Research Activities, June 2009, No. 346
Bergstrom, N., Smout, R., Horn, S., and others (2008, July). "Stage 2 pressure ulcer healing in nursing homes." Journal of the American Geriatric Society 56(7), pp. 1252-1258. Reprints (AHRQ Publication No. 09-R001) are available from the AHRQ Publications Clearinghouse.
Pressure ulcers, which affect many nursing home residents, form when constant pressure on an area of the skin (for example, due to being bedridden or in a wheelchair) reduces blood to the affected area and the tissue starts to die. These ulcers can become chronic gaping wounds that don't heal for months or don't heal at all. The researchers analyzed data on resident and wound characteristics associated with healing time of stage 2 pressure ulcers (abrasion, blister, or shallow crater) among 774 nursing home residents with a stay of 14 days or longer. Overall, there were 1,241 stage 2 pressure ulcers on 774 residents. Less than half (45.4 percent) of the ulcers healed. Median time to heal was 46 days. Median time to heal was 33 days for small (1 cm2 or less), 53 days for medium (greater than 1 cm2 and less than 4 cm2), and 73 days for large (greater than 4cm2) ulcers. The researchers found that nursing home residents' pressure ulcers that were large or located on the extremities were slower to heal than pressure ulcers located elsewhere.
Brokel, J. M., and Harrison, M. I. (2009). "Redesigning care processes using an electronic health record: A system's experience." (AHRQ grant HS15196). The Joint Commission Journal on Quality and Product Safety 35(2), pp. 82-92. Reprints (AHRQ Publication No. 09-R036) are available from the AHRQ Publications Clearinghouse.
This paper describes the steps taken by a multi-State Catholic health care system to implement a patient-centered electronic health record (EHR) in its hospitals and clinics. The authors discuss the planning and implementation processes, which were carried out at 32 facilities in 2 phases over an 8-year period for the health care system overall. An additional eight facilities will undergo planned EHR implementation by the end of 2011. Phase I consisted of a clinical data repository, dictated physician reports, pharmacy medication profile, and a set of adverse drug alerts. Phase II added computer provider order entry, decision support tools, emergency tracking, and medical records management. The authors describe a set of five principles used for the redesign of work flows, and summarize the lessons learned from the process.
Brown, T. M., Vaidya, D., Rogers, W. J., and others (2008, May). "Does prevalence of the metabolic syndrome in women with coronary artery disease differ by the ATP III and IDF criteria?" (AHRQ grant HS13852). Journal of Women's Health 17(5), pp. 841-847.
The metabolic syndrome, in which patients have a combination of high blood pressure, elevated blood glucose, abnormal lipid levels, and increased waist size (reflecting increased fat in the internal organs of the abdomen) is associated with elevated risk for heart attack or stroke. The researchers used data on 372 postmenopausal women to investigate the effect of using two competing clinical definitions of the metabolic syndrome on its prevalence and its usefulness in identifying women at high risk of future heart attacks or stroke. They compared the results using the criteria of 2002 National Cholesterol Education Program Adult Treatment Panel III (ATP III) with the results using the 2006 definition put forward by the International Diabetes Federation. Overall, women who met at least one of the definitions for the metabolic syndrome were significantly more likely to experience a cardiovascular event during followup than those who met neither definition (14 percent versus 6 percent). The researchers concluded that the 2006 redefinition does not improve the identification of postmenopausal women with demonstrated coronary artery disease who have the metabolic syndrome or improve prediction of their risk of heart attack or stroke.
Epstein, R. S., Frueh, F. W., Geren, D., and others (2009). "Payer perspectives on pharmacogenomics testing and drug development." Pharmacogenomics 10(1), pp. 149-151. Reprints (AHRQ Publication No. 09-R034) are available from the AHRQ Publications Clearinghouse.
As pharmacogenomic technologies move from the bench to the bedside, payer perspectives on pharmacogenomics testing and drug development become important. This paper describes payers' suggestions for data or study designs important for coverage determination of hypothetical drugs and pharmacogenomic tests. A workshop panel of representatives from the health plan, government, and employer sectors suggested seven areas for drug developers to strongly consider. These included comparative information on new tests versus usual care; assessment of the negative predictive value of new tests; measures and reports on cost offsets; balance of relative risk improvement with absolute risk; consideration of policy implications of the products or tests; reporting of percentage responders in addition to group mean improvements; and inclusion of specific pharmacogenomic information in U.S. Food and Drug Administration approved labels.
