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Biomedical subjects

Mary B Barton

Publications and source records attributed to Mary B Barton.

17 recordsLinked to original sources

Efficacy of breast cancer screening in the community according to risk level.

BACKGROUND: The efficacy of breast cancer screening in the community may differ from that suggested by the results of randomized trials, and no data have been available on efficacy among women who have different levels of breast cancer risk. METHODS: We conducted a matched case-control study among women enrolled in six health plans in Washington, Oregon, California, Massachusetts, and Minnesota. We examined the efficacy of screening by mammography and/or clinical breast examination among women in two age cohorts (40-49 years and 50-65 years) and in two breast cancer risk levels (average and increased risk). Women who died from breast cancer from January 1, 1983, through December 31, 1998, (N = 1351; case subjects) were matched to control subjects (N = 2501) on age and risk level. Increased risk was defined as a family history of breast cancer or a breast biopsy noted in the medical records before the index date (defined as date of first suspicion of breast abnormalities in case subjects, with the same date used for matched control subjects). Data on screening, risk status, and other variables were abstracted from medical records. Conditional logistic regression was used to examine the association between breast cancer mortality and receipt of screening. All statistical tests were two-sided. RESULTS: There were small, non-statistically significant associations between breast cancer mortality and receipt of screening during the 3 years prior to the index date for both the younger women [odds ratio (OR) = 0.92; 95% confidence interval (CI) = 0.76 to 1.13] and the older women (OR = 0.87; 95% CI = 0.68 to 1.12). The association among women at increased risk (OR = 0.74; 95% CI = 0.50 to 1.03) was stronger than that among women at average risk (OR = 0.96; 95% CI = 0.80 to 1.14), but the difference was not statistically significant (P = .17). CONCLUSIONS: In this community-based study, screening history was not associated with breast cancer mortality. However, potential limitations of this study argue for a cautious interpretation of these findings.

Adult↗

Impact of IRB requirements on a multicenter survey of prophylactic mastectomy outcomes.

OBJECTIVE: This study assesses the variability in requirements among six institutional review boards (IRBs) and the resulting protocol variations for a multicenter mailed survey. STUDY DESIGN AND SETTING: We utilized a cross-sectional mailed survey to gather information on long-term psychosocial outcomes of prophylactic mastectomy among women at six health maintenance organizations, all of which are part of the Cancer Research Network. In the context of this collaborative study, we characterized the impact of the different sites' IRB review processes on the study protocol and participation. RESULTS: IRB review resulted in site differences in physician consent prior to participant contact, invitation letter content and signatories, and incentive type. The review process required two to eight modifications beyond the initial application and resulted in unanticipated delays and costs. CONCLUSION: Site-to-site variability in IRB requirements may adversely impact scientific rigor and delay implementation of collaborative studies, especially when not considered in project planning. IRB review is an essential aspect of research but one that can present substantial challenges for multicenter studies.

Breast Neoplasms↗

Efficacy of prophylactic mastectomy in women with unilateral breast cancer: a cancer research network project.

PURPOSE: We investigated the efficacy of contralateral prophylactic mastectomy (CPM) in reducing contralateral breast cancer incidence and breast cancer mortality among women who have already been diagnosed with breast cancer. METHODS: This retrospective cohort study comprised approximately 50,000 women who were diagnosed with unilateral breast cancer during 1979 to 1999. Using computerized data confirmed by chart review, we identified 1,072 women (1.9%) who had CPM. We obtained covariate information for these women and for a sample of 317 women who did not undergo CPM. RESULTS: The median time from initial breast cancer diagnosis to the end of follow-up was 5.7 years. Contralateral breast cancer developed in 0.5% of women with CPM, metastatic disease developed in 10.5%, and subsequent breast cancer developed in 12.4%; 8.1% died from breast cancer. Contralateral breast cancer developed in 2.7% of women without CPM, and 11.7% died of breast cancer. After adjustment for initial breast cancer characteristics, treatment, and breast cancer risk factors, the hazard ratio (HR) for the occurrence of contralateral breast cancer after CPM was 0.03 (95% CI, 0.006 to 0.13). After adjustment for breast cancer characteristics and treatment, the HRs for the relationship of CPM with death from breast cancer, with death from other causes, and with all-cause mortality were 0.57 (95% CI, 0.45 to 0.72), 0.78 (95% CI, 0.57 to 1.06), and 0.60 (95% CI, 0.50 to 0.72), respectively. CONCLUSION: CPM seems to protect against the development of contralateral breast cancer, and although women who underwent CPM had relatively low all-cause mortality, CPM also was associated with decreased breast cancer mortality.

