity on silicone breast models after being taught this technique. CONCLUSIONS: Indirect evidence supports the effectiveness of CBE in screening for breast cancer. Although the screening clinical examination by itself does not rule out disease, the high specificity of certain abnormal findings greatly increases the probability of breast cancer.

Adult↗
PubMed1999

Breast symptoms among women enrolled in a health maintenance organization: frequency, evaluation, and outcome.

BACKGROUND: Few data exist about visits to primary care clinicians for breast symptoms in the United States. OBJECTIVE: To determine how often women present with breast symptoms, how these symptoms are evaluated, and how often cancer is diagnosed. DESIGN: Retrospective cohort study. SETTING: Staff-model division of a large health maintenance organization (HMO) in New England. PATIENTS: 2400 women who were 40 to 69 years of age as of 1 July 1983 and were continuously enrolled in the HMO until 30 June 1995. MEASUREMENTS: Information on all breast-related encounters from 1 July 1983 to 30 June 1993 was abstracted. Type of symptom, clinicians' findings and recommendations, and all subsequent evaluations were recorded. Cases of cancer diagnosed subsequent to the symptom were determined. RESULTS: Sixteen percent of the HMO population presented with a breast symptom during the 10-year period, for a rate of 22.8 presentations per 1000 person-years. Women younger than 50 years of age presented nearly twice as often as older women (P = 0.001). Women with breast symptoms had lower rates of screening than other women before presenting but higher rates of screening afterward (P < 0.001). Symptoms were evaluated beyond the initial visit in 66% of patients, and invasive procedures were performed in 27% of patients. Cancer was found in 6.2% of patients and 4.5% of episodes; rates of cancer detection varied significantly by type of symptom but not by patient age. CONCLUSIONS: Breast symptoms among women 40 to 70 years of age were common in this primary care practice. Evaluation beyond initial examinations was frequent, and invasive procedures were performed for 27% of patients. Cancer was diagnosed in more than 4% of episodes, indicating that follow-up of breast symptoms is important in primary care practices.

Adult↗
PubMed1999

A worldwide assessment of medical journal editors' practices and needs--results of a survey by the World Association of Medical Editors.

OBJECTIVES: To identify editors interested in participating in a global organisation and communication network of medical editors; to assess current use of the peer-review process; and to determine current computer capabilities, needs, and interests of medical journal editors around the world. DESIGN: Mail survey of senior editors at 727 medical journals. SETTING: Fifty-seven countries worldwide. RESULTS: Two hundred and sixty-nine editors (37%) responded. Eighty-seven per cent of responding editors expressed interest in a global organisation of medical editors. Almost all editors (94%) reported using peer-review systems. Practices varied widely across journals, but in most cases were not highly correlated with the countries' level of development: 44% reported formal orientation for reviewers; 71% used specific instructions; 39% required reviewers to disclose conflicts of interest; 36% masked the identity of authors; and 42% graded reviews for quality. Seventy-eight per cent of editors reported using a computer in their work and 47% had Internet access; two-thirds of those without access expected to have Internet access within 18 months. CONCLUSIONS: There was strong interest among respondents in a global organisation for medical editors. Peer review was widely reported by medical journal editors throughout the world, although specific practices varied widely. Half of the responding editors reported having access to the Internet, making participation in a worldwide computer network of editors feasible.

Computers↗
PubMed1998

Ten-year risk of false positive screening mammograms and clinical breast examinations.

BACKGROUND: The cumulative risk of a false positive result from a breast-cancer screening test is unknown. METHODS: We performed a 10-year retrospective cohort study of breast-cancer screening and diagnostic evaluations among 2400 women who were 40 to 69 years old at study entry. Mammograms or clinical breast examinations that were interpreted as indeterminate, aroused a suspicion of cancer, or prompted recommendations for additional workup in women in whom breast cancer was not diagnosed within the next year were considered to be false positive tests. RESULTS: A total of 9762 screening mammograms and 10,905 screening clinical breast examinations were performed, for a median of 4 mammograms and 5 clinical breast examinations per woman over the 10-year period. Of the women who were screened, 23.8 percent had at least one false positive mammogram, 13.4 percent had at least one false positive breast examination, and 31.7 percent had at least one false positive result for either test. The estimated cumulative risk of a false positive result was 49.1 percent (95 percent confidence interval, 40.3 to 64.1 percent) after 10 mammograms and 22.3 percent (95 percent confidence interval, 19.2 to 27.5 percent) after 10 clinical breast examinations. The false positive tests led to 870 outpatient appointments, 539 diagnostic mammograms, 186 ultrasound examinations, 188 biopsies, and 1 hospitalization. We estimate that among women who do not have breast cancer, 18.6 percent (95 percent confidence interval, 9.8 to 41.2 percent) will undergo a biopsy after 10 mammograms, and 6.2 percent (95 percent confidence interval, 3.7 to 11.2 percent) after 10 clinical breast examinations. For every 100 dollars spent for screening, an additional 33 dollars was spent to evaluate the false positive results. CONCLUSIONS: Over 10 years, one third of women screened had an abnormal test result that required additional evaluation, even though no breast cancer was present. Techniques are needed to decrease false positive results while maintaining high sensitivity. Physicians should educate women about the risk of a false positive result from a screening test for breast cancer.

Adult↗
PubMed1997

Breast cancer screening among women in their forties: an overview of the issues.

This article summarizes the issues prompting a recent NIH Consensus Conference on mammography screening for women in their forties. To date, eight randomized controlled trials of breast cancer screening have been conducted, and a reduction in breast cancer mortality has emerged after 10 to 15 years of follow-up among women offered screening in their forties. No effect appears for at least eight years, and the reason for the delay, compared to that seen in women aged 50-69, is not clear. Two possibilities include cancer-stage shift due to screening in younger women and the aging of women into their fifties during the course of screening. Possible adverse effects of screening include radiation risk, although this is low, false-negative and false-positive screening tests, and overdiagnosis due to detection of ductal carcinoma in situ (DCIS). In order to make appropriate decisions regarding mammography, women need age-related information about both the benefits and potential risks of screening.

Adult↗
PubMed1995

General internal medicine.

Patients with insulin-dependent diabetes mellitus and microalbuminuria have a reduced rate of progression to clinical proteinuria if treated with captopril. Benefits of zidovudine use are balanced by reductions in quality of life. A panel concluded that 90% of patients with acute low back pain recover spontaneously in 4 weeks.

Humans↗