Field, S., Weiner, M., and Long, J. (2009). "Racial disparities in diabetes and physicians: Lack of association does not indicate cause or cure." (AHRQ grant HS17099). Archives of Internal Medicine 169(2), pp. 202-203.
The authors of this commentary criticize the statistical methods used by researchers who conducted a study of racial disparities in diabetes care that appeared earlier the same year in the same journal. The earlier paper concluded that few of the disparities in intermediate outcomes between black and white patients can be attributed to physician-related factors. The current authors suggest that the researchers' use of a random-effects model to evaluate physician-level factors was inappropriate and it would be better to treat these as a fixed effect using a conditional logit model. The conditional logit model does not have the same limitations as a random-effects model, and would give a stronger statistical basis for conclusions about physician effects.
Fiore, M. C., Jaen, C. R., and Baker, T. B. "A clinical practice guideline for treating tobacco use and dependence: 2008 update. A U.S. Public Health Service Report." (AHRQ Contract No. 290-06-0005). American Journal of Preventive Medicine 35(2), pp. 158-176, 2008.
The 2008 updated clinical practice guideline for treating tobacco use and dependence recommends brief and intensive smoking-cessation interventions and system-level changes to promote the assessment and treatment of tobacco use. An independent panel of 24 researchers supported by the Agency for Healthcare Research and Quality and 7 other Federal agencies analyzed new research findings since release of the 2000 guideline. Tobacco dependence is now viewed as a chronic disease that typically needs ongoing assessment and repeated intervention. Since 2000, evidence indicates that counseling, either by itself or with other treatments, is effective in helping patients (including teen smokers) quit tobacco use. Health care policies, such as health insurance coverage of tobacco-dependence treatment, increase the likelihood that a tobacco user will receive treatment and quit successfully. The 2008 guideline also cites areas in which additional research is needed, such as the development of innovative and more effective counseling programs. Research is also needed to develop more effective interventions for children, adolescents, and young adults.
Gardiner, J. C., Luo, Z., and Roman, L. A. (2008). "Fixed effects, random effects, and GEE: What are the differences?" (AHRQ grant HS14206). Statistics in Medicine 28, pp. 221-239.
Researchers need to understand the assumptions underlying the various statistical approaches available to them (the fixed-effects model, the random-effects model, and the method of generalized estimating equations [GEE]) to use the proper statistical method for analyses of repeated measurements taken as part of longitudinal studies. The authors of this paper describe the critical assumptions that researchers need to examine to determine which model is appropriate in a given setting. To demonstrate the differences in results obtained using each statistical model, the authors use a study of depressive symptoms in low-income pregnant women. The women were evaluated for depressive symptoms with a structured questionnaire five times, from before their child's birth to after birth. The findings using each statistical model are discussed, together with the reasons for differences in results.
Glance, L. G., Osler, T. M., Mukamel, D. B., and others (2009). "Impact of statistical approaches for handling missing data on trauma center quality." (AHRQ grant HS16737). Annals of Surgery 249(1), pp. 143-148.
A study on trauma center quality finds that using a multiple imputation technique to assign values to missing data results in quality measures nearly identical to those based on true data. The study used records from the National Trauma Databank for 63,020 patients at 68 hospitals with no missing quality data. When 10 percent of the quality data was randomly set to missing, quality rankings based on imputed data were virtually identical to the results obtained using true data from the databank records. Such measures gave inferior results, however, when patients with missing data were simply excluded from the analysis. Hospital quality assessment also changed when risk factors that had missing data were excluded.
Grant, R. W., Wald, J. S., Schnipper, J. L., and others (2008, September). "Practice-linked online personal health records for type 2 diabetes mellitus." (AHRQ grant HS13660). Archives of Internal Medicine 168(16), pp.1776-1782.
Clinicians sometimes do not intensify medications (strengthen the dose or add another medication) to better control the blood glucose levels of patients with diabetes. Uncontrolled blood glucose levels increase patients' risk of developing serious diabetes-related complications such as blindness and foot amputation. To learn if a Web-based personal health record (PHR) could improve diabetes care, the researchers randomized 11 primary care practices to a diabetes-specific PHR intervention or control. The diabetes-specific PHR imported clinical and medication data that the patient could correct or update, provided patient-tailored decision support, and enabled the patient to author a diabetes care plan to electronically submit to the doctor prior to upcoming appointments. Active control practices received a PHR to update and submit family history and health maintenance information. Overall, 244 patients (37 percent of those with registered online access) enrolled in the study. Most of the intervention and control patients had reasonable baseline blood glucose control. Nevertheless, markedly more patients in the intervention than control practices had their diabetes treatment regimens adjusted (53 vs. 15 percent).
