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 DOI: 10.1177/1077558710367735 2010 67: 450 originally published online 4 May 2010Med Care Res Rev

XirasagarAbdoulaye Diedhiou, Janice C. Probst, James W. Hardin, Amy B. Martin and Sudha

Emergency Department Use Among Children With AsthmaRelationship Between Presence of a Reported Medical Home and

  

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Medical Care Research and Review67(4) 450 –475

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DOI: 10.1177/1077558710367735http://mcr.sagepub.com

Relationship Between Presence of a Reported Medical Home and Emergency Department Use Among Children With Asthma

Abdoulaye Diedhiou1, Janice C. Probst1, James W. Hardin1, Amy B. Martin1, and Sudha Xirasagar1

Abstract

This study examined data from the 2005-2006 National Survey of Children with Special Health Care Needs to assess the relationship among children with asthma between a reported medical home and emergency department (ED) use. The authors used 21 questions to measure 6 medical home components: personal doctor/nurse, family-centered, compassionate, culturally effective and comprehensive care, and effective care coordination. Weighted zero-inflated Poisson regression analyses assessed the independent effects of having a medical home on annual number of child ED visits while controlling for child and parental characteristics, and the differential likelihood of securing a medical home. Nearly half (49.9%) of asthmatic children had a medical home. Receiving primary care in a medical home was associated with fewer ED visits (incidence rate ratio = 0.93; 95% confidence interval = 0.89-0.97). A medical home in which physicians and parents share responsibility for ensuring that children have access to needed services may improve child and family outcomes for children with asthma.

This article submitted to Medical Care Research and Review on September 30, 2009, was revised and accepted for publication on February 24, 2010.

1University of South Carolina, Columbia

Corresponding Author:Abdoulaye Diedhiou, South Carolina Public Health Consortium, Arnold School of Public Health, University of South Carolina, 800 Sumter Street, Suite 309, Columbia, SC 29208Email: diedhiou@mailbox.sc.edu

Diedhiou et al. 451

Keywords

primary care, medical home, emergency department, childhood asthma, special health care needs

Asthma is the leading chronic illness in children in the United States (Newacheck & Halfon, 2000). In 2008, 14% of children younger than 18 years of age (nearly 10 million) had ever been diagnosed with asthma, and 10% (7 million) currently had asthma (Bloom, Cohen, & Freeman, 2009). Children in minority and poor families still bear a disproportionate asthma burden (Akinbami, Moorman, Garbe, & Sondik, 2009) and experience higher rates of fatalities and other adverse events such as hospital admis-sions, and emergency department (ED) visits due to asthma (McDaniel, Paxson, & Waldfogel, 2006). Those potentially preventable outcomes along with the excessive use of rescue medications comprise the majority of exacerbation-related treatment costs and account for a large proportion of the economic burden of asthma (Wang, Villar, Mulligan, & Hansen, 2005; Weiss & Sullivan, 2001). Other substantial social and economic consequences of pediatric asthma include absence from school and lost workdays for families and caregivers, poor quality of life, and behavioral disorders (Weiss & Sullivan, 2001).

As an integrative method of health service delivery, the medical home has been advocated by the American Academy of Pediatrics (AAP), the National Association of Pediatric Nurse Practitioners (NAPNP), and the Federal Maternal and Child Health Bureau (MCHB) to reduce barriers to effective care for children with chronic condi-tions, including children with asthma (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004; MCHB, 2008; NAPNP, 2007). A practice may be described as offering a “medical home” if the care it provides can be characterized as “accessible, continuous, comprehensive, family-centered, coordi-nated, compassionate, and culturally effective” (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004). By fostering part-nerships between parents and physicians, a medical home offers a unique opportunity to improve management of children with chronic conditions. Family-centered child-hood asthma care ensures, among other outcomes, that prescriptions are filled, medi-cations are taken on time, environmental controls are implemented, and necessary check-up visits are attended. Therefore, a national maternal and child health agenda includes the provision of a medical home to each child with chronic condition by 2010 (MCHB, 2008).

However, nearly two decades after the concept was first introduced in the 1990s, published studies documenting the presence and correlates of a medical home and/or the resultant benefits are limited and have faced the challenge of measuring the con-cept using available survey or administrative data. In addition, generalizing findings remains problematic since most studies examined nonrepresentative samples and defined the medical home concept in differing ways (Starfield & Shi, 2004). Studies of the association between care provided in the medical home model and outcomes among children with asthma are similarly limited in number, scope, and design. To

452 Medical Care Research and Review 67(4)

date, no prospective longitudinal studies have been reported. The few retrospective and cross-sectional studies specifically addressing childhood asthma have yielded mixed results because of relatively small samples (Kempe et al., 2000), measurement limitations related to survey data used (Kieckhefer, Greek, Joesch, Kim, & Baydar, 2005), or lack of examination of health service utilization benefits (Brachlow, Ness, McPheeters, & Gurney, 2007; Stevens, Pickering, Seid, & Tsai, 2009).

The single nationally representative study of the relationship between care pro-vided in the medical home model and ED visits in childhood asthma did not find effects (Kieckhefer et al., 2005). However, the data set used by Kieckhefer and col-leagues, the Medical Expenditure Panel Survey (MEPS), has been criticized for failing to capture key dimensions of the medical home concept, including components such as “continuous,” “compassionate,” “family-centered,” and “culturally effective” care (Bethell, Read, & Brockwood, 2004). Thus, the relationship between receipt of care within the medical home model and adverse outcomes among children with asthma, such as ED use, remains unexplored. The purpose of the present study was to assess the relationship between receipt of care from a provider offering services consistent with a “medical home” and ED visits among children with asthma.