Breast Neoplasms↗

A population-based study of bilateral prophylactic mastectomy efficacy in women at elevated risk for breast cancer in community practices.

BACKGROUND: Findings from several studies suggest that bilateral prophylactic mastectomy reduces breast cancer incidence by 90% or more, but the studies used highly selected patients from referral centers, and the comparison groups were not population based. We studied the efficacy of bilateral prophylactic mastectomy in women with elevated breast cancer risk cared for in community practices. METHODS: We conducted a retrospective case-cohort study of women aged 18 to 80 years with 1 or more breast cancer risk factors (family history of breast cancer, history of atypical hyperplasia, or > or =1 breast biopsies with benign findings). Using computerized data and medical records, we identified 276 women with bilateral prophylactic mastectomy and a stratified random sample of 196 women representing an underlying cohort of 666 800 women with elevated breast cancer risk without prophylactic mastectomy, and then we determined who developed breast cancer. RESULTS: Breast cancer developed in 1 woman (0.4%) after bilateral prophylactic mastectomy vs 26 800 women (4.0%) without prophylactic mastectomy. Stratifying by birth year, the hazard ratio for breast cancer occurrence after bilateral prophylactic mastectomy was 0.005 (95% confidence interval, 0.001-0.044). No woman with bilateral prophylactic mastectomy died of breast cancer vs a calculated 0.2% of women without prophylactic mastectomy. CONCLUSIONS: Bilateral prophylactic mastectomy reduced breast cancer incidence in women at elevated risk for breast cancer cared for in community-based practices. However, the absolute risk of breast cancer incidence and death in women who did not undergo the procedure in these settings was relatively low.

Adolescent↗

Screening for colorectal, breast, and cervical cancer in the elderly: a review of the evidence.

There is general consensus that screening can reduce mortality from colorectal, breast, and cervical cancer among persons in their 50s and 60s. However, few screening trials have included persons over age 70 years. Therefore, indirect evidence must be used to determine when results in younger persons should be extrapolated to older persons. In this review, we focus on cancer screening tests that are well accepted in younger persons (mammography, Papanicolaou smears, and colorectal cancer screening) and discuss the strength of inference concerning benefits and harms of screening older persons. Some aspects of aging favor screening (eg, increased absolute risk of dying of cancer) whereas other aspects do not (eg, decreased life expectancy). Age also affects the behavior of some cancers (eg, increases the proportion of slow-growing breast cancers) and affects the accuracy of some screening tests (eg, increases the accuracy of mammography; decreases the accuracy of sigmoidoscopy). These effects make the application of evidence in younger populations to older populations complex. However, given the heterogeneity of the elderly population, there is no evidence of one age at which potential benefits of screening suddenly cease or potential harms suddenly become substantial for everyone. Therefore, characteristics of individual patients that go beyond age should be the driving factors in screening decisions. For example, persons who have a life expectancy less than 5 years or persons who would decline treatment should generally not be screened. Decisions to either continue or discontinue screening in the elderly should be based on health status, the benefits and harms of the test, and preferences of the patient, rather than solely on the age of the patient.

Aged↗

Complications following bilateral prophylactic mastectomy.