Hinman, A. R., and Davidson, A. J. (2009). "Linking children's health information systems: Clinical care, public health, emergency medical systems, and schools." (AHRQ Contract No. 240-04-0014). Pediatrics 123(supplement), pp. S67-S73.
There exist a variety of children's health information systems, including immunization registries and other public health databases, trauma and accident registries (emergency services), school health information systems, and multipurpose health information exchanges. At present these systems do not connect with one another. The authors of this paper discuss the challenges and barriers-as well as the benefits-of developing a national, integrated health information system for pediatric patients. They discuss a demonstration project in Colorado, and conclude that technology is not the limiting factor. Instead, there is the need to include all stakeholders in defining the requirements of a linked system, develop implementation standards, and proceed through public-private sector collaboration rather than government dominance.
Khuri, S. F., Henderson, W. G., Daley, J., and others (2008, August). "Successful implementation of the Department of Veterans Affairs' National Surgical Quality Improvement Programs in the private sector: The patient safety in surgery study." (AHRQ grant HS11913). Annals of Surgery 248(2), pp. 329-336.
When the Department of Veterans Affairs implemented its National Surgical Quality Improvement Program (NSQIP) in all of its hospitals beginning in 1994, it resulted in a 47 percent progressive reduction in deaths within 30 days after surgery (postoperative mortality), and a 43 percent reduction in surgery-related illnesses within 30 days after surgery (postoperative morbidity). The researchers investigated whether the implementation of the NSQIP in private sector hospitals would have similar effects. Their study involved 184,843 patients who underwent major general or vascular surgery. Thirty percent of the patients in the study were from 14 private sector hospitals. They found that the implementation of the NSQIP in private hospitals over 3 years decreased their overall postoperative problems by 8.7 percent, surgical site infections by 9.1 percent, and kidney complications by 23.7 percent.
Lazarus, R., Klompas, M., Campion, F., and others (2009, February). "Electronic support for public health: Validated case finding and reporting for notifiable diseases using electronic medical data." (AHRQ grant HS17045). Journal of the American Medical Informatics Association 16, pp. 18-24.
U.S. physicians are required to report specific infectious diseases such as tuberculosis or HIV to public health authorities. However, existing manual, provider-initiated reporting systems generally result in incomplete, error-prone, and tardy information flow. This paper describes the Electronic Support for Public Health (ESP) application, which is an automated, secure, portable public health detection and messaging system for cases of notifiable diseases. The ESP application applies disease-specific logic to any complete source of electronic medical data in a fully automated process and supports an optional case management workflow system for case notification control. The ESP application has operated since January 2007 to apply rigorously validated case identification logic to ambulatory electronic medical record data from more than 600,000 patients.
Liu, L., Huang, X., and O'Quigley, J. (2008). "Analysis of longitudinal data in the presence of informative observational times and a dependent terminal event, with application to medical cost data." (AHRQ grant HS16543). Biometrics 64(9), pp. 950-958.
The authors of this paper propose a random-effects model of repeated measures, as are often taken during a longitudinal observational study. Their model deals with the presence of both informative observation times and a dependent terminal event (such as patient death). The random-effects model includes three submodels: a model for the intensity of recurrent hospital admission times; a random-effects model for the value of repeated measures; and a proportional hazards model for death. The researchers used correlated random effects to join the three models, and estimated the values via Gaussian quadrature techniques in SAS. When this procedure was used to model medical costs for patients with chronic heart failure seen in the University of Virginia Health System, the researchers found a significant difference based on the sex of the patient in the amount of medical costs per hospital visit. They also found that white patients had better outcomes than nonwhite patients, and that every 10-year increase in age raised the death rate by 91 percent.
Mayer, M. L., Skinner, A. C., Freed, G. L., and others (2009). "Interspecialty differences in the care of children with chronic or serious acute conditions: A review of the literature." (AHRQ grant HS13309). Journal of Pediatrics 154(2), pp. 164-168.
