Health Education Research Advance Access originally published online on November 5, 2007
Health Education Research 2008 23(5):803-813; doi:10.1093/her/cym062
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Who is providing and who is getting asthma patient education: an analysis of 2001 National Ambulatory Medical Care Survey data
1 Department of Family and Community Medicine, University of Illinois—Chicago College of Medicine at Rockford, Rockford, IL 61107, USA
2 Division of Environmental Health, Chicago Department of Public Health, Assistant Commissioner for Environmental Health 2133 W. Lexington Avenue Chicago, IL 60612, USA
3 National Center for Rural Health Professions, University of Illinois—Chicago College of Medicine at Rockford, Rockford, IL 61107, USA
* Correspondence to: M. N. Lutfiyya. E-mail: lutfiyya{at}uic.edu
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Abstract |
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Patient education in asthma management is important; however, there is little known about the characteristics of patients receiving asthma education or how often primary care physicians provide it. The objective of the study was to identify the characteristics of patients receiving asthma education. It was a cross-sectional study using 2001 National Ambulatory Medical Care Survey data. The study included 1230 physicians providing office-based ambulatory medical care in the United States. Patients in the study (weighted n = 11 279 952) were those diagnosed with asthma based on International Classification of Diseases, 9th Revision code receiving care from a pediatrician, internist or a family physician. Main and secondary outcome measures were asthma education ordered or provided. Multivariate analysis indicated that asthma patients receiving education were more likely to have office visits > 20 min [odds ratio (OR) = 3.934], be seen for an acute reason (OR = 2.268), be seen in follow-up rather than an initial visit (OR = 1.780), live in rural rather than metropolitan areas (OR = 1.507), have public rather than private insurance (OR = 1.276) and be seen in privately owned practices (OR = 1.248). Bivariate analyses indicated that patients seeing family physicians were more likely than those seeing internists or pediatricians to receive education. Patient education was not uniformly provided. Family physicians provided more asthma education than either pediatricians or internists. Future research should investigate the quality of education provided.
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Introduction |
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Asthma is among the most common chronic diseases and a disorder whose prevalence, morbidity and economic burden are globally increasing [1]. In the United States, approximately 1 in 10 people suffer from asthma [2] and a recent survey showed that each year among those with asthma about 1 in 10 require hospitalization, 1 in 4 visit the emergency room and about 30% make an urgent visit to their primary care provider [1]. To help address this growing problem, the National Heart, Lung and Blood Institute of the National Institutes of Health and the American Academy of Allergy, Asthma and Immunology publish treatment guidelines. A major component of these treatment recommendations is that clinicians provide appropriate education to their patients [3, 4]. Earlier, research has demonstrated that adequate patient education is clearly associated with improved outcomes in terms of asthma control [5, 6].
The push for asthma education is part of a larger movement for a patient-centered care model for chronic disease management that emphasizes the importance of coordinated care between the patient and the health care team. Over the past three decades, patient and public health education programs have been among the fastest growing components of health care in the United States [7] and are considered an important component of patient-centered care. The focus of these education programs is to promote a comprehensive agenda of disease prevention and health promotion [8] including physician-initiated patient education. These models improve outcomes for chronic illnesses, such as diabetes mellitus [9]. Patients rank it among the most important factors for their care [10].
Prior research in asthma education has focused on efficacy [11], relationship to cost of care [12], optimal methods of delivery [13] and health literacy [14]. Unfortunately, the evidence suggests that the educational needs for patients with asthma may not be adequately addressed [15]. However, there has been relatively little work done examining why asthma education is falling short of its intended goals. The purpose of this research was to determine the proportion of patients receiving asthma education and explore if disparities exist in the delivery of asthma patient education using data from the 2001 National Ambulatory Medical Care Survey (NAMCS). Identification of gaps in the distribution of patient education enables policy-makers to strategically target resources to specific groups in an evidence-based fashion. This study also examined what differences exist among three primary care specialties—internal medicine, pediatrics and family medicine—in how often they provided education to their patients with asthma. This is an important dimension to examine since the three primary care specialties see different groups of patients. Family physicians see patients across the life span and pediatricians provide care to children and internists to adults. This analysis should prove useful for developing initiatives to improve patient education for those with asthma.
