| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Guest Access | Sign In via User Name/Password
|
|
|
|||||||
Guest Access | Sign In via User Name/Password |
|||||||||
* From the Department of Pediatrics (Dr. Cabana, Ms. White, and Ms. Heidmann), University of Michigan Health System, Ann Arbor, MI; Division of Pediatric Critical Care Medicine (Dr. Bratton), Department of Pediatrics, University of Utah, Salt Lake City, UT; and^Department of Health Behavior and Health Education (Ms. Valerio and Dr. Brown), University of Michigan School of Public Health, Ann Arbor, MI.
Correspondence to: Melissa Valerio, MPH, Department of Health Behavior and Health Education, School of Public Health, University of Michigan Health System, Ann Arbor, MI 48109; e-mail: mvalerio{at}umich.edu
Abstract
Objective: This article explores parental caregiver perspectives on barriers to asthma care in the Medicaid system.
Methods: Focus groups were held for parents of children with persistent asthma to identify barriers to asthma care for children insured by Medicaid in the Ypsilanti, MI area. Semistructured questions regarding health goals, asthma care, and access were used. Themes were defined as distinct categories or concepts regarding aspects of asthma care and coded.
Results: Thirty-six adults participated in four focus groups, 89% were the biological mother, and 64% were African American. Major themes identified included caregiver emotions, caregiver/patient knowledge, environmental issues, school/daycare support, Medicaid health-care system issues, the role of medical providers, and emerging adolescence. Parents demonstrated asthma awareness but were not confident in their role as the child’s disease manager. A specific gap was seen in the caregiver’s level of self-efficacy to control exposure to asthma triggers, monitor the child’s symptoms, and modify medications based on asthma symptoms.
Conclusion: Medicaid-insured families face unique barriers related to income and insurance limitations as well as issues common to others with asthma. Caregivers demonstrated a high level of asthma knowledge, but like other caregivers gaps between knowledge and behavior existed. Barriers to asthma care that may be specific to Medicaid-insured patients included difficulty maintaining continuity of care due to physician participation in Medicaid programs, and concerns about possible differences in asthma care from health-care providers due to their Medicaid insurance status.
Key Words: asthma • barriers to care • caregiver • Medicaid
Asthma is the most common chronic disease of childhood,1 and asthma prevalence in Michigan is higher than the national average.2 Strategies to alleviate the burden of asthma include health-care provider education and training to improve the use of clinical guidelines for asthma management and to improve health-care provider skills regarding asthma patient education, especially among high-risk patients.3
As part of the development of an educational program for physicians targeted to high-risk asthma patients, we conducted focus group sessions among parents of Medicaid-insured children with persistent asthma. It was important to include the perspective of this group on asthma care because asthma is more prevalent among economically disadvantaged children and they have high risk of hospital admission for asthma.4567
Medicaid insurance is both a surrogate for low income and a method of payment that contains financial incentives.8 The groups allowed us to better understand how parents care for a child with asthma insured by Medicaid and deal with system barriers to asthma care. By incorporating this information from this group of parents into our educational program for physicians, we believe that physicians can gain a better understanding of the parents’ unique barriers and important perspectives on asthma care.
The qualitative approach was utilized to elucidate and better understand parents’ experiences with the Medicaid program. Many quantitative studies have reported on Medicaid and health-care utilization,91011 quality of care,12131415 or asthma medication use or nonuse,1617 but these studies have not captured the dynamic interpersonal and intrapersonal experiences of parents: the personal interaction with Medicaid program staff, issues with coordination of appropriate asthma care in a health-care or educational system, and the internal feelings or parental perceptions of such challenges.
Our objective was to define important issues for children with asthma and Medicaid insurance. By understanding these issues, providers can better help patients and families manage this chronic condition and address unanticipated ways in which Medicaid insurance may affect their ability to successfully do so.
Materials and Methods
The participants were a convenience sample of 36 parental caretakers of 6- to 16-year-old children with (1) an asthma diagnosis, and (2) currently or previously enrolled in the Michigan Medicaid Health Management Organization/System. Eligibility was limited to parents or legal guardians of children 6 to 16 years of age with persistent asthma. Persistent disease was categorized using the National Asthma Education and Prevention Program asthma diagnosis and care guidelines18 and was defined as follows: asthma symptoms at least every other day during a 1-month period, 
2 nights of sleep interrupted in a month, daily asthma medications for at least 30 consecutive days, or 5 days of missed school due to asthma symptoms. The University of Michigan Institutional Review Board approved the study prior to identification and enrollment of study participants.