BACKGROUND: Bilateral prophylactic mastectomy significantly decreases breast cancer risk, but complications of the procedure have only been described in single-site studies. We describe the frequency and type of complications in women who underwent bilateral prophylactic mastectomy in a multisite community-based cohort. METHODS: Women aged 18-80 years undergoing bilateral prophylactic mastectomy without a personal history of breast cancer at one of six health plans were eligible. We identified women from automated data sources, then reviewed hospital data, ambulatory notes, and other chart elements to confirm eligibility and obtain all charted information about complications and surgeries performed after prophylactic mastectomy, including reconstructive procedures. Reconstructions were characterized by type (implant vs. tissue graft). Complications were noted for a 1-year period after any surgical procedure. RESULTS: We identified 269 women with prophylactic mastectomy who were followed for a mean of 7.4 years. Their mean age was 44.9 years. Nearly 80% undertook reconstruction, most with prosthetic implants. One or more complications occurred in 64%. The most common complications were pain (35% of women), infection (17%), and seroma (17%). Women with no reconstruction had fewer complications (mean of .93) than women who had implant (2.0) or tissue graft (2.4) reconstruction procedures (differences from no reconstruction: 1.07 [95% confidence interval = 0.36 to 1.77] and 1.50 [95% confidence interval = 0.44 to 2.56] respectively). Delay of reconstruction after mastectomy was associated with a borderline-significant higher risk of complications (80.6%) compared to simultaneous reconstruction (64.0%, P = .055). CONCLUSION: We found that almost two-thirds of women undergoing bilateral prophylactic mastectomy had at least one complication following surgery. Further work should be done to minimize and to understand the effect of complications of bilateral prophylactic mastectomy.

Adolescent↗

Screening clinical breast examination: how often does it miss lethal breast cancer?

BACKGROUND: Although most American women regularly receive screening clinical breast examination (CBE), little is known about CBE accuracy in community practice. We sought to estimate the rate of cancer detection (sensitivity) of screening CBE performed by community-based clinicians on women who ultimately died of breast cancer, as well as to identify factors associated with accurate detection. SUBJECTS AND METHODS: We evaluated CBE accuracy among asymptomatic female health plan enrollees in five states (WA, OR, CA, MA, and MN) who received a CBE within 1 year of breast cancer diagnosis and who died of breast cancer within 15 years of diagnosis (N = 485). Sensitivity was estimated as the proportion whose exam was abnormal. Bivariate and logistic regression analyses identified patient characteristics associated with cancer detection. RESULTS: An abnormality was noted on screening CBE in one of five women who ultimately succumbed to breast cancer (sensitivity = 21.6%; 95% confidence interval [CI] = 18.1% to 25.6%). The odds of a true-positive screening CBE (sensitivity) were decreased among women using estrogen (odds ratio [OR] = 0.23; 95% CI = 0.07 to 0.80), receiving a Pap smear during the same visit as CBE (OR = 0.45; 95% CI = 0.27 to 0.72), and with increasing chronic disease comorbidity (P(trend) = .08). CONCLUSION: Screening CBE as performed in the community may be insufficiently sensitive to detect most lethal breast cancers. Low sensitivity of screening CBE in community practice may be partly attributable to its performance alongside time-consuming clinical tasks such as Pap smear screening or chronic illness care.

Adult↗

Race and ethnicity: comparing medical records to self-reports.

Understanding and eliminating health disparities requires accurate data on race/ethnicity. To assess the quality of race/ethnicity data, we compared medical record classifications to self-report of a study of prophylactic mastectomy. A total of 788 women had race/ethnicity from both sources; 69.9% were 55 years of age or older, 38.3% were at least college graduates, and 67.8% were married or living with someone. There were 817 race/thnicity classifications for the 788 women, of which 758 (92.3%) were identical in the medical record and self-report. Sensitivity and positive predictive value were high (86.7%-97.2%) for whites, Asians, and blacks and moderate (64.0% and 68.1%) for Latinas. However, only one of 18 Native Americans was correctly identified in her medical record. Our results indicate that even if the overall accuracy of medical record classifications for race/ethnicity is high, such a finding may obscure substantial inaccuracies in the recording for racial/ethnic minorities, especially Latinas and Native Americans.

Adolescent↗

Breast cancer screening. Benefits, risks, and current controversies.

