Biomedical subjects
Russell Harris
Publications and source records attributed to Russell Harris.
Promoting informed choice: transforming health care to dispense knowledge for decision making.
Ours is an era in which patients seek greater engagement in health care choices, increasing the demand for high-quality information about clinical options. Providing support for informed choice is not straightforward, however, because of challenges faced by clinicians, health systems, and consumers. Greater use of written or electronic tools can help to clarify choices for patients, but decision aids cannot replace the human element in facilitating informed choice. The ideal solution is to couple information with high-quality decision counseling to help patients understand the potential risks, benefits, and uncertainties of clinical options and to assist them in selecting the option that best accommodates their personal preferences. Decision counseling can be offered by 3 types of providers: clinicians who lack formal informed-choice training ("usual care"), clinicians with formal informed-choice training, or trained third parties who function as impartial decision counselors. Controlled studies are needed to determine which model is best, but none appears to be ideal. The health care system cannot truly support informed decision making without correcting the underlying obstacles that impede patient access to needed information. New information technology solutions, training programs, and reimbursement schemes are necessary. Patient demand for guidance will only increase as clinical options multiply and the world of information continues its rapid growth. Today's health care system is unprepared for the convergence of these 2 burgeoning domains, and the need to address systemic deficiencies will grow more urgent over time.
Effectiveness: the next question for breast cancer screening.
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Screening for type 2 diabetes mellitus: a cost-effectiveness analysis.
BACKGROUND: No randomized, controlled trial of screening for diabetes has been conducted. In the absence of direct evidence, cost-effectiveness models may provide guidance about preferred screening strategies. OBJECTIVE: To estimate the incremental cost-effectiveness of 2 diabetes screening strategies: screening targeted to people with hypertension and universal screening. DESIGN: Markov model. DATA SOURCES: United Kingdom Prospective Diabetes Study, Hypertension Optimal Treatment trial, and recent cost data. TARGET POPULATION: General primary care population in the United States. TIME HORIZON: Lifetime. PERSPECTIVE: Health care system. INTERVENTIONS: Diabetes screening targeted to people with hypertension and universal screening. OUTCOME MEASURES: Cost per quality-adjusted life-year (QALY) gained. Costs (in 1997 U.S. dollars) and QALYs discounted at a 3% annual rate. RESULTS OF BASE-CASE ANALYSIS: At all ages, incremental cost-effectiveness ratios were more favorable for screening targeted to people with hypertension than for universal screening. For example, at age 55 years, the cost per QALY for targeted screening compared with no screening was 34,375 dollars, whereas the cost per QALY for universal screening compared with targeted screening was 360,966 dollars. Screening was more cost-effective for ages 55 to 75 years than for younger ages. RESULTS OF SENSITIVITY ANALYSIS: In single-way and probabilistic sensitivity analyses, findings were robust to therapy costs, screening costs, screening lead time, reduced effectiveness of intensive antihypertensive therapy, and increased relative risk reduction for stroke attributable to intensive hypertension control. LIMITATIONS: We did not consider screening targeted to persons with dyslipidemia, and we used studies of people whose diabetes was detected clinically to estimate screening benefits. CONCLUSIONS: Diabetes screening targeted to people with hypertension is more cost-effective than universal screening. The most cost-effective strategy is targeted screening at age 55 to 75 years.
Screening and interventions for obesity in adults: summary of the evidence for the U.S. Preventive Services Task Force.
BACKGROUND: Obesity poses a considerable and growing health burden. This review examines evidence for screening and treating obesity in adults. DATA SOURCES: MEDLINE and Cochrane Library (January 1994 through February 2003). STUDY SELECTION: Systematic reviews; randomized, controlled trials; and observational studies of obesity's health outcomes or efficacy of obesity treatment. DATA EXTRACTION: Two reviewers independently abstracted data on study design, sample, sample size, treatment, outcomes, and quality. DATA SYNTHESIS: No trials evaluated mass screening for obesity, so the authors evaluated indirect evidence for efficacy. Pharmacotherapy or counseling interventions produced modest (generally 3 to 5 kg) weight loss over at least 6 or 12 months, respectively. Counseling was most effective when intensive and combined with behavioral therapy. Maintenance strategies helped retain weight loss. Selected surgical patients lost substantial weight (10 to 159 kg over 1 to 5 years). Weight reduction improved blood pressure, lipid levels, and glucose metabolism and decreased diabetes incidence. The internal validity of the treatment trials was fair to good, and external validity was limited by the minimal ethnic or gender diversity of volunteer participants. No data evaluated counseling harms. Primary adverse drug effects included hypertension with sibutramine (mean increase, 0 mm Hg to 3.5 mm Hg) and gastrointestinal distress with orlistat (1% to 37% of patients). Fewer than 1% (pooled samples) of surgical patients died; up to 25% needed surgery again over 5 years. CONCLUSIONS: Counseling and pharmacotherapy can promote modest sustained weight loss, improving clinical outcomes. Pharmacotherapy appears safe in the short term; long-term safety has not been as strongly established. In selected patients, surgery promotes large amounts of weight loss with rare but sometimes severe complications.