Patients were recruited from the University of Michigan Health System. Those who received asthma-related care from the Family Practice Clinics within the past year, lived in the Ypsilanti, MI area, and were insured by Medicaid were identified. Letters informing parents of the study objectives and procedures were mailed to their homes. Parents were then contacted by telephone to determine eligibility, request participation, and collect key demographic information. All efforts to recruit both male and female primary caregivers were made; unfortunately, only one male parent participated in the groups. Parents of children with additional chronic medical conditions such as diabetes, sickle-cell anemia, or lung-related conditions were excluded from the study.
Four focus groups were held at the Ypsilanti Health Department. Child care was provided during the group session and was coordinated by a child life therapist. Dinner for the children and parents was served, and parents received $50 compensation for time and transportation to the meeting. The goal was to recruit 8 to 10 parents for each focus group.
The moderator’s guide was designed to elicit conversation and evaluation of barriers to asthma care for children with persistent disease insured by Medicaid. The research team, including a pediatric pulmonologist and a respiratory therapist asthma educator, developed 13 prepared questions and prompts. The questions were based on a review of the literature with a focus on health goals, asthma care including environmental factors, medications, school support, family support, and issues relating to access to medical care. A content review of the questions was conducted by a pulmonologist and two pediatricians.
The focus group sessions were lead by two experienced facilitators (associated with the University of Michigan) who were present for all discussions applying a format outlined by Krueger.19 The groups were conducted in a manner to ensure anonymity, minimize group pressure, and encourage honest and spontaneous discussion. The moderators listened carefully to the participants and sought clarification of verbal and nonverbal responses, and asked participants to verify summarizing comments. Follow-up probe questions were asked to encourage and maintain discussion of topics. The moderators discussed and summarized each group discussion immediately after the gathering.
The 2.5-h sessions were recorded and transcribed verbatim. A study member using the audiotapes to ensure transcription accuracy reviewed the transcripts. Formatting for individual comments on the transcripts was included. This allowed for classification and facilitator comments as well as identification and blocking out of unrelated conversation and questions.
Analysis
Parents completed a demographic questionnaire (income, age, education) prior to the start of the focus group. Descriptive information for parents and children are presented using summary statistics (Table 1
). The focus group transcripts were coded line by line20 for distinct themes. Themes were defined as distinct categories, concepts, or ideas regarding aspects of asthma care using software (Nudist 5; QSR International Pty. Ltd; Melbourne, Australia). Categories were developed, and the transcripts were coded independently by two sets of coders who did not attend the focus group sessions: one pediatric pulmonologist, and a team of one respiratory therapist plus another study member. The two raters met to resolve coding differences between categories and subcategories of barriers. Interrater reliability for the categories was assessed using 
statistic with the overall (four groups) proportion of agreement (
0 = 0.96).
|
Four focus groups were held between December 2001 and January of 2002, including 35 women and 1 man. Primary care providers were self-identified as the biological mother (89%) and were most commonly in the age range of 25 to 35 years (50%). The majority of participants were African Americans (64%), and 31% were married. Participants reported an annual income range of < $10,000, with only five participants with an income > $30,000/yr. The median level of education for the participants was 13 years.
The children of the focus group members had a median age of 10 years. Forty-seven percent experienced frequent daytime asthma symptoms occurring daily or several times a week. Children missed a median of 8 days of school during the first half of the current academic year. Only four caregivers reported an asthma specialist managed their child’s asthma. All children were prescribed some asthma-related medication. Ninety-seven percent received an inhaled ß-agonist. Fifty percent reported taking a leukotriene inhibitor, and 47% reported inhaling corticosteroids. Almost one third reported taking oral steroids within the last year.
When discussing "how asthma affected their child’s life and health," the following domains were prominent: caregiver emotions, caregiver/patient knowledge, environmental issues, school/daycare support, Medicaid health-care system issues, role of medical provider, and emerging adolescence. Each of the domains is discussed with representative parental quotes.