New ContributionOur research used nationally representative data for children with special health care needs from the 2005-2006 National Survey of Children with Special Health Care Needs (NS-CSHCN). Compared with the MEPS, The NS-CSHCN provides better measurement of the medical home, as it was designed to collect extensive data regard-ing characteristics of a medical home for infants, children, and adolescents with special health care needs (Bethell et al., 2004). In addition, our analytical approach used propensity scores (Rosenbaum & Rubin, 1983) to address another major short-coming of previous observational studies, bias in the nature of children receiving care at a practice using the medical home model. The propensity score method involves calculating the conditional probability, that is, propensity, of being in the treated group (e.g., receiving care consistent with the medical home model) given a set of covariates, sampling the data based on these propensity scores, and then analyzing the outcome using the sampled data (Rosenbaum & Rubin, 1983).

Research has consistently documented that race/ethnicity, health insurance, income, language spoken, education, and condition severity and functional limitation are sig-nificant predictors of access to care provided in the medical home model among chil-dren with chronic conditions (Brachlow et al., 2007; Fulda, Lykens, Bae, & Singh, 2009; Stevens et al., 2009; Strickland et al., 2009). The unequal distribution of these child and parental characteristics that affect the likelihood to secure care consistent with the medical home model must be accounted for in any attempt to examine the benefits of a medical home for the pediatric population with special health care needs. Our study reduced selection bias by matching children with and without care consistent with the medical home concept using the propensity score approach.

Diedhiou et al. 453

Conceptual Model

We used Andersen’s (1995) behavioral model of health services utilization as a frame-work for examining the expected relationship between access to care consistent with the medical home concept and health services utilization. According to Andersen, an individual’s pattern of health service use is a function of predisposing characteristics, enabling resources, and more directly the need for care. These factors are themselves influenced by the available system of care, including the organization of care, policies and community resources. Multiple feedback loops characterize the relationships among constructs in Andersen’s model. Initial use of health services, for example, can generate the need for subsequent health care services.

According to Andersen’s (1995) model, predisposing characteristics reflect the individual-level factors that influence the use of health services. In the present study, predisposing factors included the child’s age, gender, and race/ethnicity. Gender- and age-based differences in health services utilization have been documented. A study of asthma patients by Schatz and Camargo (2003) reported greater health services utili-zation in males aged 2 to 13 years, somewhat greater in females aged 14 to 22 years, and definitely greater in females aged 23 to 64 years. Similarly, research studies show that in addition to being disproportionately affected by the disease (Akinbami et al., 2009), racial/ethnic minority children have greater lifetime stories of ED admissions and hospitalizations for asthma complications (McDaniel et al., 2006).

Enabling resources refer to the potential to access health services, that is, the vari-ables that facilitate the use of desired health care services (Andersen, 1995). Enablers in the present study included insurance (type and continuity of coverage), socioeco-nomic variables (education, income), place of residence, geographic region, and lan-guage ability. Uninsurance has been associated with inadequate use of health services, including ED and inpatient services (Lieu et al., 2002). Research has also established that having adequate health insurance is a key contributor to access to and continuity of asthma care services. For instance, Bratton et al. (2006) recently reported that Medicaid-insured children with asthma are less likely to receive health care services within the recommended national guidelines.

Financial resources play an important role in an individual’s ability to access and use health services. In 2008, nearly 2 million children in the United States were unable to get needed medical care because their families could not afford it, and medical care for 3.5 million children was delayed because of worries about cost (Bloom et al., 2009). Studies examining the link between socioeconomic status and asthma confirm that children in poor or near-poor families are more likely to have unmet medical needs and delayed medical care, and to rely on EDs as their usual source of care than those in higher income families (MCHB, 2008).

Access to care and utilization are major issues in rural and inner-city areas, which experience poorer health care resources. Patients with higher spatial accessibility to primary care services have been found to make significantly more scheduled visits for asthma care, and subsequently fewer urgent care visits (Teach et al., 2006). Inner-city

454 Medical Care Research and Review 67(4)

and rural children with asthma depend heavily on hospital EDs as their usual source of asthma care (U.S. Department of Health and Human Services, 2002).

Research has documented the role of language ability in accessing and using health services. Yu, Nyman, Kogan, Huang, and Schwalberg (2004) reported that children with special health care needs from non-English-speaking families were more likely to face barriers in accessing health care services than children from English-speaking families. Additional enablers (or barriers) of health care utilization include family structure, and presence of siblings, particularly siblings with special health care needs. Data from the 2008 National Health Interview Survey suggest that children in single-mother families are more likely to lack or delay medical care compared with children in two-parent or single-father families. In addition, they are more likely to have made two or more trips to an ED in the past 12 months than children in two-parent families (Bloom et al., 2009).

Need factors reflect the presence and severity of conditions for which health care services are sought (Andersen, 1995). Acute exacerbations are the leading cause of ED visits in childhood asthma. Comorbidities such as behavioral–emotional–developmental disorders and parents’ perception of the severity of health difficulties caused by their child’s asthma as well as their perception of the burden the condition puts on the family, influence the use of health care services in childhood asthma, resulting in a higher like-lihood of being hospitalized or using emergency services (Valerio et al., 2006).

In Andersen’s model, the organization of the system of care represents the broadest level of influence on health service utilization (Andersen, 1995) and is the subject of the present study. Asthma is an ambulatory care–sensitive condition, that is, a condi-tion for which costly ED visits and hospitalizations can be avoided or delayed if appropriately managed in ambulatory settings. An important body of research has established the role of access to comprehensive and quality primary care in reducing ED utilization and hospital admissions in the pediatric population (Smith, Wakefield, & Cloutier, 2007; Wang et al., 2005). Care organized according to the principles of a primary care medical home is expected to reduce barriers to and ensure adequate use of quality health care services for children with chronic conditions, including children with asthma (AAP & Medical Home Initiatives for Children With Special Needs Proj-ect Advisory Committee, 2004; Cooley & McAllister, 2004, NAPNP, 2007).