Mammography is the best tool available for screening for breast cancer. Although the data supporting clinical breast examination are not as strong, this procedure continues to be widely used in the United States. To maximize accuracy of results, women who undergo screening during their premenopausal years should attempt to schedule mammography during the follicular phase of the menstrual cycle. All women should be educated about the benefits and the harms of screening, including the risk of being called back for further testing.

Adult↗

Decreasing women's anxieties after abnormal mammograms: a controlled trial.

BACKGROUND: Few studies have evaluated interventions to decrease a woman's anxiety after she receives an abnormal mammogram (i.e., one with a recommendation for follow-up). We performed a controlled trial to compare the effects of both an immediate reading of mammograms (i.e., a radiology intervention) and of an educational intervention that taught skills to cope with anxiety on the psychological status of women whose mammograms were normal or abnormal. METHODS: Eligible women (n = 8543) aged 39 years or older were recruited from seven mammography sites at the time of their scheduled mammography screening and assigned to receive no intervention, either the radiology or the educational intervention, or both interventions. We used the Impact of Events Scale (IES) and the Hopkins Symptom Checklist subscales for Anxiety (HSC-A) and Depression (HSC-D) in structured telephone interviews of 2844 women to assess the psychological status of all women with abnormal mammograms (excluding women diagnosed with breast cancer) and of a random sample of women with normal mammograms at 3 weeks and 3 months after their mammograms. All statistical tests were two-sided. RESULTS: We obtained usable 3-week interviews for 2390 (84%) women. By the 3-week interview, 1037 (72.1%) of the 1439 interviewed women with abnormal mammograms had completed the recommended work-up and knew that their abnormal mammograms were false positives. Women with abnormal mammograms had higher IES and HSC-A scores (i.e., more anxiety) than women with normal mammograms (mean IES scores: 4.97 [95% confidence interval [CI] = 4.47 to 5.50] and 1.82 [95% CI = 1.51 to 2.14], respectively; P<.001; mean HSC-A scores: 1.14 [95% CI = 1.12 to 1.15] and 1.11 [95% CI = 1.09 to 1.13], respectively, P=.002). Among women with false-positive mammograms, those who had received the radiology intervention reported less anxiety than those who had not (mean IES scores: 4.42 [95% CI = 3.73 to 5.07] and 5.53 [95% CI = 4.82 to 6.28], respectively, P=.026). The educational intervention was not associated with any difference in psychological outcomes. Three months after the mammogram, by which time more than 80% of the women with abnormal results knew their mammograms to be false positives, anxiety levels of women with false-positive mammograms remained higher than those of women with normal mammograms (mean IES scores: 2.34 [95% CI = 1.99 to 2.69] and 1.15 [95% CI = 0.87 to 1.47], respectively, P<.001). CONCLUSION: Immediate reading of screening mammograms, but not an educational intervention targeting coping skills, was associated with less anxiety among women with false-positive mammograms 3 weeks after mammography.

Adult↗

Comparing breast cancer case identification using HMO computerized diagnostic data and SEER data.

OBJECTIVE: To determine the sensitivity and positive predictive value (PPV) of computerized diagnostic data from health maintenance organizations (HMOs) in identifying incident breast cancer cases. STUDY DESIGN: An HMO without a cancer registry developed an algorithm identifying incident breast cancer cases using computerized diagnostic codes. Two other HMO sites with Surveillance, Epidemiology, and End Results (SEER) registries duplicated this case-identification approach. Using the SEER registries as the criterion standard, we determined the sensitivity and PPV of the computerized data. METHODS: Data were collected from HMO computerized data-bases between January 1, 1996, and December 31, 1999. Surveillance, Epidemiology, and End Results data were also used. RESULTS: The overall sensitivity of the HMO databases was between 0.92 (95% confidence interval [CI], 0.91-0.96) and 0.99 (95% CI, 0.98-0.99). Sensitivity was high (range, 0.94-0.98), for the first 3 (of 4) years, dropping slightly (range, 0.81-0.94) in the last year. The overall PPV ranged from 0.34 (95% CI, 0.32-0.35) to 0.44 (95% CI, 0.42-0.46). Positive predictive value rose sharply (range, 0.18-0.20) after the first year to 0.83 and 0.92 in the last year because prevalent cases were excluded. Review of a random sample of 50 cases identified in the computerized data-bases but not by SEER data indicated that, while SEER usually identified the cases, the registry did not associate every case with the health plan. CONCLUSIONS: Health maintenance organization computerized databases were highly sensitive for identifying incident breast cancer cases, but PPV was low in the initial year because the systems did not differentiate between prevalent and incident cases. Health maintenance organizations depending solely on SEER data for cancer case identification will miss a small percentage of cases.