Domain 1: Emotive
Parents often cited feelings of nervousness, frustration, anxiety, fear, or anger concerning their child’s asthma. Parents differed in how they tried to cope with these emotions. Some sought to overcome feelings of fear about their child’s asthma therapy and care by adoption of a care "routine." Parents who either had to deal with a child who required continuous asthma care or those who had cared for a child with asthma for a longer period of time appeared to have better mastered their fears: "I’m so used to it now, I just tell him to get on his asthma machine, and just calm down and usually he’s all right." Others remained stressed or overwhelmed by their child’s asthma: "I get nervous, I’m still not used to it, so I run to the doctor a lot. I don’t know if I’m giving too much medicine, the right medicine. You know, sometimes they treat me like I ought to know but I don’t know!"
Unfortunately, some parents did not have asthma management plans, which provided them less support to deal with their child’s illness and their fears. Some parents expressed low self-efficacy in execution of management strategies needed to treat their child’s symptoms. The caregiver’s emotions appeared to play an important role in the delivery of asthma care but could be positively affected by a supportive relationship with the medical provider.
Domain 2: Caregiver/Patient Knowledge
Whether or not caregivers had received asthma education, they expressed a desire for continuous educational information on medications, asthma triggers, and symptoms. Caregivers were aware of appropriate care strategies including attempts to recognize signs of worsening symptoms and when to seek acute care. Likewise, instruction for proper use of medical equipment was needed: "But when you say asthma treatment, it is also asthma education, you know what I’m saying? Like when you’re released from the hospital someone brings over a breathing machine, says this is how you work it and goodbye, good luck! That’s it!"
Parents also voiced the importance of gaining knowledge of medication side effects, such as their impact on the child’s weight gain and hyperactive behavior. Parents of children who were obese or overactive most often referred to medication side effects. Parents who felt more at ease and adopted a care "routine" also verbalized the importance of recognizing triggers, early onset of asthma symptoms, and the importance of remaining calm while providing care for their child.
Domain 3: Environmental
Most caregivers were aware of the potential effect that environmental triggers such as smoke, pollen, smog, stress, pets, household chemicals, and allergies can have on a child, and the majority said they had adopted indoor environmental changes in their households to avoid an asthma episode or symptoms. This awareness was attributed to physician care and education made available to parents.
Although parents have learned methods to diminish the effects of environmental triggers, they continued to experience situations that were beyond their control. These included exposures at friends’ or relatives’ homes.
"We couldn’t even go to restaurants because they have part of it [where] you smoke [and] one part you can’t. So no matter what, if you’re in there... smoke is in the environment and the child gets sick. And [if] you complain about it, well it’s not a smoke-free environment." Smoke-free restaurants and public locations continue to be a challenge for parents of children with asthma. Many believed community education of environmental triggers of asthma would assist in eliminating exposure and improving the family and child’s quality of life.
Domain 4: School/Daycare Support and Work
"The problem I had like S— said, the school leaves it up to your child to be responsible. That’s a kid. You can’t leave it up to them." The level of asthma support and knowledge at schools experienced by caregivers varied greatly, as did their experiences with institutional willingness to support children with asthma. This variable asthma support angered some parents who believed they were required to justify the child’s school absences and were questioned by schools for keeping their child at home in bad weather or at signs of worsening symptoms. Parents also reported a lack of school nurses, which they believed impacted the ability of the school to administer asthma medication care.
Parents voiced need for use of asthma action plans at schools. Parents who had received an asthma action plan from their physician thought it would also be a helpful tool for asthma management at the school, providing the child’s specific asthma care instructions. Some parents were strong advocates at the school and had provided asthma information and initiated conversations about the needs and abilities of their child to self-medicate.
Caregivers addressed the impact of their child’s asthma on their employment. Parents expressed the need for care throughout the day, knowing that they were unable to monitor their child 24 h/d. Appropriate management strategies for monitoring of their child’s asthma, including peak flow readings, were utilized by some parents in adjusting medications as needed in the mornings and evenings to avoid problems during the work day.
Domain 5: Medicaid Health-Care System
Experiences with the Medicaid system and personnel varied, while some caregivers mentioned no complaints, others believed they were discriminated against or frustrated by paperwork and changing coverage. Physician or specialist referrals were cited by parents as a barrier to acquiring proper asthma care. An additional barrier to ensuring good asthma care for children was the limitations set on refills by insurance. Caregivers believed it would be easier to manage their child’s asthma if they were able to receive multiple inhalers: one for school and another for home. Likewise, they need to be allowed to refill medications that were lost prior to the Medicaid 30-day refill cycle.