Historically, the presence of a medical home has been determined by the reporting of a usual source of care and or personal doctor/nurse. However, the definition of a pediatric medical home has evolved to specify “accessible, continuous, comprehensive, family-centered, coordinated, compassionate, and culturally effective” health care. These 7 attributes covering 37 specific topics are fully described elsewhere (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004). The medical home concept implies shared responsibility between doctors and parents in ensuring that children have access to all medical and nonmedical services needed to achieve their maximum potential (Cooley & McAllister, 2004). Although, the AAP has recommended that all children have a medical home, it has also acknowl-edged that children with chronic conditions or special health care needs might most

Diedhiou et al. 455

readily realize the proposed benefits (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004). In the research reported here, we examine whether receipt of care consistent with the medical home concept is asso-ciated with lower ED visits rates among children with asthma, holding constant their predisposing, enabling, and need characteristics. The relationship of variables mea-sured to constructs from the Andersen model is shown in Table 1.

Table 1. Study Variables, Measurement Levels, and Link With the Theoretical Framework

Constructs of Andersen’s Model and Study Variables Measurement Levels

Health care system Medical home Yes, no

Individual characteristics Predisposing

Race/ethnicity Hispanic, non-Hispanic White, non-Hispanic Black, Multiple race/ethnicity, other race/ethnicitya

Age group (years) 0-5, 6-11, 12-17Gender Female, male

Enabling Primary language spoken English, other languageLanguage of interview English, other languageParental income, as % FPLb 0%-200%, 201%-400%, >400%Parental educational attainment Less than high school, high school/GED, more than high schoolType of health insurance Uninsured, public, privateContinuity of insurance coverage Gaps in coverage, insured full yearFamily structure Two biological/adoptive parents, two step-parents, single mother, other structurePresence of siblings Yes, noSiblings with special health care needs Yes, noResidence/location, per MSA statusc MSA, non-MSA, missingGeographic region Northeast, South, Midwest, West

Need Perceived asthma severity No/minor, moderate, severeComorbiditiesd Yes, no

Health service utilization ED visits Number in past 12 months

Note: FPL = federal poverty level; MSA = Metropolitan Statistical Area; ED = emergency department.a. Other race/ethnicity includes respondents identified as non-Hispanic and Asian, Alaska Native, American Indian, Native Hawaiian, or Pacific Islander.b. FPLs are based on the U.S. Department of Health and Human Services poverty guidelines, adjusted for survey year (2005, 2006).c. An MSA consists of a county or group of counties containing at least one urbanized area of 50,000 or more population, and other adjacent counties that are economically and socially integrated with the central city.d. Comorbidities included behavioral, emotional and developmental disorders (“attention deficit disorders,” “autism spectrum disorders,” “Down syndrome,” “mental retardation,” and “emotional problems”), diabetes, blood or heart problems, food allergies, and muscular dystrophy and other rare conditions.

456 Medical Care Research and Review 67(4)

MethodStudy Population and Data SourceThe 2005-2006 NS-CSHCN is a nationally representative telephone survey of the noninstitutionalized civilian population sponsored by the Federal Maternal and Child Health Bureau (MCHB) and conducted by the National Center for Health Statistics. The survey was designed to obtain detailed information on health status, health care experiences, and family impacts of children aged 0 to 17 years with special health care needs (CSHCN) in the United States. The response rate was 61.2% with 40,723 interviews completed in 2005-2006. Further information regarding the design and operation of the NS-CSHCN is presented elsewhere (Blumberg et al., 2008). Inter-views were conducted with the parent or legal guardian who was most knowledgeable about the child’s health and health care; overall, 78% of respondents were mothers (Blumberg et al., 2008). The sample for the present study was restricted to CSHCN reported to have asthma at the time of the interview (n = 14,916). Children were identified as having asthma when the household informant responded “Yes” to the question: “To the best of your knowledge, does [sample child] currently have any of the following: Asthma?”

Dependent Variable: ED VisitsThe number of reported ED visits by the child within the past 12 months was our outcome measure of health service utilization. ED visits are among indicators of individual and health system performance regarding the management of pediatric asthma (Fuhlbrigge et al., 2004). As potentially preventable outcomes, ED admissions among children with asthma are a good measure of access to and use of quality ambulatory primary care (Mattke, Martorell, Sharma, Malveaux, & Lurie, 2009).

Independent Variable: Reported Medical HomeOur independent variable was a reported medical home, a dichotomous measure of the nature of care received. The measure incorporates five of the seven domains specified by the AAP as defining a medical home that could be assessed using data from the NS-CSHCN. We used “medical home” to indicate the receipt of care that included the five available dimensions of the AAP medical home concept, including comprehensive care with no problems obtaining referrals; effective care coordina-tion; family-centered, compassionate, and culturally effective care. In assessing whether a child received care consistent with the medical home concept or not, we used on every rating approach rather than across all approach. Both rating criteria were proposed by Bethell et al. (2004) based on components of the medical home described by the AAP and Medical Home Initiatives for Children With Special Needs Project Advisory Committee (2004). In short, the “on every” approach requires that a child experiences good care in each domain of the medical home to

Diedhiou et al. 457

qualify as receiving care consistent with that of a medical home, while the alternative considers whether the child experiences, on average, good care across all domains of a medical home (Bethell et al., 2004).