Prior research has shown that there are differences in the quality of care for adults with specific conditions among different medical specialists and between specialists and generalists. A review of the literature by the authors sought to determine whether this was also true for pediatric specialists and generalists. Although these researchers found differences in quality of care for children between pediatric specialists and generalists in all areas that they examined, the findings were not consistent enough to permit them to make overall recommendations about pediatric care delivery. Only studies of asthma-related care and surgical procedures consistently suggested a beneficial effect of specialty care. The researchers note that some conditions lack useful short-term outcome measures and are better evaluated using process measures (such as adherence to guidelines), while others are amenable to study of clinical outcomes, utilization, and cost.
M'ikanatha, N. M., Rice, D. H., and Altekruse, S. F. (2008). "Strategic use of state and local regulatory and public health surveillance resources to address the growing demand for food safety oversight in the United States." (AHRQ grant HS10399). Foodborne Pathogens and Disease 5(6), pp. 747-753.
The U.S. Food and Drug Administration is responsible for regulation of about 80 percent of the U.S. food supply. It provides oversight for more than 136,000 domestic food manufacturing facilities and warehouses that sell food across State lines and 189,000 overseas facilities that manufacture, process, pack, or store food sold in the United States. The authors of this study suggest that State-based food safety regulatory and surveillance systems should be better leveraged and integrated to complement the limitations of Federal measures. They recommend that a strengthened national food safety program include implementation of uniform standards of food inspection and testing, reciprocal acceptance of State and Federal inspection and laboratory findings, and systemic, timely sharing of data on pathogens recovered from contaminated foods and from ill persons.
Mielenz, T. J., Garrett, J. M., and Carey, T. S. (2008, May). "Association of psychosocial work characteristics with low back pain outcomes." (AHRQ grants T32 HS00032 and HS08293). Spine 33(11), pp. 1270-1275.
Most patients with low back pain will recover quickly from an acute episode, but about 10 percent become chronically disabled. The researchers evaluated the magnitude of the association between three psychosocial work characteristics (supervisor social support, coworker social support, and satisfaction with job tasks) with clinically relevant recovery outcomes 2 months after an acute episode of low back pain across various levels of biomechanical demands at work. The patients were 295 patients with acute low back pain seen by 31 primary care physicians in North Carolina. The researchers found that relative to patients with more social support from coworkers, those with less social support had 1.55 times the risk of not attaining complete recovery from low back pain 8 weeks later. Supervisor support and satisfaction with job tasks were not associated with clinical recovery. In addition, the biomechanical demands of the job did not modify this association.
Mutter, R. L., Rosko, M. D., and Wong, H. S. (2008). "Measuring hospital inefficiency: The effects of controlling for quality and patient burden of illness." HSR: Health Services Research 43(6), pp. 1992-2013. Reprints (AHRQ Publication No. 09-R011) are available from the AHRQ Publications Clearinghouse.
Studies that estimate hospital costs are sometimes criticized for not controlling for quality. In this study, the researchers employed controls for hospital quality and patient burden of illness to study data from 1,290 hospitals, using stochastic frontier analysis (SFA) to estimate hospital cost inefficiency and allow relative ranking of the hospitals. The study found that choices of controls for quality and patient burden of illness can have a nontrivial impact on the inferences derived from SFA about hospital economic performance. For example, using a single measure that combines a number of quality measures blurs insight into hospital performance and may prove misleading. In contrast, multidimensional measures of quality, such as AHRQ's quality indicators (QIs) show that different measures of hospital quality can have conflicting effects on hospital costs. The researchers note that, after controlling for hospital teaching status and patient burden of illness, quality outcome measures have little impact on average institutional cost inefficiency. For this reason, researchers using SFA to estimate overall hospital inefficiency may want to treat the resulting values as an upper bound.
Nutankalva, L., Wutoh, A. K., McNeil, J., and others (2008, July). "Malignancies in HIV: Pre- and post-highly active antiretroviral therapy." (AHRQ grant HS11673). Journal of the National Medical Association 100(7), pp. 817-820.
Since 1996, patients with HIV disease have found highly active antiretroviral therapy (HAART) beneficial. This therapy entails taking three to four antiretroviral drugs simultaneously to reduce the amount of the immune-system-damaging virus in the body. The researchers examined the prevalence of AIDS- and non-AIDS-defining cancers since the advent of HAART. They reviewed cancer diagnoses of 197 patients with HIV disease over a 13-year period that spanned the pre- (before 1996) and post-HAART timeframes to determine the effect of HAART on AIDS-defining cancers (ADCs) and non-AIDS-defining cancers (NADCs). Overall, 65 percent of cancers in both the pre- and post-HAART groups were ADC, and 35 percent were NADC. Among the 93 patients with cancer in the pre-HAART period, ADCs were more common (74 percent) than NADCs (18 percent). In the post-HAART period, ADCs accounted for 55 percent of malignancies, while NADCs claimed 50 percent. This upswing in NADCs may be due to improved diagnosis, the damage caused by HIV, side effects of HAART, or changes in the immune system that HAART causes, the authors suggest.