A concern for parents was the use of generic drugs. There was a general mistrust of generic drugs by parents who participated in the groups. For these parents, it was a matter of choice, being able to decide if they would use a generic over a brand-name medication.
Some caregivers reported completing monthly paperwork in order to maintain their Medicaid coverage. This was not only time-consuming, but difficult for the parents to coordinate in a timely manner to maintain care coverage while managing a household and caring for other children. Continuity of coverage was also difficult for parents to coordinate due to changes in physician participation with Medicaid or changes in patient insurance coverage.
Parents related that Medicaid should allow children with chronic conditions to have extended coverage. Changes in Medicaid coverage were sometimes a revelation to parents. Physicians or their office staff were often responsible for providing coverage information. A child’s asthma care may also require supplies that are costly for parents who understand their role in providing proper asthma care for their child, but could not afford them. Parents voiced willingness to learn more about the Medicaid system, to better maneuver and advocate for their child’s care, but were unsure where to get such information.
Caregivers expressed a concern that care provided differed when physicians or medical staff noted their Medicaid insurance coverage. Some had to show extra paperwork at the physician’s office, while others believed they received lesser treatment or were stigmatized. Overall, parents believed that coverage provided by Medicaid was adequate and that the needed care was available for their child. Medicaid was credited by some parents as allowing them to establish a medical home for their child’s asthma care.
Domain 6: Role of Medical Provider
Caregivers of children with asthma were concerned with the level of access to medical providers during an asthma episode. Availability of 24-h call lines during an emergency were seen as strategies to receive support prior to visiting an emergency department. Parents were concerned the level of office triage for asthma was either missing or of a lower priority, specifically during an asthma episode. Again, perceptions of discrimination and indifference were mentioned as issues for parents of children receiving care insured by Medicaid: "Or you are not going to get the full care that you would if you had regular insurance."
Caregivers noted the importance of physician verbal and nonverbal communication skills. Good relationships were those in which medical providers were characterized as good listeners and educators, willing to spend time with both the caregiver and child with asthma. The caregiver’s perception of the relationship appeared closely tied to their understanding of asthma management and their follow-through with care: "I just feel that the doctor letting me know everything that I need to know that can trigger the asthma helps."
Poor relationships were seen as those where medical providers not only spent little time with the caregiver and patient, but where asthma information was not clearly explained or messages were inconsistent. Periodically, parents received inconsistent asthma messages and education from within the provider’s office—physician vs nurse vs educator—staff.
Parents viewed their medical provider as their main source for asthma education. Some caregivers believed they needed asthma education beyond that provided by their physician, while others believed the physician and staff were in greater need of the asthma education. Several caregivers were very satisfied with the level of support and coordination of asthma care in the physician’s office. Successful medical provider approaches were multidisciplinary, including a physician staff team approach to the delivery of asthma care and education.
Domain 7: Adolescence
As "she got older she came to me, she said ‘Mom, I’m tired of taking all this medicine. It’s nasty, I’m just tired’. And we went through a phase where she was half taking her medications." An unanticipated issue that surfaced from parents was the need for support and age-appropriate asthma education for teenaged children. Caregivers reported a change in their ability to properly manage their child’s asthma during this transition from adolescent to teen. In younger children, parents were better able to oversee activities, adhere to medication schedules, and avoid exposure to environmental triggers. We found that with teenage children the impact of peer pressure and the need for belonging was not only evident but directly impacted the child’s adherence to their asthma management. The feelings of invincibility and embarrassment experienced by teenagers toward their asthma care routines were difficult for parent’s to penetrate even when the child fully comprehended the severity of their disease.
Several parents stated their teenaged child had experienced with or started smoking. They wanted medical input to deter such behavior that would worsen their child’s asthma. This domain requires further qualitative and quantitative exploration with parents/caregivers and teenagers.