Algorithms↗

Barriers to self-monitoring of blood glucose among adults with diabetes in an HMO: a cross sectional study.

BACKGROUND: Recent studies suggest that patients at greatest risk for diabetes complications are least likely to self-monitor blood glucose. However, these studies rely on self-reports of monitoring, an unreliable measure of actual behavior. The purpose of the current study was to examine the relationship between patient characteristics and self-monitoring in a large health maintenance organization (HMO) using test strips as objective measures of self-monitoring practice. METHODS: This cross-sectional study included 4,565 continuously enrolled adult managed care patients in eastern Massachusetts with diabetes. Any self-monitoring was defined as filling at least one prescription for self-monitoring test strips during the study period (10/1/92-9/30/93). Regular SMBG among test strip users was defined as testing an average of once per day for those using insulin and every other day for those using oral sulfonylureas only. Measures of health status, demographic data, and neighborhood socioeconomic status were obtained from automated medical records and 1990 census tract data. RESULTS: In multivariate analyses, lower neighborhood socioeconomic status, older age, fewer HbA1c tests, and fewer physician visits were associated with lower rates of self-monitoring. Obesity and fewer comorbidities were also associated with lower rates of self-monitoring among insulin-managed patients, while black race and high glycemic level (HbA1c>10) were associated with less frequent monitoring. For patients taking oral sulfonylureas, higher dose of diabetes medications was associated with initiation of self-monitoring and HbA1c lab testing was associated with more frequent testing. CONCLUSIONS: Managed care organizations may face the greatest challenges in changing the self-monitoring behavior of patients at greatest risk for poor health outcomes (i.e., the elderly, minorities, and people living in low socioeconomic status neighborhoods).

Adult↗

Training, quality assurance, and assessment of medical record abstraction in a multisite study.

Clinical studies using medical record review should include careful training and quality assurance methods to enhance the reliability and validity of data obtained from the records. Because of time and budget constraints, comprehensive assessments of data quality and reliability, including masking of medical record abstractors, are not always possible. This paper describes the abstractor training and quality control methods and results of a masked medical record review study. The medical record review study was carried out within a larger multisite study of the effectiveness of screening mammography in preventing breast cancer mortality with an observation period within 1983 and 1993, with mortality follow-up through 1998. An eight-step program was developed to train medical record abstractors and monitor the quality of their work. A key follow-up component to the training protocol was a 5% reabstraction of medical records (n = 160), masked and reviewed by a second abstractor. High agreement was found between initial (unmasked) abstractors and masked abstractors for all key exposure variables (kappa ranged from 0.76 to 0.91), with no evidence of biased directionality by unmasked reviewers. Rigorous ongoing training programs for medical record abstractors provide assurance of good quality control in large multisite studies. Additionally, a masking study with a subsample of subjects may be a feasible and cost-effective alternative to the time- and cost-intensive methodological approach of masking all medical records.

Adult↗

A computerized system to facilitate medical record abstraction in cancer research (United States).

