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Blacks are more likely than others to be hospitalized for asthma

Blacks are far more likely than people of other races to be hospitalized for asthma, according to the findings of a recent study by Peter J. Gergen, M.D., of the Agency for Health Care Policy and Research and his colleagues from the Medical Technology and Practice Patterns Institute in Washington, DC. According to the researchers, this finding holds true across all age and income groups and whether the asthma sufferer resides in a rural or urban area.

The study shows that in 1993 about half (56 percent) of 35,800 hospitalizations for asthma among nonelderly California residents were among blacks, Hispanics, and Asians. Blacks in each of four age groups (younger than 5 years, 5 to 19 years, 20 to 34 years, and 35 to 64 years) were hospitalized for asthma 4.6 to 6 times more often than whites, 2.5 to 3.8 times more often than Hispanics, and 2.7 to 7.3 times more often than Asians.

Overall, the hospitalization rate for blacks was four times higher than for others (42.5/10,000), but the reasons for this elevated risk remain unclear. In addition, Hispanic and Asian children under 5 years of age were at nearly twice the risk of hospitalization for asthma than same-age white children.

In general, only median household income and percentage of the population that was black significantly explained the geographic variation in asthma hospitalization rates across California. In each of the four age groups, regardless of race, asthma hospitalization rates were about 1.5 times higher for people residing in the poorest areas (median household incomes of less than $35,000) compared with those living in wealthier areas. Yet black children under 5 years of age in every income group were hospitalized 1.9 to 6.4 times more often than whites, Hispanics, and Asians. For the youngest age group, an area's asthma hospitalization rate increased by 3.6 percent for blacks and 1.6 percent for Asians with an associated 10 percent increase in the proportion of black and Asian residents.

While there is no known biological reason for the greater prevalence of asthma among blacks, it may be a surrogate for unmeasured discrimination, lower quality of care, and limited health care access. On the other hand, minorities and the poor tend to receive treatment at facilities that do not practice "state of the art" asthma care, notes Dr. Gergen. The researchers used 1993 California hospital discharge data to analyze asthma hospitalization rates across census areas in the State.

Details are in "Race, income, urbanicity, and asthma hospitalization in California," by Nancy Fox Ray, M.S., Mae Thamer, Ph.D., Bahar Fadillioglu, B.S., and Dr. Gergen, in the May 1998 Chest 113(5), pp. 1277-1284.

Reprints (AHCPR Publication No. 98-R070) are available from the AHCPR Publications Clearinghouse.

Socioeconomic barriers limit participation in diabetes education programs

Although little has been published about participation of Hispanic patients in diabetes education programs, a recent study supported in part by the Agency for Health Care Policy and Research (HS07397, Mexican-American Medical Effectiveness Research Center) suggests that Mexican-American patients are just as likely to attend diabetes education classes as non-Hispanic patients. Jacqueline A. Pugh, M.D., of the University of Texas Health Science Center and the MEDTEP Research Center in San Antonio, served as principal investigator for this study.

Dr. Pugh and her colleagues randomly assigned 596 patients with type-2 diabetes to a choice group (they chose their curriculum) or a no-choice group. Nearly 85 percent of study participants were Hispanic. Those in the choice group could select between a standard introductory diabetes education program (60 percent devoted to nonnutritional management practices and 40 percent to nutritional management) or one with an enhanced nutritional curriculum (60 percent of content). In the latter program, patients spent more class time on topics such as modifying the amount of fat and cholesterol in traditional Hispanic foods. Both programs included 5 weekly 2-hour classes.

Of the 305 patients given a choice, 78 percent chose the nutrition program. Patients given a program choice did not complete more classes than those without a choice (2.94 vs. 2.79 classes) and did not appear to be more satisfied with the classes. The most frequently reported reasons for nonattendance were illness (20 percent), inability to leave work (19 percent), family obligations or emergencies (19 percent), and transportation problems (16 percent). Despite the culturally sensitive approach of this program, the overall no-show rate was 30 percent.

Details are in "Patient choice in diabetes education," by Polly Hitchcock Noel, Ph.D., Anne C. Larme, Ph.D., Julie Meyer, M.S.N., and others, in the June 1998 Diabetes Care 21(6), pp. 896-901.

High blood pressure is a risk factor for preterm birth among pregnant black women

Preterm birth occurs in nearly 11 percent of all births in the United States, is much more common among black than white women, and is associated with 75 percent of newborn deaths not caused by congenital anomalies. Black women with hypertension are substantially more likely to deliver prematurely (prior to 37 weeks gestation) than black women with normal blood pressure, finds a study supported by the Agency for Health Care Policy and Research (HS07400).