Discussion
Parents in these focus groups of Medicaid-insured children with asthma, conveyed profound concern about the health of their children, but frequently felt unable to control or manage all circumstances that affected their child’s asthma. The role of the caregiver’s "feelings" or self-efficacy,21 the belief in one’s ability to successfully perform a task/behavior, appeared to directly influence management of the child’s asthma and reduce its impact on daily life. Self-efficacy impacts behavior and motivation necessary for managing a child’s asthma and care. The management of asthma requires coordination and awareness of multiple tasks. This may impact the caregiver’s self-efficacy at both behavior specific and situational (environment)-specific levels. In other words, a parent with lower self-efficacy may not be able to act or trust their capability for dealing with and caring for their child’s asthma in the Medicaid or medical systems. Our findings suggest that the caregivers require and desire ongoing education with an emphasis to support development of parental confidence regarding asthma self-management skills; feedback and communication may be able to address this.
Medicaid-insured parents looked to their physician to provide education for asthma management and generally related favorable opinions of the asthma care. This is similar to opinions reported by Anarella et al,12 who surveyed Medicaid recipients in New York and > 90% reported they were satisfied "overall" with their asthma care, and Medicaid-insured children in five managed-care organizations.10 However, only some of the focus group parents used self-management tools such as asthma action plans and peak flow meters to monitor and modify their child’s disease management program.
Parents recognized their own role in helping to manage their child’s asthma, but voiced concerns regarding their knowledge and judgment. Some of our caregivers reported receipt and use of an asthma action plan but often believed their skills were inadequate to execute the plan. The effectiveness of parental asthma education requires frequent physician assessment of caregiver’s home management strategies. Review of the patient’s home asthma plan allows physicians to detect both appropriateness of care and the caregiver’s asthma knowledge.2223 This review of strategies could serve as a mechanism to boost the caregiver’s self-efficacy and provide additional support once they have made appropriate asthma-related decisions for their child.
In order for families to be compliant with antiinflammatory care, they need to understand proper use of such medications, have their questions regarding potential undesirable side effects addressed, and believe (outcome expectancy) that administering this chronic medication to their child will decrease asthma symptoms and improve health.2224 When providers communicate this information well, patients use fewer acute care services and miss less school.72526
Like all children, these Medicaid-insured patients spend at least 6 to 8 h/d at school. The children are dependent on the school system to provide supervision and care for their asthma, which is a reasonable point of concern for parents.27 Many states including Michigan have policies that allow students to carry their own medication and self-medicate as necessary. A lack of awareness by teachers and school personnel of asthma was frustrating for the focus group caregivers. To tailor asthma care for children, physicians need to be knowledgeable of school-related care issues and assist families with school advocacy and asthma education.
As children develop, they become more independent and need more control and responsibility for their asthma management. A need for age-appropriate asthma self-management education was identified by the focus group parents to allow teenagers to better understand the disease and its management and to cultivate appropriate health beliefs to carry into adulthood. Understanding the developmental changes with teens such as peer pressure to smoke or be exposed to secondhand smoking is important for health professionals to address. Asthma requires long-term management skills and the ability to self-regulate, observe, judge, and react,28 to their asthma. Well-educated parents may help teens transition more smoothly to self-management.
Finally, a distinctive barrier was the parental perception on differences in quality of care, due to the use of Medicaid insurance. In some cases, parents believed that certain limitations (ie, the prescription of generic vs brand name medications, poor access to administrative assistance, limits on refills) were due to the fact that they had Medicaid insurance, as opposed to limitations imposed on both Medicaid-insured and non–Medicaid-insured patients. If this is an unstated concern of parents, it may be important for physicians to specifically state that their decisions for care are not based on the type of patient insurance. One technique to improve this would be to focus on communication, reassuring patients about any concerns or fears.
Many specific asthma and management challenges faced by Medicaid caregivers are not fundamentally different than those of other parents; however, they often have less social support to aid them in dealing with their child’s medical needs and face greater financial barriers compared to other parents. Our participants reported similar issues related to school, family quality of life, and financial issues as reported by Mansour et al27 in a study of urban, low-income families; however, they appeared to have greater asthma knowledge and voiced understanding that children with persistent disease required chronic anti-inflammatory therapy.
Issues identified by Fredrickson and colleagues29 in rural areas and cities in Kansas regarding preferences in asthma care delivery, provider communication, and difficulties in continuity of care were also noted in this population, but again our group participants presented a greater understanding of asthma care and management needs. Of interest is the role of the caregiver’s internal locus of control in asthma management. The comments elicited during the group sessions point to a lack of internal locus of control and a strong external locus of control. An individual with external locus of control believes that his or her situation is guided by external circumstance and not by their own behavior.212830 A sense of helplessness was evident in some of the participants’ statements, along with the belief that they needed additional assistance to manage their child’s asthma, tying into the role of self-efficacy in asthma management. This external locus of control may be a result of not only a lack of self-efficacy, but past experiences with the health-care system, providers, and Medicaid insurance.