Screening for dementia in primary care: a summary of the evidence for the U.S. Preventive Services Task Force.
BACKGROUND: Dementia is a large and growing problem but is often not diagnosed in its earlier stages. Screening and earlier treatment could reduce the burden of suffering of this syndrome. PURPOSE: To review the evidence of benefits and harms of screening for and earlier treatment of dementia. DATA SOURCES: MEDLINE, PsycINFO, EMBASE, the Cochrane Library, experts, and bibliographies of reviews. STUDY SELECTION: The authors developed eight key questions representing a logical chain between screening and improved health outcomes, along with eligibility criteria for admissible evidence for each question. Admissible evidence was obtained by searching the data sources. DATA EXTRACTION: Two reviewers abstracted relevant information using standardized abstraction forms and graded article quality according to U.S. Preventive Services Task Force criteria. DATA SYNTHESIS: No randomized, controlled trial of screening for dementia has been completed. Brief screening tools can detect some persons with early dementia (positive predictive value < or =50%). Six to 12 months of treatment with cholinesterase inhibitors modestly slows the decline of cognitive and global clinical change scores in some patients with mild to moderate Alzheimer disease. Function is minimally affected, and fewer than 20% of patients stop taking cholinesterase inhibitors because of side effects. Only limited evidence indicates that any other pharmacologic or nonpharmacologic intervention slows decline in persons with early dementia. Although intensive multicomponent caregiver interventions may delay nursing home placement of patients who have caregivers, the relevance of this finding for persons who do not yet have caregivers is uncertain. Other potential benefits and harms of screening have not been studied. CONCLUSIONS: Screening tests can detect undiagnosed dementia. In persons with mild to moderate clinically detected Alzheimer disease, cholinesterase inhibitors are somewhat effective in slowing cognitive decline. The effect of cholinesterase inhibitors or other treatments on persons with dementia detected by screening is uncertain.
Screening adults for type 2 diabetes: a review of the evidence for the U.S. Preventive Services Task Force.
BACKGROUND: Type 2 diabetes mellitus is associated with a heavy burden of suffering. Screening for diabetes is controversial. PURPOSE: To examine the evidence that screening and earlier treatment are effective in reducing morbidity and mortality associated with diabetes. DATA SOURCES: MEDLINE, the Cochrane Library, reviews, and experts, all of which addressed key questions about screening. STUDY SELECTION: Studies that provided information about the existence and length of an asymptomatic phase of diabetes; studies that addressed the accuracy and reliability of screening tests; and randomized, controlled trials with health outcomes for various treatment strategies were selected. DATA EXTRACTION: Two reviewers abstracted relevant information using standardized abstraction forms and graded articles according to U.S. Preventive Services Task Force criteria. DATA SYNTHESIS: No randomized, controlled trial of screening for diabetes has been performed. Type 2 diabetes mellitus includes an asymptomatic preclinical phase; the length of this phase is unknown. Screening tests can detect diabetes in its preclinical phase. Over the 10 to 15 years after clinical diagnosis, tight glycemic control probably reduces the risk for blindness and end-stage renal disease, and aggressive control of hypertension, lipid therapy, and aspirin use reduce cardiovascular events. The magnitude of the benefit is larger for cardiovascular risk reduction than for tight glycemic control. The additional benefit of starting these treatments in the preclinical phase, after detection by screening, is uncertain but is probably also greater for cardiovascular risk reduction. CONCLUSIONS: The interventions that are most clearly beneficial during the preclinical phase are those that affect the risk for cardiovascular disease. The magnitude of additional benefit of initiating tight glycemic control during the preclinical phase is uncertain but probably small.
Screening for gestational diabetes: a summary of the evidence for the U.S. Preventive Services Task Force.