Compared with the normotensive black women in this study, those with pregnancy-induced hypertension were almost twice as likely to have preterm births and those with chronic hypertension preceding pregnancy were more than 1.5 times as likely to do so. Those women whose chronic hypertension was aggravated by preeclampsia (a toxic condition that sometimes occurs in late pregnancy) were more than four times as likely to have preterm births.

Given the 2.5 times greater prevalence of chronic hypertension among black pregnant women as among other pregnant women, the contribution of chronic hypertension to the problem of preterm birth seems more serious than previously recognized, according to Aziz R. Samadi, M.D., M.P.H., and Robert M. Mayberry, Ph.D., of the Morehouse Medical Treatment Effectiveness Minority Research Center at the Morehouse School of Medicine in Atlanta, GA. Drs. Samadi and Mayberry analyzed hospital discharge records from the National Hospital Discharge Survey of black women with preterm births between 1988 and 1993 to determine the effects of maternal hypertension on spontaneous preterm birth.

The researchers also found that black women who had both chronic hypertension and genitourinary infection had nearly three times the odds of preterm birth as black women with chronic hypertension who did not have genitourinary infection. In contrast, the odds of preterm birth associated with pregnancy-induced hypertension among women with genitourinary infection were decreased compared with the odds among women with pregnancy-induced hypertension without genitourinary infection. In this latter group, the reduced odds of preterm birth may have been due to close monitoring and, in many cases, antibiotic treatment.

For details, see "Maternal hypertension and spontaneous preterm births among black women," by Drs. Samadi and Mayberry, in the June 1998 Obstetrics & Gynecology 91(6), pp. 899-904.

Certain factors improve satisfaction with prenatal care for low-income women

Low-income pregnant women appear more likely to be satisfied with the prenatal care they receive if procedures are explained by the provider, there are short waiting times for care, and ancillary services (especially substance abuse services and childbirth education) are available, says a new pilot study supported by the Agency for Health Care Policy and Research (HS08115). In addition, satisfaction appears to be increased when the prenatal care provider is male. Improved satisfaction with care has been linked to better use of health care services, and improved use of prenatal care services continues to be a key strategy for decreasing the incidence of low birthweight and infant mortality, explains Arden Handler, Dr.P.H., of the University of Illinois School of Public Health.

The researchers conducted telephone interviews in which 75 black and 26 Mexican-American women 18 years of age or older who were pregnant with their first child and had at least three prenatal care visits were asked about their prenatal care experiences, including their satisfaction with care. These women received care from a variety of providers. The researchers found that more than half of the women had more than a 30-minute wait at a typical visit. On the other hand, most spent more than 15 minutes with their practitioner during these visits and reported that the practitioner explained procedures, answered questions, and asked them questions all or most of the time. Yet less than one-fourth of the women reported that nutrition, social, and substance abuse services and/or childbirth education were available onsite.

As a group, women whose practitioners explained procedures all of the time (accounting for 32 percent of the variance in satisfaction), whose caregivers were male, who experienced a waiting time of 20 minutes or less, and whose site of care had four ancillary services available were twice as satisfied with care (satisfaction score of 88 vs. 43 percent) as were women whose practitioners never explained procedures, whose caregivers were female, who had a waiting time of up to 40 minutes, and whose site of care had no onsite ancillary services.

For more information, see "Health care characteristics associated with women's satisfaction with prenatal care," by Dr. Handler, Deborah Rosenberg, Ph.D., Kristiana Raube, Ph.D., and Michele A. Kelley, Sc.D., in Medical Care 36(5), pp. 679-694, 1998.

Community violence exacts a high emotional toll on urban black children and adolescents

Urban black children and adolescents who witness or are victims of violence experience some symptoms of post-traumatic stress disorder suffered by soldiers returning from war. Children exposed to violence are more likely than other children to suffer from intrusive and unwanted fearful thoughts or feelings. They may be easily distracted by fearful thoughts, sights, or smells that remind them of a negative incident. Many of these young people feel that they do not belong anywhere. These symptoms of emotional distress increase according to the number of violent acts the child has witnessed or been victimized by, according to a study supported in part by the Agency for Health Care Policy and Research (HS07392).

