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Balk, E.M., Bonis, P.A., Moskowitz, H., and others. (2002, June). "Correlation of quality measures with estimates of treatment effect in meta-analyses of randomized controlled trials." (AHRQ contract 290-97-0019). Journal of the American Medical Association 287(22), pp. 2973-2982.

Specific features of clinical trial quality, such as caregiver blinding and handling of dropouts, may be associated with exaggeration or shrinking of the observed treatment effect. Therefore, assessment of trial quality is often used in meta- analysis of multiple trials. However, the degree to which specific quality measures are associated with treatment effects has not been well established across a broad range of clinical areas. These researchers evaluated 24 quality measures from published quality assessment scales in 276 randomized controlled trials included in 26 meta-analyses from four medical areas. None of the individual quality measures was reliably associated with the strength of treatment effect across studies and medical areas. The researchers conclude that association of specific quality measures with treatment effect cannot be generalized to all clinical areas or meta-analyses.

Coulter, I.D., Favreau, J.T., Hardy, M.L., and others. (2002, June). "Biofeedback interventions for gastrointestinal conditions: A systematic review." (AHRQ contract 290-97-0001). Alternative Therapies 8(3), pp. 76-83.

Four common gastrointestinal (GI) conditions have proven difficult to treat with conventional therapy: irritable bowel syndrome (IBS, stress-related lower abdominal pain and diarrhea/ constipation), adult constipation, adult fecal incontinence, and constipation with fecal incontinence in children. According to the results of a review of studies on the topic, biofeedback is not an effective alternative for treating these conditions. Biofeedback is a method that provides information to a patient about a targeted physiologic process that enables the individual to control that process through mental activity. Medicare currently covers biofeedback for several conditions, including fecal and urinary incontinence. Researchers at the Southern California Evidence-based Practice Center found 16 controlled trials of biofeedback for GI problems out of a review of over 4,000 articles and abstracts. The identified studies had significant methodological flaws, and the researchers determined that the evidence was insufficient to support the efficacy of biofeedback for these GI conditions.

Covinsky, K.E., Covinsky, K.H., Palmer, R.M., and Sehgal, A.R. (2002). "Serum albumin concentration and clinical assessments of nutritional status in hospitalized older people: Different sides of different coins?" (AHRQ grant K02 HS00006). Journal of the American Geriatrics Society 50(4), pp. 631-637.

Malnutrition is common in older hospitalized medical patients, often goes unrecognized, and is strongly associated with complications and death. As a result, some have recommended routine nutritional screening. These researchers compared two potential methods of assessing nutritional status in 311 hospitalized patients aged 70 and older: serum albumin, and the subjective global assessment (SGA), which classified patients as well nourished, moderately malnourished (5 percent weight loss with mild examination findings), or severely malnourished (more than 10 percent weight loss with marked findings) based on a history and examination. Discordance between albumin and the SGA was common. In fact, the ability of either measure to predict the other measure was only marginally better than chance. The authors conclude that they may each reflect fundamentally different clinical processes.

Fuhrer, R., and Stansfeld, S.A. (2002). "How gender affects patterns of social relations and their impact on health: A comparison of one or multiple sources of support from close persons." (AHRQ grant HS06516). Social Science & Medicine 54, pp. 811-825.

British men tend to receive most of their practical emotional support from their wives, whereas women obtain more support from female friends than their husbands. Yet both men and women have the same proportion of women among their closest friends. Previous studies have examined a person's social support only from the "closest person." Expanding the field up to four people provides a more accurate picture, and differences between men and women are weakened, if not eliminated, when this approach is used to predict physical and psychological health. The researchers asked British civil servants (aged 35-55 years) to complete questionnaires about social networks and social support up to a maximum of four nominated people they "felt very close to." Over 92 percent of the married/cohabiting men nominated their wives as the closest person in contrast to 80 percent of married women who nominated their partners. When nomination of a spouse was excluded, 64 percent of men and 59 percent of women nominated a woman as their closest person. About 9 percent of the men and 4 percent of women nominated only one close person, while 65 percent of men and 75 percent of women nominated four close people. Being in the group with the least cumulative emotional support increased the risk of ill physical and mental health for both men and women.

Macek, M.D., Manski, R.J., Vargas, C.M., and Moeller, J.F. (2002, April). "Comparing oral health care utilization estimates in the United States across three nationally representative surveys." Health Services Research 37(2), pp. 499-521.