OBJECTIVE: To systematically review the evidence for screening for gestational diabetes mellitus (GDM). DATA SOURCES: We established eligibility criteria for relevant studies. We systematically searched MEDLINE and the Cochrane Collaboration Library for studies meeting eligibility criteria. We supplemented this search with further studies identified from reference lists of reviews. METHODS OF STUDY SELECTION: Two reviewers examined each article for eligibility. A single reviewer abstracted relevant data from the included articles; a second reviewer checked the abstractions. We graded the quality of the articles according to criteria developed by the U.S. Preventive Services Task Force. TABULATION, INTEGRATION, AND RESULTS: No well-conducted, randomized, controlled trial provides direct evidence for the health benefits of screening for GDM. The evidence is unclear regarding the optimal screening and reference diagnostic test for GDM. The impact of hyperglycemia on adverse maternal and neonatal health outcomes is probably continuous. Although insulin therapy decreases the incidence of fetal macrosomia for those women with more severe degrees of hyperglycemia, the magnitude of any effect on maternal and neonatal health outcomes is not clear. The evidence is insufficient to determine the magnitude of health benefit for any treatment among the large number of women with GDM at milder degrees of hyperglycemia. We found limited evidence regarding the potential adverse effects of screening for GDM. CONCLUSION: Because of the lack of high-quality evidence concerning critical issues, we are unable to determine the extent to which screening has an important impact on maternal and neonatal health outcomes. A randomized, controlled trial of screening is necessary to answer the many remaining questions.
Screening for prostate cancer: an update of the evidence for the U.S. Preventive Services Task Force.
BACKGROUND: In U.S. men, prostate cancer is the most common noncutaneous cancer and the second leading cause of cancer death. Screening for prostate cancer is controversial. PURPOSE: To examine for the U.S. Preventive Services Task Force the evidence of benefits and harms of screening and earlier treatment. DATA SOURCES: MEDLINE and the Cochrane Library, experts, and bibliographies of reviews. STUDY SELECTION: Researchers developed eight questions representing a logical chain between screening and reduced mortality, along with eligibility criteria for admissible evidence for each question. Admissible evidence was obtained by searching the data sources. DATA EXTRACTION: Two reviewers abstracted relevant information using standardized abstraction forms and graded article quality according to Task Force criteria. DATA SYNTHESIS: No conclusive direct evidence shows that screening reduces prostate cancer mortality. Some screening tests can detect prostate cancer at an earlier stage than clinical detection. One study provides good evidence that radical prostatectomy reduces disease-specific mortality for men with localized prostate cancer detected clinically. No study has examined the additional benefit of earlier treatment after detection by screening. Men with a life expectancy of fewer than 10 years are unlikely to benefit from screening even under favorable assumptions. Each treatment is associated with several well-documented potential harms. CONCLUSIONS: Although potential harms of screening for prostate cancer can be established, the presence or magnitude of potential benefits cannot. Therefore, the net benefit of screening cannot be determined.
Routinely teaching breast self-examination is dead. What does this mean?
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Chemoprevention of breast cancer: a promising idea with an uncertain future.
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Chemoprevention of breast cancer: a summary of the evidence for the U.S. Preventive Services Task Force.
PURPOSE: Chemoprevention offers promise as a strategy for reducing morbidity and mortality from breast cancer in women. This review examined the evidence for the effectiveness of chemoprevention in women without a history of breast cancer. DATA SOURCES: MEDLINE (1966 to December 2001). STUDY SELECTION: English-language, randomized, controlled trials (RCTs) of chemoprevention of breast cancer in women without a previous diagnosis of breast cancer were examined, and 4 relevant trials, 3 involving tamoxifen and 1 involving raloxifene, were selected. Trials that provided data on the harms of tamoxifen or raloxifene, studies of the costs of chemoprevention, and studies of risk assessment were also reviewed. DATA EXTRACTION: Four reviewers independently abstracted data on key variables, including study population, sample size, randomization, treatment, and outcomes. DATA SYNTHESIS: The largest of the RCTs of tamoxifen reported a 49% reduction in relative risk (0.51 [95% CI, 0.39 to 0.66]) for invasive cancer among women with an estimated 5-year breast cancer risk of at least 1.66%. The other tamoxifen trials did not observe a statistically significant benefit, but only a few women in each trial took tamoxifen during the entire study period. The raloxifene study of postmenopausal women with osteoporosis found a 76% reduction in relative risk (0.24 [CI, 0.13 to 0.44]) for invasive breast cancer. Tamoxifen and raloxifene were effective only against estrogen receptor-positive tumors. Both drugs increased risk for venous thromboembolic disease and hot flashes; tamoxifen increased risk for endometrial cancer and stroke. CONCLUSIONS: Tamoxifen and raloxifene reduce the incidence of estrogen receptor-positive breast cancer in women. The relative risk reduction seems similar across all breast cancer risk groups. The absolute risk reduction varies by risk factors for breast cancer, however, and must be balanced against the potential harms to judge the appropriateness of treatment for individual women.