We chose the “on every” approach to be conservative in defining receipt of care in the medical home model. Specifically, a child was categorized as having a medical home if the respondent (a) reported that he or she had a personal doctor or nurse who is also their usual source for sick and well care and (b) satisfied each of the five com-ponents listed above. However, only Criterion 1 was mandatory, as the five compo-nents did not apply universally to all children in the sample. A child would qualify as a legitimate skip when he or she did not need the service(s) being assessed under a component of medical home. The rating algorithm is presented in Table 2. A listing of survey items used is provided in the appendix.

Control VariablesPredisposing covariates included the child’s age, gender, and race/ethnicity. Age was categorized into three groups: 0 to 5 years, 6 to 11 years, and 12 to 17 years. We con-structed race/ethnicity from self-reported race and Hispanic origin, and categorized as following: Hispanic, non-Hispanic White, non-Hispanic Black, multiple race, and other race/ethnicity for respondents self-identified as Asian, Alaska Native, American Indian, Native Hawaiian, or Pacific Islander.

Enabling variables included primary language spoken in the household (English or other language), language of interview (English or other language), family struc-ture (categorized into: single mother family, two-parents biological/adoptive fam-ily, two-parents step-family, and other family structure), presence of siblings, presence of siblings with special health care needs (SHCN), household income (measured as percentage of the federal poverty level [FPL] and categorized as fol-lowing: 0% to 200% FPL; 201% to 400% FPL, and >400% FPL), highest educa-tional attainment in the household (categorized as follows: less than high school, high school graduate or General Educational Development (GED) completed, and more than high school), type of health insurance (based on reported type of insur-ance and entailed the following categories: privately insured, publicly insured, and uninsured), consistency of insurance coverage over the past year, place of resi-dence (based on Metropolitan Statistical Area [MSA] status and identified as non-MSA, MSA, and missing), and major U.S. Census region (derived from the child’s state of residence and grouped into the four major regions: Northeast, South, Mid-west, and West).

The determination of FPLs was based on the U.S. Department of Health and Human Services poverty guidelines adjusted for survey year (2005, 2006). An MSA consisted of a county or group of counties containing at least one urbanized area of 50,000 or more population, and other adjacent counties that are economically and socially inte-grated with the central city. Missing, “don’t know,” or “refused” responses to ques-tions were excluded from the analyses, with the exception of MSA status. Because

458 Medical Care Research and Review 67(4)

Table 2. Algorithm for Measuring the Medical Home

Componenta Description Observations

The child had . . .A personal doctor/nurse One or more health care providers

are considered to be personal doctor/nurse and usual sources for sick and well care in the past 12 months

Mandatory criterion, no legitimate skip

AND the child received . . .Family-centered, culturally effective, compassionate care

Seven items used and assigned a value of “Yes” if parents responded “Usually” or “Always” to all relevant questions

Legitimate skip if no visit to a doctor/nurse during the past 12 months

Comprehensive careNo problems obtaining referrals

Two items used and assigned a value of “Yes” if respondents indicated the child needed to obtain a referral in order to see other doctors or receive services and responded “Not A Problem” getting the needed referrals

Legitimate skip if referrals not needed

Usual source(s) for both sick and well care

Five items used and assigned a value of “Yes” if respondents indicated the child had regular source(s) other than the hospital emergency room for both sick and well care

Mandatory criterion, no legitimate skip

Effective care coordinationHelp coordinating child’s care

Three items and assigned a value of “Yes” if respondents indicated someone helped the family with coordinating the child’s care and/or the family was “Always” able to get extra help when needed during the past 12 months and/or, if needed, the child used any of five specialized services

Legitimate skip if no help needed coordinating care

Communication between providers

Three items and assigned a value of “Yes” if respondents indicated they were “Very Satisfied” with communication between child’s doctors and/or, if needed, they were “Very Satisfied” with communication between child’s doctors and school or other community programs

Legitimate skip if no communication needed

a. Components of the American Academy of Pediatrics definition of the medical home not covered in the National Survey of Children with Special Health Care Needs include “Accessible” and “Continuous” care.

Diedhiou et al. 459

10% of observations for MSA status were missing, a “missing” category was created to prevent loss of these observations.

Need covariates included respondent-perceived severity of the child’s condition (categorized as minor, moderate, and severe), and the presence of comorbidities such as behavioral–emotional–developmental [BED] disorders, diabetes, blood and heart prob-lems, food allergies, and muscular dystrophy and other rare conditions. BED disorders included “attention deficit disorders,” “autism spectrum disorders,” “Down syndrome,” “mental retardation,” and “emotional problems.”

AnalysisAnalyses were conducted using STATA software (version 10, StataCorp, College Sta-tion, TX; see StataCorp LP, 2008). All analyses accounted for the complex multistage sampling design of the survey using sampling weights for probability, strata, and primary sampling units provided (Blumberg et al., 2008). In bivariate analyses, we used the chi-square test to compare proportions of children with and without a medi-cal home, and the t test to compare mean ED visits between children with and without a medical home. Since our outcome variable (number of ED visits per 12 months) is a nonnegative count with probability of zero exceeding the usual Poisson distribu-tion, we used zero-inflated Poisson (ZIP) regression analysis to assess the independent effects of a reported medical home on ED visits while controlling for child and paren-tal characteristics.

In preliminary analyses, we found that children with asthma whose families reported a medical home differed from other children in a systematic way. To account for children’s unequal probability of securing a medical home in multi-variate analyses, we first used logistic regression to compute the child’s likeli-hood of having a medical home (hereafter, propensity score). Second, we ranked all observations based on propensity score and stratified observations into five groups, defined by the quintiles of the propensity scores. Then we performed the ZIP regression analysis using a technique known as random selection within strata (Rosenbaum & Rubin, 1983). In this approach, equal numbers of observa-tions in the treatment (medical home) and control (no medical home) groups are randomly selected for analysis (as matched pairs) within each of the groups defined by the propensity score quintiles. Given nonmatched observations are excluded from regression analyses, the final number of observations for the mul-tivariate analysis was 11,831.