Researchers at the MEDTEP Center for Minority Health Research at the University of Maryland analyzed responses of 349 low-income black children (aged 9 to 15 years) in Baltimore to the Checklist of Children's Distress Symptoms (CCDS) and correlated distress symptoms with type and frequency of violence exposure. The average youth had been a victim of two violent acts; one in ten youngsters had been a victim of six or more violent acts. About 10 percent of the youths had been raped or threatened with rape, had been shot, or had been attacked with a knife. More than two-thirds of the youths had seen other people using or selling drugs, seen others arrested by the police, or heard gunfire. One-third had seen someone being shot, and nearly one-fourth had seen someone being killed. Young people who witnessed severe violence—including rape, suicide, and murder—were more apt to experience intrusive thoughts/feelings and to be distracted than those who had not done so. Youths who were victimized by or witnessed events that involved threats of or actual physical violence were more likely to feel that they didn't belong anywhere. The researchers suggest that schoolchildren be periodically screened to identify and help youths at high-risk for emotional distress from community violence.

See "Distress symptoms among urban African-American children and adolescents: A psychometric evaluation of the Checklist of Children's Distress Symptoms," by Xiaoming Li, Ph.D., Donna Howard, Dr.P.H., Bonita Stanton, M.D., and others, in the June 1998 Archives of Pediatric and Adolescent Medicine 152, pp. 569-577.

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AHCPR News and Notes

Researchers describe AHCPR's current and potential preventive services research agenda

As part of its mission, the Agency for Health Care Policy and Research supports studies that identify ways to increase the delivery and efficiency of recommended clinical preventive services such as immunizations, common screening tests, counseling to reduce health risks, and chemoprophylaxis to prevent disease. The U.S. Preventive Services Task Force (USPSTF), a Government-appointed expert panel, develops recommendations for primary care doctors on the appropriate content of the periodic health examination.

A recent article by James K. Cooper, M.D., and Carolyn M. Clancy, M.D., of AHCPR's Center for Primary Care Research, describes AHCPR's clinical preventive services research agenda. A second article by David Atkins, M.D., M.P.H., and Carolyn G. DiGuiseppi, M.D., M.P.H., of AHCPR's USPSTF scientific staff, describes some major areas where research is needed to define the appropriate use of specific screening tests, counseling interventions, immunizations, and chemoprophylaxis. The two articles are summarized here.

Cooper, J.K., and Clancy, C.M. (1998). "Health services research agenda for clinical preventive services." American Journal of Preventive Medicine 14(4), pp. 331-334.

As part of its research agenda for clinical preventive services, AHCPR has invited researchers to submit proposals to help translate disease-prevention knowledge into improved and more efficient clinical preventive services. AHCPR is interested in proposals that address efficacy-proven clinical preventive services, not research on preventive services for which efficacy has not been established. Research is sought in three interrelated areas—effectiveness and cost-effectiveness, quality, and access—and research projects may address one, two, or all three areas.

Cost constraints and movement toward competitive contracting for clinical services increase the need for reliable and acceptable cost-effectiveness data. Groups that purchase or pay for health care, such as corporations and purchaser alliances, need information on the effectiveness and costs of preventive services. Research interests in this area range from cost-effectiveness studies on specific preventive services, cost-effectiveness comparisons of practice standards and recommendations, comparing different methods for delivering preventive services currently suggested by various organizations, and the effects of various practice management patterns on the cost-effectiveness of clinical preventive services.

Research is needed to develop more meaningful and efficient methods for measuring and improving the quality of clinical preventive services. Specific quality issues include timeliness, appropriateness of technique or procedure, avoidance of harm from the service, and relevance of the technique or procedure to the recipient. Examples of particularly intriguing questions in this area include: What are the best measures of the quality of clinical preventive services? What is the comparative validity of patient reports, chart review, facility report cards, and/or claims data for different preventive services? How can quality-of-service measures be standardized for fair comparison? What are the best methods to ensure timely followup of abnormal screening test results?

Improved availability of preventive health care services is a generally agreed upon national goal. Economic barriers certainly may reduce the use of preventive services, and lack of knowledge (including education and physician recommendation) is another barrier. Reducing preventive service access barriers may require a comprehensive preventive health systems management approach to help determine the appropriate infrastructure and personnel needs for delivering clinical preventive services. Studies that examine the use of nonphysician providers for clinical preventive services are needed to determine if their use would increase capacity and preserve or increase access to preventive services. Technologic support—for example, a computer-assisted information management system—may increase access to clinical preventive services. Health systems management research can define methods for integrating computer techniques into a comprehensive health plan for delivering preventive services. Other useful research would include comparisons of technologic support in different managed care systems and identification of the organizational characteristics that improve the delivery of preventive services.

Reprints (AHCPR Publication No. 98-R074) are available from the AHCPR Publications Clearinghouse.

Atkins, D., and DiGuiseppi, C.G. (1998). "Broadening the evidence base for evidence-based guidelines." American Journal of Preventive Medicine 14(4), pp. 335-344.