Conclusions
Asthma self-management education should be targeted to improve control among high-risk populations.3 Medicaid-insured families face unique barriers related to income and insurance limitations as well as other issues faced by non–Medicaid-insured children with asthma.
The Medicaid-insured caregivers in our sample demonstrated a high level of asthma knowledge, but like other non–Medicaid-insured caregivers there are gaps between knowledge and behavior. A specific gap was seen in the caregiver’s level of self-efficacy to control exposure to asthma triggers, monitor their child’s asthma symptoms, and know how to change medications when their child’s asthma symptoms change, all of which impact compliance with asthma management strategies. Primary care physicians can support such patients and their families by moving beyond "one-shot" education initiatives to the provision of serial asthma education, targeting the reinforcement of home management strategies, appropriate asthma monitoring and treatment decisions, and openly discussing parental concerns regarding asthma care.
There were barriers to asthma care that may be specific to Medicaid-insured patients regarding difficulty in maintaining continuity of care and perceived differences in asthma care from health-care providers or medical staff. As a result, it may be helpful for physicians to employ strategies that demonstrate to patients that decisions for care are not based on the type of patient insurance, such as Medicaid insurance.
Appendix
Caregiver Comments per Domain
Domain 1: Emotive
"Just like scared because he can stop breathing on the way to the hospital when we are in the car... I got frustrated and hung up the phone and drove back to the hospital, and by that time she stopped breathing and was blue and I ran in and I was just like, help me! my baby’s not breathing!"
Domain 2: Caregiver/Patient Knowledge
"I would say being constantly aware of... you know, you like, you kind of keep your eye on them, don’t wait until its gotten so bad that you can’t... you know, like always checking in."
Domain 3: Environmental
"The care of the physician. I mean they actually talked to me and let me know what I should avoid, what she shouldn’t be around, and it’s very hard because her father is a smoker. And when she goes to visit him, I have to make sure she has everything... I mean you have to monitor your heat, I mean everything can affect them, so you just have to... "
Domain 4: School/Daycare Support and Work
"If my son is sick, just the mildest cold, I will keep him home from school because if I send him to school he’s going to end up in the hospital that day. But if I send him to school with a little bit of wheezing, that wheezing is going to turn into a lot of wheezing, and then he’s going to end up in an emergency room and five or six days in the hospital... . "
Domain 5: Medicaid Health-Care System
"Medicaid is always changing and switching plans, or one doctor doesn’t take it and this one will. You’re constantly switching different physicians and having to go through the whole history... "
"Basically like they were saying, you know, just some of the politics too, just how they make you feel sometimes. I mean it’s like I got leprosy or something. But really I mean when your child is sick, you don’t feel like going through all of that right there. And it’s like you’re in [a discount store] or something, ‘We have Medicaid’ and a person should not be made to feel like that... "
Domain 6: Role of Medical Provider
"My clinic is... I mean it’s been basically good, filling our needs, but I was not educated and after a while I realized that it was really adding to my frustration. I finally had to say to the doctor, we need more! She said it back to me in medical terms, ‘Yes, blah, blah, blah, sufficient diagnosis –whatever’. So then they started—beefed up the medication and taught me how to use the peak flow and ordered the nebulizer, and then I started feeling a little more secure."
Acknowledgements
We thank the parents and primary care providers who participated in the focus groups as well as Ms. Julie Piazza (Child Life Specialist) and the Ypsilanti Community Health Center that hosted the sessions. Special thanks to Dr. Noreen Clark for her thoughtful review of the article and analysis.
Footnotes
This work was funded by the Michigan Department of Community Health and by an unrestricted educational grant from GlaxoSmithKline.
Received for publication April 4, 2005. Accepted for publication September 5, 2005.
References
This article has been cited by other articles:
|
|
 |
|
  F. T. Shaya, D. Dongyi, M. O. Akazawa, C. M. Blanchette, J. Wang, D. W. Mapel, A. Dalal, and S. M. Scharf Burden of Concomitant Asthma and COPD in a Medicaid Population Chest, July 1, 2008; 134(1): 14 - 19. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