We calculated incidence rate ratios (IRR) and their 95% confidence intervals (95% CI) from estimated regression coefficients. Since all of the covariates included in the model were categorical variables, each IRR represents the incidence rate ratio of a particular category to the reference category for the associated covariate. Statistical significance was assessed at a = .05 level of significance.

460 Medical Care Research and Review 67(4)

ResultsCharacteristics of the Study PopulationCharacteristics of children with asthma (n = 14,916) reached by the 2005-2006 NS-CSHCN are shown in Table 3. Nearly 80% of children were aged between 6 and 17 years, two thirds were male, and 59% were non-Hispanic White children. Children with asthma in the present study were overwhelmingly from English-speaking families (95.4%). More than half (54.1%) lived with their two parents while nearly a third (32.3%) lived with a single mother. Almost 36.5% had siblings who also had special health care needs. About 70% of children were from highly educated families, and 55.4% from families that earned income above 200% of the FPL. Overall, 58% of children were privately insured, 3.4% were uninsured at the time of interview, and only 9% lacked consistent coverage during the past calendar year; however, children aged 12 to 17 years represented 40.2% of those who had gaps in insurance coverage, while children aged 0 to 5 years represented 23.7%. Three quarters of children (75.1%) lived in urban areas, and nearly 4 in 10 in southern states of the United States. Respondents rated the severity of their child’s health condition as minor in 63.5% of cases. More than a quarter (27.8%) of chil-dren had one or more comorbid BED disorders, while nearly 16% reported food allergies.

Approximately half of children (49.9%) received care consistent with that of a medical home. Children receiving care consistent with a medical home differed sys-tematically from those who did not (Table 3). Among predisposing characteristics, 67.6% of children who received medical home care were Non-Hispanic White, while minority and mixed race/ethnicity children were disproportionately represented in the opposite group. Multiple enabling characteristics were associated with receipt of med-ical home care. A two-parent family structure, the presence of siblings, English lan-guage facility, higher income and higher education were all were associated with receipt of medical home care (Table 3). Presence of siblings who had special health care needs was not associated with reporting medical home care. Of note, children with private health insurance and no insurance gaps were more likely to be receiving medical home care. Among need factors, asthma severity was inversely related to the likelihood of receipt of medical home care. Comorbid BED disorders, blood or heart problems, and muscular dystrophy or other conditions were negatively associated with medical home status.

Bivariate RelationshipsChildren with asthma experienced on average 1.2 ED visits in a year. However, nearly 56% had no ED visits in the past calendar year, 30% reported 1 or 2 visits, and 14% had 3 or more visits. Children with asthma who received medical home

Diedhiou et al. 461

Table 3. Characteristics of Children with Asthma (n = 14,916), Total and by Receipt of Care Consistent With a Medical Home, 2005-2006 NS-CSHCN

Weighted Percentagesa (Standard Errors)

Care Consistent With Medical Home Model All Children With Covariate Asthma (100.0%) Yes (49.85%) No (50.15%) Pb

Predisposing characteristics Age (years) .705

0-5 22.43 (0.59) 22.85 (0.82) 22.15 (0.82) 6-11 39.76 (0.69) 39.89 (0.99) 39.53 (1.00) 12-17 37.82 (0.67) 37.26 (0.92) 38.32 (1.00)

Gender .735Female 39.83 (0.68) 40.13 (0.95) 39.66 (1.01)

Race/ethnicity <.001Non-Hispanic White 58.61 (0.71) 67.57 (0.97) 50.37 (1.03) Non-Hispanic Black 21.88 (0.62) 17.23 (0.80) 26.52 (0.96) Hispanic, any race 12.50 (0.51) 8.61 (0.64) 15.94 (0.81) Multiple race/ethnicity 4.14 (0.27) 4.07 (0.42) 4.19 (0.36) Other race/ethnicityc 2.86 (0.24) 2.51 (0.29) 2.98 (0.35)

Enabling factors Primary language spoken <.001

English 95.37 (0.35) 97.87 (0.36) 93.32 (0.58) Language of interview <.001

English 96.38 (0.32) 98.33 (0.33) 94.90 (0.53) Family structure <.001

Two biological/ 54.10 (0.71) 60.84 (0.99) 47.53 (1.05) adoptive parents Two step-parents 9.58 (0.43) 8.83 (0.55) 10.31 (0.68) Single mother 32.25 (0.68) 27.15 (0.93) 37.44 (1.03) Other structure 4.07 (0.26) 3.18 (0.29) 4.72 (0.45)

Child has siblings .001Yes 72.49 (0.57) 74.40 (0.76) 70.54 (0.88)

Child has siblings with SHCN .125Yes 36.46 (0.73) 37.54 (1.03) 35.27 (1.07)

Family income, % FPLd <.001>400 26.67 (0.61) 32.24 (0.91) 21.80 (0.84) 201-400 28.75 (0.60) 32.45 (0.89) 25.40 (0.84) 0-200 44.58 (0.70) 35.31 (0.97) 52.80 (1.02)

Highest education <.001More than high school 68.91 (0.69) 74.26 (0.93) 64.41 (1.03) High school graduate/GED 23.79 (0.63) 21.00 (0.87) 26.32 (0.95) Less than high school 7.30 (0.42) 4.74 (0.48) 9.27 (0.68)

Insurance type <.001Private 57.84 (0.70) 66.83 (0.95) 49.73 (1.03)

(continued)

462 Medical Care Research and Review 67(4)

Table 3. (continued)