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Materials and methods |
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The data for this cross-sectional study was extracted from the 2001 NAMCS, a nationally representative survey of physicians providing office-based ambulatory medical care in the United States. The 2001 NAMCS was conducted from 31 December 2000 through 30 December 2001 under the aegis of the Centers for Disease Control and Prevention's (CDC) Division of Health Care Statistics of the National Center for Health Statistics. At the time of the study, this was the most recent data that were available from the CDC in an analysable form. Respondents included both primary care physicians and specialists providing direct patient care in nonfederally employed office-based settings. Sample physicians were asked to complete Patient Record forms for a systematic random sample of approximately 30 office visits during a randomly assigned 1-week reporting period. For each visit, NAMCS collects information concerning the sociodemographic characteristics of the patient (age, race, ethnicity, sex), characteristics of the clinical practice, information about the treating physician, the clinic's geographical setting, process of care, sources of payment (including workers' compensation insurance), patient symptoms and diagnoses, medical and surgical services and medications provided and/or prescribed.
Study sample
The target population for the NAMCS includes all physician practices in the United States classified as providing ‘office-based patient care’ by the American Hospital Association and the American Osteopathic Association. The data collection methodology of the NAMCS has been previously described in detail [16–18]. Briefly, the NAMCS utilizes a multistage probability sample design involving samples of primary sampling units (PSUs), physician practices within PSUs and patient visits within physician practices. The 2001 sample included 1910 physicians, of whom 1230 (64%) participated in the study. The sample represented all 50 states as well as the District of Columbia. Once collected the data are weighted to be representative of the population being examined. As recommended by the CDC and the NAMCS, only weighted analyses were performed for this study.
Study variables
The analyses for this study included only those patients who had a diagnosis of asthma based on International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code, and had received care by a pediatrician, internist or a family physician. The dependent variable for this study was ‘asthma education ordered or provided’. In this survey, asthma education was defined as ‘information regarding the elimination of allergens that may exacerbate asthma, or other activities that could lead to an asthma attack or instruction on the use of a medication, such as an inhaler’ [19]. The independent variables included in the analyses were: patient sex, patient age, patient race, episode of care, reason for visit, physician specialty, payer source, amount of time spent with the physician, ownership of practice and geographic location of patient home address.
The variable geographic location of patient home address refers to whether or not the patient lives in a rural or a metropolitan area. The definitions for metropolitan and rural used in this study were based on whether or not the patient's address was located inside or outside of a metropolitan or micropolitan statistical area (MSA). Metropolitan and micropolitan statistical areas are geographic entities defined by the US Office of Management and Budget for use by federal statistical agencies in collecting, tabulating and publishing federal statistics. Those located within an MSA were considered to be urban or metropolitan patients and those outside an MSA were considered to be rural ones. These designations were made by the CDC [19] and were not changed for this analysis.
Statistical analyses
Variable factor coding and all analyses were conducted using SPSS 15.0 (Chicago, IL). To ease analysis and facilitate the interpretation of findings, some of the independent variables were recoded from those found in the original NAMCS database. This involved collapsing categories or removing missing data. All analyses were weighted, employing the weighted variable calculated and made available by the CDC. The weighted analysis allowed for drawing conclusions generalizable to the US population of interest.
Bivariate and multivariate analyses were performed. Bivariate analysis was conducted to determine if there were statistically significant relationships between the dependent variable and the independent variables by age groupings to differentiate pediatric and adult populations. Either an odds ratio (OR) as a measure of risk or a chi-square was calculated to test for statistical significance regarding the differences between independent variables and whether or not asthma education had been provided or ordered. An additional bivariate analysis was conducted to assess the impact physician specialty had on the provision of education to asthma patients by patient type (pediatric or adult). This additional bivariate analysis also examined the length of office visit.