Pronovost, P. J., Goeschel, C. A., Marsteller, J. A., and others (2009). "Framework for patient safety research and improvement." (AHRQ grant HS14246). Circulation 119(1), pp. 330-337.
Researchers at Johns Hopkins University School of Medicine have developed a simple framework to identify effective patient safety efforts and offer strategies to put these approaches into practice. The five-part framework is also designed to help organize future patient safety research and address emerging issues. The domains in their framework are: (1) evaluating progress in patient safety; (2) translating evidence into practice; (3) assessing and improving safety culture; (4) identifying and mitigating safety hazards; and (5) evaluating the association between organizational characteristics and outcomes. In their report, the researchers identify as ongoing challenges the need to build capacity among researchers, create a research infrastructure, and evaluate the cost-benefit ratio of safety improvement efforts.
Sawicki, G. S., Smith, L., Bokhour, B., and others (2008, June). "Periodic use of inhaled steroids in children with mild persistent asthma: What are pediatricians recommending?" (AHRQ grant T32 HS00063). Clinical Pediatrics 47(5), pp. 446-451.
National asthma treatment guidelines recommend daily use of inhaled corticosteroids (ICS), which reduce the lung inflammation that makes breathing difficult, as first-line controller therapy for children with mild persistent asthma. The researchers surveyed pediatricians about their prescribing patterns for children's mild persistent asthma. More than 99 percent of the 251 survey respondents agreed that periodic ICS could be effective for some asthma patients. More than half (51 percent) said they prescribed daily ICS to most children with mild persistent asthma, whereas 31 percent said they recommended periodic ICS for these children. However, 18 percent of pediatricians prescribed neither daily nor periodic ICS for 50 percent or more of children with this problem. Pediatricians whose patient population was one-fourth or more black were 70 percent less likely to report prescribing daily ICS for mild persistent asthma. They were more likely to prescribe leukotriene modifiers for most children with persistent asthma.
Sharek, P. J., McClead, R. E., Taketomo, C., and others (2008, October). "An intervention to decrease narcotic-related adverse drug events in children's hospitals." (AHRQ grant HS13698). Pediatrics 122(4), pp. e861-e866.
Hospitalized children are harmed more often by prescribed narcotics than any other types of drugs. Efforts to reduce narcotics-related adverse drug events (ADEs) could greatly reduce overall ADEs at children's hospitals. The researchers analyzed data from 13 children's hospitals for 3 months before and 3 months after a 6-month implementation phase for at least 1 of 4 narcotic-related interventions: use of laxatives and stool softeners, limiting opportunities to override automated medication dispensing devices, implementing a standardized procedure for weaning children off extended prescription narcotic use to prevent withdrawal, and implementing consistent strategies to prevent narcotic-related ADEs during the transfer of children to other units in the hospital or their discharge from the hospital. Overall, the intervention program was associated with a significant 67 percent reduction in narcotic-related ADEs at the hospitals during a 3-month period after the interventions were fully implemented.
Wutoh A. K., Daftary M. N., Nwankwo A. E., and others (2008, July). "An analysis of antiretroviral adherence, resistance and HIV viral load: A pilot study." (AHRQ grant HS11673). Journal of the National Medical Association 100(7), pp. 867-868.
In a letter to the editor, the authors share the results of a pilot study that examined 11 patients' adherence to an antiretroviral regimen that included the drug nelfinavir and the patients' HIV viral resistance. When researchers performed baseline testing, they discovered that four patients were resistant to nelfinavir. The authors suggest that these patients were either infected with nelfinavir-resistant strains of HIV or developed this resistance because of antiretroviral therapy. Current guidelines encourage clinicians to perform resistance testing before making prescription decisions on antiretroviral drugs. This finding on nelfinavir confirms resistance typing's usefulness, the authors suggest. Though testing can be expensive (more than $400), it is usually covered by insurance and has an estimated cost-effectiveness ratio of nearly $24,000 for each quality-adjusted life year (QALY) gained. Health care treatments that cost $50,000 or less per QALY are considered cost effective.