Weighted Percentagesa (Standard Errors)

Care Consistent With Medical Home Model All Children With Covariate Asthma (100.0%) Yes (49.85%) No (50.15%) Pb

Public 38.80 (0.70) 31.14 (0.94) 45.72 (1.03) Uninsured 3.35 (0.26) 2.03 (0.28) 4.55 (0.44)

Insurance coverage, past 12 months <.001

Gaps in coverage 9.03 (0.42) 5.62 (0.44) 11.81 (0.68) Location, MSA statusf .691

MSA 75.08 (0.49) 74.77 (0.72) 75.56 (0.73) Non-MSA 14.90 (0.44) 14.92 (0.64) 14.53 (0.63) Missing 10.02 (0.23) 10.31 (0.36) 9.91 (0.36)

Geographic region .001Northeast 18.30 (0.44) 19.18 (0.70) 17.62 (0.67) South 38.83 (0.59) 37.28 (0.88) 40.38 (0.94) Midwest 22.91 (0.46) 24.89 (0.72) 21.16 (0.71) West 19.96 (0.58) 18.65 (0.87) 20.84 (0.91)

Need factors Perceived asthma severity <.001

No/minor 63.48 (0.68) 72.58 (0.89) 54.85 (1.02) Moderate 30.17 (0.64) 24.22 (0.85) 35.74 (0.97) Severe 6.35 (0.36) 3.19 (0.38) 9.41 (0.64)

BEDe disorders <.001Yes 27.84 (0.64) 19.43 (0.77) 36.23 (1.02)

Diabetes .057Yes 0.70 (0.11) 0.50 (0.10) 0.94 (0.21)

Blood or heart problems .028Yes 5.41 (0.36) 4.52 (0.46) 6.08 (0.54)

Food allergies .334Yes 15.99 (0.50) 15.56 (0.69) 16.55 (0.75)

Muscular dystrophy and other .001Yes 3.43 (0.27) 2.43 (0.34) 4.31 (0.44)

Note: NS-CSHCN = National Survey of Children with Special Health Care Needs; FPL = federal poverty level; MSA = Metropolitan Statistical Area; BED disorders = behavioral, emotional, and developmental disorders.a. The figures represent the national population of children with special health care needs.b. Chi-square test of the difference in proportions of children with and without a medical home.c. Other race/ethnicity includes respondents identified as non-Hispanic and Asian, Alaska Native, American Indian, Native Hawaiian, or Pacific Islander.d. FPLs are based on the U.S. Department of Health and Human Services poverty guidelines, adjusted for survey year (2005, 2006).e. Behavioral, emotional, and developmental disorders, include “attention deficit disorders,” “autism spectrum disorders,” “Down syndrome,” “mental retardation,” and “emotional problems.”f. Urban or rural place of residence. An MSA consists of a county or group of counties containing at least one urbanized area of 50,000 or more population, and other adjacent counties that are economically and socially integrated with the central city.

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care had significantly fewer ED visits than their peers without such care (0.9 vs. 1.4 visits per year; Table 4). However, as noted in Table 3, children with a reported medical home were less likely to have parentally assessed moderate or severe asthma. These distributions mirrored a dose–response pattern between the severity of the child’s condition, the likelihood of securing a medical home, and the number of ED visits: as the severity of the child’s condition increased, the likelihood of meeting all the criteria for a medical home decreased (Table 3), and the number of ED visits increased (Table 4).

Beside perceived disease severity, the unadjusted risk profile for increased ED vis-its included several other factors. Predisposing characteristics associated with higher ED visit rates were race/ethnicity (Black, Hispanic, or multiple race/ethnicity), and age (younger than 6 years). Enabling factors for increased ED visits included being uninsured, publicly insured, or inconsistently insured; living in the U.S. South; living with step-parents or a single mother who did not graduate in high school; and earning income at or below 200% of the FPL. Increasing asthma severity and all comorbidities were associated with higher ED visit rates.

Multivariable (Adjusted) RelationshipsThe adjusted association between receipt of care that presented the attributes of a medical home and ED visits is presented in Table 4. To reduce bias associated with differing likelihood of receiving care consistent with a medical home, this analysis was conducted using the propensity score method described previously. Children with asthma whose family obtained care from a source meeting the definition of a medical home had 7% fewer ED visits than their peers who did not have a medical home (IRR = 0.93; 95% CI = 0.89-0.97). Factors that remained significantly associated with lower risk of ED visits included being a child aged 6 years or older and reporting con-sistent insurance coverage in the past 12 months, an enabling factor.

However, after adjusting for child and parental characteristics, and access to a medical home, the profile of risk for increased child ED visits changed in several ways from that noted in bivariate analysis. Among predisposing characteristics, gender became significant, with male children having a reduced visit rate. Con-versely, Hispanic and White children ceased to differ. Enabling factors such as uninsurance, less than high school parental education, having siblings with special health care needs, and living in the South were no longer risk factors. Likewise, having one or more BED disorders was no longer associated with increased ED visits among children with asthma. Other changes in the risk profile involved an increased risk of ED visits among children from non-English-speaking families, and children in families earning income up to 400% of FPL. Likewise a twofold increase in ED visits was observed among children whose condition was rated as severe, a key need factor.