There are three main sources of nationally representative dental visit data in the United States: the National Health Interview Survey (NHIS, which has long been the standard data source), the National Health and Nutrition Examination Survey (NHANES), and three health expenditure surveys from AHRQ: the 1977 National Medical Care Expenditure Survey (NMCES), the 1987 National Medical Expenditure Survey (NMES), and the 1996 Medical Expenditure Panel Survey (MEPS). These researchers compared dental visit estimates derived from the standard NHIS with estimates derived from NHANES and the health expenditure surveys to assess differences across surveys and stratum-specific trends within surveys. Sociodemographic, stratum-specific trends were generally consistent across surveys, but overall estimates differed. The researchers suggest that a validation study be conducted to establish true utilization estimates.

Reprints (AHRQ Publication No. 02-R071) are available from the AHRQ Publications Clearinghouse.

Reuben, D.B. (2002). "Organizational interventions to improve health outcomes of older persons." (Presented at AHRQ-supported conference). Medical Care 40(5), pp. 416-428.

This author points out that a variety of organizational interventions have been implemented to improve the health outcomes of older people. These range from comprehensive geriatric assessment and management of elderly patients to dedicated acute care hospital units. However, the evidence supporting the effectiveness of these interventions is inconsistent, they rarely reduce health care costs, and there have been formidable barriers to implementing successful interventions into practice. The researcher suggests several ways to overcome these barriers. First, the costs and benefits of such interventions must be clearly articulated so that health care systems will have better-informed decisionmaking. Second, Federal and national accrediting efforts to measure quality of care should be continued, but the measures need to be further tested and refined. Third, fee-for-service Medicare must provide incentives for improving the efficiency of health care delivery for the elderly.

Sohn, M-W. (2002, April). "A relational approach to measuring competition among hospitals." (AHRQ grant HS08002). Health Services Research 37(2), pp. 457-482.

This author presents a new relational approach to measuring competition in hospital markets and compares this approach with alternative methods of measuring competition. The author used patient discharge abstracts and financial disclosure files for 1991 from the California Office of Statewide Health Planning and Development to derive patient flows. The patient flows were combined to calculate the extent of overlap in patient pools for each pair of hospitals, producing a cross-sectional measure of market competition among hospitals. This relational approach produced measures of competition between each and every pair of hospitals in the study sample, which allowed examination of a much more local effect of competition. Preliminary analyses found that hospital markets were smaller than thought, for-profit hospitals received considerably more competition from their neighbors than either nonprofit or government hospitals, and hospital size did not matter in the amount of competition received.

Wolf, L.E., Croughan, M., and Lo, B. (2002). "The challenges of IRB review and human subjects protections in practice-based research." (AHRQ/NIMH MH42459). Medical Care 40(6), pp. 521-529.

This paper analyzes three challenges of Institutional Review Board (IRB) review and human subjects protections faced by Practice-based Research Networks (PBRNs): IRB review for clinician investigators who are not affiliated with the institution that has an IRB; multiple IRB reviews; and required training of key personnel in human subjects protection. The authors make several recommendations. Investigators should ensure that appropriate IRB review is obtained for all performance sites and plan for review for unaffiliated investigators. PBRN investigators and professional societies should educate IRB members and policymakers and publish articles about how IRBs might best address human subjects concerns in PBRNs. Finally, PBRN investigators need to ensure that their clinician investigators receive appropriate training in human subjects protection.

Zuvekas, S.H., and Cohen, J.W. (2002, Spring). "A guide to comparing health care expenditures in the 1996 MEPS to the 1987 NMES." Inquiry 39, pp. 76-86.

Substantial changes in the organization, delivery, and financing of health care during the past decade, combined with data collection and methodological improvement in the 1996 Medical Expenditure Panel Survey (MEPS), pose special challenges in comparing expenditure estimates in MEPS with those in the 1987 National Medical Expenditure Survey (NMES). The 1987 NMES used charges as its fundamental expenditure concept, whereas the 1996 MEPS used actual payments as its expenditure measure. In spite of these differences, researchers and policymakers want to be able to analyze trends in health care expenditures using these two surveys. Toward this end, the researchers present a simple, straightforward adjustment method that can be applied to the 1987 NMES public use expenditure data to improve comparability with the MEPS data. They provide several examples that illustrate the importance of the adjustments when analyzing trends in health care spending.

Reprints (AHRQ Publication No. 02-R076) are available from the AHRQ Publications Clearinghouse.

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Current as of August 2002
AHRQ Publication No. 02-0040

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