These authors draw on their experience as scientific staff to the USPSTF to describe some major areas of research needed in preventive care. They give a high priority to determining practical ways to improve the quality of lifestyle counseling offered in the typical busy primary-care practice. They call for research to identify effective and practical primary care interventions for modifying personal health practices of patients, especially around issues such as diet, exercise, alcohol and drug use, and risky sexual behavior.

In the most recent USPSTF guide, many of the interventions still received a "C" recommendation, indicating that the USPSTF found insufficient evidence to recommend for or against providing them as a routine part of the periodic health examination. Based on their work in reviewing published scientific literature for a new edition of the guide, Drs. Atkins and DiGuiseppi have identified several key areas in need of further research. These include clarifying the optimal intervals for certain screening tests and counseling interventions and identifying practical ways in which patients can share in decisionmaking about preventive care, especially for services of possible but uncertain benefit.

They also call for research to examine the most sensitive and efficient ways to identify high-risk groups who may need different services than the average population, expand use of decision-analysis and cost-effectiveness analysis to help identify optimal use of clinical preventive services, and identify ways to reliably and effectively measure and improve the delivery and quality of preventive care provided in the primary care setting.

Reprints (AHCPR Publication No. 98-R086) are available from the AHCPR Publications Clearinghouse.

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Abstracts due by December 14 for Building Bridges Research Conference

The fifth annual Building Bridges Research Conference will be held April 12-13, 1999, in Chicago, IL. The Building Bridges Conference series, jointly sponsored by the American Association of Health Plans (AAHP), the Agency for Health Care Policy and Research, and the Centers for Disease Control and Prevention, is a collaborative initiative to bring together the managed care and health services research communities.

The theme of this year's conference is "The Health Care Puzzle: Using Research to Bridge the Gap Between Perception and Reality." Conference participants will have an opportunity to meet with leaders in health services research, academia, government, and managed care organizations on issues such as:

  • The role of health services research in educating policymakers and the public about the realities of managed care delivery systems.
  • How the effective use of data can bring about improvements in health care quality.
  • How perceptions of the media, health care providers, legislators, regulators, and the general public affect health care policymaking at the Federal, State, and local levels.

The conference planning committee is soliciting papers for presentation at concurrent sessions and for the poster program. The committee is particularly interested in papers that present quantitative and qualitative research findings on the following ten topics:

  • Population-based health issues.
  • Community leadership.
  • Evidence-based medicine.
  • Information systems.
  • Relationship between cost and quality.
  • Consumer information.
  • Influence of purchasers.
  • Women's health.
  • Medicare, Medicaid, and SCHIP.
  • Quality measurement and improvement.

Abstracts are due by December 14, 1998. Abstract submission forms and instructions are available in the preliminary conference brochure. To receive a brochure, contact Jan Liverance at AAHP, phone (202) 778-3222 or E-mail Or, you may access the brochure through AAHP Online ( or via AAHP's fax-on-demand system (using the handset of your fax machine, dial 888-AAHP-FAX, and request document no. 213).

For questions about abstract submissions or the conference, contact Jill Arent, Conference Coordinator, at (202) 778-3234 or

Call for abstracts on health survey methodology

The Seventh Conference on Health Survey Research Methods (CHSRM) will continue the series that began in 1975 to discuss new, innovative survey research methods that improve the quality of health survey data. The CHSRM, which is being sponsored by the Agency for Health Care Policy and Research, will bring together researchers from various disciplines who are at the forefront of survey methods research, are responsible for major health surveys, and/or use survey data in health policy research. The conference has been tentatively scheduled for late September or early October 1999 in a still-to-be-determined Northeast or mid-Atlantic State.

A call for abstracts has been issued for CHSRM. This call seeks abstracts for both original studies and overview papers that describe research beyond what is currently known about survey methods and their application to health-related issues using the following topics as general guidelines:

  • Populations of interest: the need for State and local data of national relevance (e.g., record linkage, comparability of data collection methods, privacy/confidentiality, small area estimation, rare populations, geomapping); collection of data from children and adolescents (e.g., consent, access, sampling frames, age-specific interview issues, multi-level analysis); racial and ethnic populations and cross-cultural considerations (e.g., national versus small area samples, language, identifying populations, interviewer effects).
  • Content and measurement: cost, access, and quality of care (e.g., appropriate populations and denominators, comparability across surveys, settings, sampling institutions, cost-benefit and effectiveness, alternative measures); assessment of consumer and patient perspectives (e.g., risk perceptions, patient utilities and preferences, expectations and experiences in receipt of care, satisfaction); collection of data on sensitive topics (e.g., consent, biomedical testing, ethical challenges, collection and banking of biological specimens, illegal behaviors such as abuse, interview modes, cooperation).
  • Data collection methods: comparability of data across different modes of data collection (e.g., questionnaire development, adjustments and weighting, combining modes to improve reporting on special populations); interactions between interviewers, respondents, and computers (e.g., process issues, usability testing, Web interviewing); substance use and abuse, including tobacco (e.g., as a barrier to care, validity of self-reporting, predictors of dependence, life course treatment, tracking users in outcomes studies, use of incentives); privacy and confidentiality (e.g., risk of disclosure, new laws for human subjects, record linkage, informed consent, multiple use of sampling frame, incentives as coercion); longitudinal surveys (e.g., tracking, cooperation, special population subgroups).

Attendance will be limited to approximately 80 individuals who will be invited to present papers, chair sessions, discuss presentations and the state of knowledge in specific areas, and serve as session recorders/reporters. Travel and lodging expenses will be covered for all non-Federal invited participants. To have a paper considered, send a 500- to 1,000-word abstract to Diane O'Rourke, Survey Research Laboratory, University of Illinois, 909 W. Oregon, Suite 300, Urbana, IL 61801 no later than December 4, 1998. For more information, call (217) 333-4273 or fax (217) 244-4408.

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Research Briefs

Grey, M., and Walker, P.H. (1998). "Practice-based research networks for nursing." (AHCPR grant HS09321). Nursing Outlook 46, pp. 125-129.

Nurse practitioners have described their practice as similar yet different from that of other primary care providers, but they have few hard data to support this conclusion. One useful approach to collecting these important data is a practice-based research network (PBRN). Such networks are not uncommon in medicine but are just coming into use in nursing, where more advances are needed, according to this commentary. The authors define essential components of PBRNs, provide examples of PBRN research, and discuss the applicability of existing networks to nursing. They point out that existing networks probably will not be able to accommodate the needs of primary care nursing studies. For instance, it is highly likely that the questions primary care nurses ask patients might be different than those posed by primary care physicians. Because existing networks are supported mostly by physician organizations, usually only physicians question patients.

Hlatky, M.A., and Owens, D.K. (1998, June). "Cost-effectiveness of tests to assess the risk of sudden death after acute myocardial infarction." (AHCPR grant HS08362). Journal of the American College of Cardiology 31(7), pp. 1490-1492.

Patients who have suffered a heart attack (acute myocardial infarction, AMI) have an increased risk of cardiac death for the first 6 to 12 months after hospital discharge. Many of these deaths are sudden and unexpected and presumably are due to cardiac arrhythmia. Studies suggest that the antiarrhythmic medication amiodarone is effective in reducing total deaths after heart attack. The authors of this editorial note the current uncertainty about the optimal approach to postinfarction testing to identify patients who would most benefit from amiodarone therapy. They point out that, in order to be confident about a test's ability to accurately measure risk of postinfarction death, more information is needed on the performance of tests such as heart rate variability in large, relatively unselected populations. In particular, researchers need to identify tests or test sequences that can detect patients at high risk of sudden death but at low risk of nonsudden death. It is in these patients that the antiarrhythmic therapy has the greatest potential to improve outcome.

McCoskey, S.K., and Selden, T.M. (1998). "Health care expenditures and GDP: Panel data unit root test results." Journal of Health Economics 17, pp. 369-376.

The relationship between national income (gross domestic product, GDP) and national health care expenditures (HCE) is a huge area of interest in health economics. Recently, researchers have begun to use panel data on HCE and GDP measured across countries and across time, which has several advantages. Using multiple years of data increases the sample size, and having multiple observations for each country enables researchers to include country-specific fixed effects. The use of panel data also raises a number of new issues, such as the presence of unit roots in the time series used to estimate the model. One group of researchers showed that if one examines the time series from each of the 20 Organization for Economic Cooperation and Development (OECD) countries separately, only rarely is it possible to reject the unit root hypothesis for either HCE or GDP. They suggest that panel estimates of the HCE-GDP relationship may be spurious. This paper discusses the question of unit roots in the OECD data, employing a recently developed unit root test that, unlike the country-by-country approach used by some, exploits the panel nature of the OECD data. Author Thomas M. Selden, Ph.D., of the Agency for Health Care Policy and Research's Center for Cost and Financing Studies, concludes that although no unit root test is likely to be definitive, the findings presented in this paper may help mitigate concerns that panel data analyses of national health care expenditures are inherently misspecified. Reprints (AHCPR Publication No. 98-R078) are available from the AHCPR Publications Clearinghouse.

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