464 Medical Care Research and Review 67(4)

Table 4. Means (and Standard Errors) and Incidence Rate Ratios (and 95% CI) of ED Visits Among Children With Asthma, 2005-2006 NS-CSHCN

Bivariate Associations Multivariable Associations (n = 14,916) (n = 11,831a)

Parameter Mean (SE) Pb IRRc (95% CI) Pd

System of care Medical home reported <.001

No 1.44 (0.05) 1.00 (reference) Yes 0.90 (0.04) 0.93 (0.89-0.97) <.001

Predisposing characteristics Age (years) <.001

0-5 1.79 (0.08) 1.00 (reference) 6-11 0.99 (0.04) 0.74 (0.71-0.79) <.00112-17 1.02 (0.05) 0.77 (0.73-0.81) <.001

Gender .962 Female 1.18 (0.05) 1.00 (reference) Male 1.18 (0.04) 0.93 (0.90-0.97) .001

Race/ethnicity <.001 Non-Hispanic White 0.96 (0.03) 1.00 (reference) Non-Hispanic Black 1.72 (0.09) 1.14 (1.08-1.21) <.001Hispanic, any race 1.23 (0.08) 1.00 (0.93-1.08) .979Multiple race/ethnicity 1.40 (0.12) 1.15 (1.05-1.26) .002Other race/ethnicitye 0.93 (0.11) 1.01 (0.91-1.12) .827

Enabling factors Primary language spoken .819

English 1.18 (0.03) 1.00 (reference) Other language 1.15 (0.12) 1.32 (1.14-1.52) <.001

Language of interview .914 English 1.18 (0.03) 1.00 (reference) Other language 1.16 (0.13) 0.72 (0.60-0.87) .001

Family structure <.001 Two biological/adoptive parents 0.88 (0.03) 1.00 (reference) Two step-parents 1.50 (0.15) 1.15 (1.08-1.24) <.001Single mother 1.59 (0.06) 1.08 (1.02-1.13) .004Other structure 0.98 (0.12) 1.04 (0.93-1.16) .533

Child has siblings .083 No 1.26 (0.05) 1.00 (reference) Yes 1.15 (0.04) 0.99 (0.95-1.04) .768

Child has siblings with SHCN .048 No 1.13 (0.03) 1.00 (reference) Yes 1.27 (0.06) 1.04 (0.99-1.09) .128

Family income, % FPLf <.001 >400 0.61 (0.03) 1.00 (reference) 201-400 0.91 (0.05) 1.14 (1.06-1.23) .0010-200 1.70 (0.05) 1.35 (1.25-1.46) <.001

Highest education <.001 More than high school 0.94 (0.03) 1.00 (reference) High school graduate/GED 1.66 (0.08) 1.12 (1.06-1.17) <.001Less than high school 1.85 (0.15) 0.92 (0.85-1.00) .062

Insurance type <.001 Private 0.74 (0.03) 1.00 (reference) Public 1.81 (0.06) 1.25 (1.18-1.32) <.001

(continued)

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Table 4. (continued)

Bivariate Associations Multivariable Associations (n = 14,916) (n = 11,831a)

Parameter Mean (SE) Pb IRRc (95% CI) Pd

Uninsured 1.40 (0.18) 1.10 (0.96-1.27) .175Insurance coverage, past 12 months <.001

Gaps in coverage 1.62 (0.12) 1.00 (reference) Insured full year 1.13 (0.03) 0.90 (0.83-0.97) .007

Location, MSA statush <.001 MSA 1.11 (0.04) 1.00 (reference) Non-MSA 1.64 (0.09) 1.25 (1.19-1.33) <.001Missing 1.04 (0.05) 0.99 (0.94-1.05) .705

Geographic region <.001 Northeast 1.16 (0.07) 1.00 (reference) South 1.35 (0.05) 0.96 (0.90-1.03) .251

Midwest 1.12 (0.05) 0.93 (0.86-0.99) .045West 0.94 (0.07) 0.94 (0.88-1.01) .084

Need factors Perceived asthma severity <.001

No/minor 0.80 (0.03) 1.00 (reference) Moderate 1.66 (0.06) 1.47 (1.41-1.57) <.001Severe 2.74 (0.19) 2.03 (1.89-2.17) <.001

BEDg disorders <.001 No 1.02 (0.03) 1.00 (reference) Yes 1.57 (0.06) 1.01 (0.96-1.06) .658

Diabetes .003 No 1.17 (0.03) 1.00 (reference) Yes 2.14 (0.32) 1.26 (1.09-1.47) .002

Blood or heart problems <.001 No 1.09 (0.03) 1.00 (reference) Yes 2.55 (0.24) 1.45 (1.35-1.54) <.001

Food allergies .007 No 1.14 (0.03) 1.00 (reference) Yes 1.35 (0.07) 1.13 (1.08-1.19) <.001

Muscular dystrophy and other <.001 No 1.12 (0.03) 1.00 (reference) Yes 2.59 (0.23) 1.21 (1.12-1.31) <.001

Note: 95% CI = 95% confidence interval; ED = emergency department; NS-CSHCN = National Survey of Children with Special Health Care Needs; IRR = incidence rate ratio; FPL = federal poverty level; MSA = Metropolitan Statistical Area; BED disorders = behavioral, emotional, and developmental disorders. Overall 56% of children had no ED visits, 30% reported one or two visits, and 14% had three or more visits.a. In all, 20.7% of the initial 14,916 observations were lost due to exclusion of nonmatches.b. P-value of the t test of difference in means among categories of a covariate.c. Incidence rate ratio or IRR represents the ratio of the number of ED visits in a year among exposed (to a particular covariate) to that of unexposed children.d. P-value associated with the ratio of the rates of ED visits between exposed and nonexposed children.e. Other race/ethnicity includes respondents identified as non-Hispanic and Asian, Alaska Native, American Indian, Native Hawaiian, or Pacific Islander.f. FPLs are based on the U.S. Department of Health and Human Services poverty guidelines, adjusted for survey year (2005, 2006).g. Behavioral, emotional, and developmental disorders include “attention deficit disorders,” “autism spectrum disorders,” “Down syndrome,” “mental retardation,” and “emotional problems.”h. Urban or rural place of residence. An MSA consists of a county or group of counties containing at least one urbanized area of 50,000 or more population, and other adjacent counties that are economically and socially integrated with the central city.