Multivariate logistic regression analysis was performed to evaluate the unique association between each independent variable and the dependent variable while controlling for all other variables. ORs were calculated by the multivariate analysis to assess the relationship of each independent variable, holding all other independent variables constant, by the dependent variable—receiving asthma education. Because the estimates derived from our analyses are based on a sample rather than on the entire target universe of office visits, the results were subject to sampling error. To account for sampling effect, we report the 95% confidence intervals (CIs) around the adjusted ORs. This study received approval from the University of Illinois-Chicago College of Medicine at Rockford's Internal Review Board.
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Results |
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The mean age of the pediatric asthma patients in the sample population was 6 years and the mean age of the adult asthma population was 52 years. Sixteen percent of the pediatric and 12.7% of the adult asthma patient population was uninsured. In addition, 74.3% of the pediatric and 51.2% of the adult asthma patient populations had a primary care provider. Overall, 57.7% of all asthma patients received asthma education during office visits. When stratifying by age, 71% of pediatric (patients aged < 18 years) and 49% of adult (patients aged
18 years) asthma patients received asthma-related education (see Table I).
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Table II presents the results of a bivariate analysis of the independent variables by receipt of education stratified by patient population (pediatric or adult). For the pediatric population, Caucasian rather than non-Caucasian patients were more likely to receive education; the opposite was true of the adult population. A similar contrasting pattern emerged for payer source. For the pediatric population, those patients with public insurance were more likely to receive education, while for the adult population, the privately insured were more likely to. In addition, for the pediatric population, neither length of office visit nor patient's sex impacted receipt of education, while for the adult population both variables significantly impacted the dependent variable. Adults were also more likely to receive education at an initial visit whereas pediatric patients on follow-up visits. For both populations, receipt of education was more likely to occur during acute or chronic flare-up visits rather than chronic or preventive ones. Finally, both metropolitan adults and children were more likely to not receive education about their asthma.
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Bivariate analysis of provision of patient education by primary care physician specialty and length of office visit is presented in Table III. This analysis revealed that family physicians were more likely than internists (OR = 1.430, 95% CI = 1.428, 1.433) and slightly more likely than pediatricians (OR = 1.015, 95% CI = 1.007, 1.028) to provide education to asthma patients. When examining primary care specialty by the length of office visit where patient education was provided to patients with asthma, family physicians were more likely to provide education in visits lasting less than 20 min when compared with both internists (OR = 1.392, 95% CI = 1.388, 1.395) and pediatricians (OR = 1.276, 95% CI = 1.260, 1.292).
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Table IV summarizes the results of multivariate logistic regression analysis performed using asthma patients receiving patient education as the dependent variable. This analysis yielded that patients diagnosed with asthma and receiving asthma-related education had greater odds of spending more than 20 min with the physician during an office visit (OR = 3.934, 95% CI = 3.920, 3.948), seeing a physician for an acute or chronic flare-up rather than a chronic or preventive reason (OR = 2.268, 95% CI = 2.262, 2.274) and a follow-up rather than an initial visit (OR = 1.780, 95% CI = 1.775, 1.786). Asthma patients receiving asthma-related education were also more likely to live in rural rather than metropolitan areas (OR = 1.507, 95% CI = 1.495, 1.519), have public rather than private insurance (OR = 1.276, 95% CI = 1.271, 1.281) and be seen in a privately owned practice (OR = 1.248, 95% CI = 1.244, 1.252). These same patients had slightly greater odds of being non-Caucasian than Caucasian (OR = 1.005, 95% CI = 1.051, 1.060).