OBJECTIVE: To implement a computerized system to gather and transmit medical record information from six sites to a centralized database for two cancer prevention studies. METHODS: Microsoft Access 97 was selected as the application for the system. Sites purchased Access and hardware meeting technical specifications required for the system. A developer worked with the lead investigator and medical record abstractors to develop a 'back-end' database to hold the desired data while maintaining a user-friendly 'front-end' interface. Abstractors trained on a paper version of the abstraction form were then trained to use the system. Meeting minutes and technical notes were used in summarizing the approach and process. Observations were collected through discussions. RESULTS: We overcame multiple obstacles to develop computerized systems supporting medical record data collection at multiple sites. Although system development slowed implementation of the study, the system produced data for cleaning and analysis immediately. Overall the approach decreased the time from study implementation to manuscript submission. Development time for a second system was substantially reduced. CONCLUSIONS: Computerized systems for medical record abstraction at multiple sites convey substantial benefit. We present a schematic approach to facilitate development of similar systems in the future.

Abstracting and Indexing↗

Screening mammograms by community radiologists: variability in false-positive rates.

BACKGROUND: Previous studies have shown that the agreement among radiologists interpreting a test set of mammograms is relatively low. However, data available from real-world settings are sparse. We studied mammographic examination interpretations by radiologists practicing in a community setting and evaluated whether the variability in false-positive rates could be explained by patient, radiologist, and/or testing characteristics. METHODS: We used medical records on randomly selected women aged 40-69 years who had had at least one screening mammographic examination in a community setting between January 1, 1985, and June 30, 1993. Twenty-four radiologists interpreted 8734 screening mammograms from 2169 women. Hierarchical logistic regression models were used to examine the impact of patient, radiologist, and testing characteristics. All statistical tests were two-sided. RESULTS: Radiologists varied widely in mammographic examination interpretations, with a mass noted in 0%-7.9%, calcification in 0%-21.3%, and fibrocystic changes in 1.6%-27.8% of mammograms read. False-positive rates ranged from 2.6% to 15.9%. Younger and more recently trained radiologists had higher false-positive rates. Adjustment for patient, radiologist, and testing characteristics narrowed the range of false-positive rates to 3.5%-7.9%. If a woman went to two randomly selected radiologists, her odds, after adjustment, of having a false-positive reading would be 1.5 times greater for the radiologist at higher risk of a false-positive reading, compared with the radiologist at lowest risk (95% highest posterior density interval [similar to a confidence interval] = 1.17 to 2.08). CONCLUSION: Community radiologists varied widely in their false-positive rates in screening mammograms; this variability range was reduced by half, but not eliminated, after statistical adjustment for patient, radiologist, and testing characteristics. These characteristics need to be considered when evaluating false-positive rates in community mammographic examination screening.

Adult↗

Breast self-examination: who teaches it, who is taught, and how often? (United States).

BACKGROUND: Although the effectiveness of breast self-examination (BSE) has not been established, it is widely practiced and taught. However, it is not clear which patients and providers are involved in BSE teaching, nor how often it occurs. We undertook this study at a large New England Health Maintenance Organization (HMO) to answer these questions. METHODS: The study was a retrospective cohort of 2242 randomly selected women aged 40-69 with no history of breast cancer and at least one screening clinical breast examination, followed over a ten-year period, including their medical providers (n = 356). Data were collected via computerized medical records. RESULTS: Sixty-eight percent of women had documented BSE teaching at least once in the ten years, increasing from 13% taught in 1983 to 36% in 1993 (p = 0.001). Teaching was related to younger age, increasing numbers of clinical breast examinations, screening mammograms, and prior BSE teachings. Patient race, income, family history of breast cancer, and estrogen replacement use were not related to teaching. Sixty-one percent of all providers taught BSE at least once during the ten years. Internists (OR 6.37, 95% CI 2.23-17.3) and non-physician providers (OR 12.8, 95% CI 3.0-54.4) were more likely to teach at least half of their patients than were obstetrician-gynecologists. Recent medical school graduates taught BSE more often. Provider gender was not associated with teaching. CONCLUSIONS: Over two-thirds of women patients in this HMO setting were taught BSE and the majority of providers taught BSE at least once during the ten years. Rates of teaching tripled over the decade. It is important to establish the effectiveness of BSE and its appropriate role in breast cancer screening.

Adult↗