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Asthma patients not receiving asthma-related education had greater odds of being uninsured rather than privately insured (OR = .922, 95% CI = .917, .926), female rather than male (OR = .650, 95% CI = .648, .652) and
18 years of age rather than <18 years of age (OR = .294, 95% CI = .293, .295). |
Discussion |
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The NAMCS data, collected by the CDC, is a relatively untapped resource of nationally representative data. The results from this national survey indicated that educational disparities exist among patients with asthma [19]. Despite new treatment guidelines emphasizing patient education [3], it appears that many patients may not get education from providers about their asthma. Since patient education is a fundamental element of effective care [3–6], our results suggest that inadequate levels of physician education may contribute in part to health disparities related to asthma. Although some visits for asthma may not require an educational component, the variability in the percentage of visits with an educational component suggests that targeted interventions could increase the frequency of provider education.
Not unexpectedly, this study identified several factors associated with whether a visit was more likely to incorporate an educational component. However, it was somewhat surprising that among these factors individuals living in rural areas were more likely to receive patient education during a visit than those living in metropolitan areas. Historically, the emphasis on patient education has focused on urban areas because of increased asthma morbidity and mortality among urban minority populations [20]. Research conducted by Huss et al. [21] revealed that rural school nurses were less likely than urban school nurses to provide asthma education. Nonetheless, Weinberg [22] recognized that the need for asthma education in rural settings varies from urban areas but is just as important.
Our study differs from previous reports regarding asthma education [20–22] by finding that physicians in rural settings provided more education than their non-rural counterparts. This finding may reflect urban/rural trends in asthma such as a relatively lower prevalence of asthma in rural areas which could allow physicians to focus their efforts when they see asthmatic patients. It also could be that since more family physicians practice in rural settings, the greater prevalence of asthma education in such settings is a marker of where family physicians practice. In addition, the challenges of a busy urban practice may compromise educational interventions while the poorer access to specialty care in a rural setting may engender a greater responsibility for rural primary care physicians to render more comprehensive care. Finally, there may be greater physician awareness and compliance with asthma guidelines for those practicing in rural settings.
This study also revealed that adults were less likely to receive education than children. This may be because health care use is highest among the youngest children [23] and asthma is a leading chronic childhood disease [24] and a major cause of childhood disability [25]. Since the onset of asthma generally occurs in younger individuals, most adults with asthma have had previous doctor visits for asthma-related complaints and physicians may perceive adults to be more knowledgeable about how to manage their illness. In addition, older patients have fewer acute visits for asthma-related complaints which could also lead providers to believe that these individuals are less in need of patient education. However, asthma remains suboptimally controlled among adult patients and these results highlight the potential benefits of reinforcing the importance of asthma education for adult patients.
Another unexpected finding was the significant differences in practice patterns among family physicians, internists and pediatricians. Family physicians were more likely than either pediatricians or internists to provide asthma education to asthma patients. Although all of the primary care specialties embrace patient education, the emphasis that family practice training places on outpatient care and continuity might account in part for this finding. Additionally, differences in the patient populations served by the different primary care specialties might also account for our findings. Despite the similarities among primary care specialties, the disparities among them with patient education underscore the unique demands and challenges that each specialty faces. Our results suggest that disparities in the distribution of health care are perhaps more complex than previously perceived, and attempts for reform may require a unique, specialty-specific and population-specific approach.
Additionally, while it was not surprising that time spent with a physician has a striking impact on the receipt of patient education, family physicians were still more likely than either internists or pediatricians to provide education even in visits lasting 20 min or less. The average office visit is shorter than 20 min [26]. The higher level of patient education achieved by family physicians seeing similar patients to their primary care counterparts also supports the contention that there is room for improving physician-initiated patient asthma education.
Another finding was that patients seen for acute care were more likely to receive patient education than those being seen for chronic visits. Acute asthma attacks may be an indication that the current medication regimen is either inadequate or not being properly administered. Therefore, physicians may identify patients seen for acute flare-ups as being in greater need of patient education than those seen for routine follow-up visits. Additionally, reinforcing the need for education on preventing flare-ups could reduce the number of visits and improve overall asthma outcomes.
Considerable evidence exists that payer source influences the type and cost of care provided [27] and our results revealed an association with type of insurance and asthma education. We found that those patients without insurance were less likely to receive patient education than those with insurance. This is not an entirely surprising finding because patient education would be an additional service that physicians would be providing and would not be reimbursed for. Interestingly, those with public insurance were more likely to receive patient education than those with private insurance. There may be a perception among physicians that those with public insurance are in greater need of asthma patient education than other patients with asthma. Alternatively, this may reflect a greater desire to educate in hope of reducing visits that are likely to be poorly reimbursed. It might also be the case that those patients may have more severe disease or less control of their asthma. Future study to unravel the reason might be helpful in developing strategies to improve asthma education.
Our multivariate analysis also indicated that after controlling for payer sources and geographic location, non-Caucasians with asthma were slightly more likely to receive patient education than Caucasians with asthma. While the difference is a small one, it is an important one since hospital admissions for individuals of color have at times been almost 50% higher than for Caucasian patients [28]. It is possible that another variable related to race that has not directly been controlled for, such as patient income, is a confounding factor. Although the OR for non-Caucasians being more likely to receive asthma education was statistically significant, it was smaller than the ORs for other variables associated with receipt of patient education.
While this study detected differences in which patients were receiving patient education, in many instances our findings suggest that the right groups of patients were receiving more patient education. In other words, the differences detected did not always follow traditional lines of disparity. Nevertheless, female patients with asthma, asthma patients without insurance as well as adult patients with asthma were less likely to receive asthma education.
For each of the disparities identified, physician bias is a possible contributing factor. It has been documented through surveys of physician perception of asthmatic patients that physicians underestimate severity of disease and overestimate control [29]. Other underlying physician biases, such as which groups require patient education and counseling and which will benefit from it, are likely contributing to these disparities.
There are several limitations to this study. The data were collected in a survey of physicians, and is subject to reporter bias and a selection bias of those physicians who chose to participate. Although our analyses included a number of independent variables, it is possible that there are others that impact the distribution of patient education that were not included in the survey and hence not included in the analyses. This would include information about disease severity and disease control. Furthermore, it is possible that some of the patients with an ICD-9 code of asthma actually have another respiratory disease such as chronic obstructive pulmonary disease. Finally, the study did not examine the quality of education that was provided. For example, even though family physicians were more likely to provide education, it is quite possible that the quality of education they provided was not as comprehensive as their primary care counterparts. One physician could provide a 1-min cursory reminder on medication use while another could spend 45–60 min demonstrating the proper use of an inhaler, describing the differences between prevention and rescue medications, writing an action plan, and identifying environmental triggers. Due to the nature of the survey data used, a number of the aforementioned limitations could not be controlled for or avoided. However, future studies could collect information about the type of education provided and physician perception and its relationship to practice patterns. Additionally, future studies could be designed to better characterize the disparities that exist in the distribution of patient education and to answer the question of why these disparities exist.
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Conclusion |
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Patient education for patients with asthma still seems to be suboptimal in frequency and is not uniformly provided to patients. Older asthma patients, female asthma patients, and those asthma patients without health insurance were less likely to receive asthma education. Patients living in rural areas, having public rather than private insurance, and those seen for acute and longer visits had greater odds of receiving asthma education. In addition, family physicians rather than pediatricians or internists were more likely to provide education. Future study to establish goals for asthma education and assess the quality of education provided should be helpful for improving patient outcomes.
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Conflict of interest statement |
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TopAbstractIntroductionMaterials and methodsResultsDiscussionConclusionConflict of interest statementReferences |
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None declared.
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References |
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Received on May 2, 2007; accepted on August 10, 2007
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