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DiscussionAccess to a Medical HomeConsistent with previous research for the general population of CSHCN (Strickland et al., 2009), our study found that nearly half of children with asthma received care that met the characteristics of a medical home. Correlates of receipt of care that met the definition of a medical home for children with asthma included a number of key predisposing, enabling, and need covariates. Recent studies reached similar conclu-sions for the general population of CSHCN (Brachlow et al., 2007; Fulda et al., 2009; Strickland et al., 2009; Tippy, Meyer, Aronson, & Wall, 2005), and for children with asthma (Stevens et al., 2009). Similarly, there is ample evidence that predisposing characteristics such as Black race, and enabling factors, including poverty, uninsur-ance, and discontinuity of insurance coverage are associated with reduced access to and utilization of health care services in the pediatric population (Grant, Lyttle, & Weiss, 2000; Lieu et al., 2002).

Furthermore, studies examining the link between important enablers such as the socioeconomic status and asthma care confirm that children in poor or near-poor fami-lies are more likely to have unmet medical needs and delayed medical care, and to rely on EDs as their usual source of care than those in higher income families (MCHB, 2008). It is suggested that minority and poor children experience more barriers that may prevent them from adequately using health services, including structural barriers, for example, ability to access the health care system (Seid, 2008), process-of-care bar-riers, for example, ability to navigate the health care system (Martin et al., 2007), and other barriers at the interpersonal level, such as the ability of parents to communicate and work with health care providers to effectively manage the condition (Diette & Rand, 2007). However, contrasting with Fulda and Lykens (2008), we found no asso-ciation between age and receipt of care consistent with a medical home.

While Tippy et al. (2005) reported that insurance was not a predictor of receipt of care in a medical home among Maine-resident children, we found that uninsured, publicly insured, and inconsistently insured children with asthma were least likely to receive care consistent with that of a medical home. Circumstances in which chil-dren lose coverage include changes in insurance eligibility and transition issues, particularly transition to adulthood (AAP, Committee on Adolescence and Commit-tee on Child Health Financing, 2009). The positive association between health insurance coverage and securing a medical home is of particular importance for policy. First, uninsurance or underinsurance are modifiable factors that can be addressed through efforts to expand and maximize insurance coverage. Second, one of the central premises of the medical home concept is to promote access to quality primary care for all children, particularly CSHCN, regardless of their insurance and socioeconomic status, through partnerships between health care providers, families, payers, and other resources in the community (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004; Cooley & McAllister, 2004). In addition, in an ideal medical home, changes in children’s insurance should

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be “accommodated” (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004).

However, our findings underscore the challenge facing primary care providers in achieving the attributes of the patient-centered medical home for patients with chronic conditions, including children and adults. Although the consequences of not providing adequate health care to chronically ill patients are well known, addressing their needs appropriately has been difficult, in part because of the fragmented care delivery sys-tem. Poor communication between primary care physicians and specialists, for exam-ple, can hinder the effective management of chronic diseases; some components of care may be duplicated while others may be overlooked. In addition, the absence of an appropriate interface between the health system and other resources in the community, including nonmedical services, may hinder the quality of care for patients with chronic conditions because neither side understands the full extent of the patients’ problems. Care fragmentation also frustrates patients and families, who find it difficult to navi-gate among the various providers and often feel that there is no one person who can help them get all essential services.

A recent joint-statement from four physician organizations (American Academy of Family Physicians, the American Academy of Pediatrics, the American College of Physicians, and the American Osteopathic Association) reemphasized the importance of the patient-centered medical home for individuals with chronic conditions, regard-less of age, and propose a set of key practice-based care attributes and actions steps for providing comprehensive primary care for children, youth and adults in a health care setting (Kellerman & Kirk, 2007). However, approaches in building and scaling-up sustainable medical homes are still subject to much debate. Some of the pending dis-cussions include whether incremental changes are a better approach than radical ones, and whether changes should occur first within small independent physician practices (bottom up) or should espouse a top-down approach, starting within larger integrated health care organizations (AcademyHealth, 2009).

We also found an inverse relationship between parent-reported severity of asthma and the likelihood of having a medical home. As respondents’ rating of the severity of the child’s condition increased, the proportion of children who received care consistent with that of a medical home decreased. This disturbing pattern has also been reported by Strickland et al. (2009) and Fulda et al., (2009), and raises serious concerns about the capacity of current fragmented health systems to meet the needs of children with more severe conditions and functional limitations who may need more care coordina-tion (Cooley & McAllister, 2004). When the condition is severe, parents may have the perception that their child is not receiving enough needed services and coordination of care. This pattern may also be explained by endogeneity due to omitted variables.

Benefits of a Medical HomeWe sought to provide clinicians, public health professionals, families and patients, insurers, and policy makers with quantitative evidence of whether or not striving to

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provide a medical home may be an effective strategy for keeping children with asthma out of hospital emergency rooms. Using the framework proposed by Andersen and colleagues, we examined the association between receiving care that met the charac-teristics of a medical home and ED visits. Unlike Kieckhefer et al. (2005), we found that children with asthma whose care reflected the characteristics of a medical home experienced lower rates of ED visits. The relationships persisted even after controlling for both child and parental characteristics and the propensity to have a medical home. Additionally, family link to care that presented the characteristics of a medical home mitigated the negative effect of uninsurance and Hispanic ethnicity on ED visits.

Our findings are consistent with previous research documenting the relationship between the disproportionate use of hospital EDs for asthma care among vulnerable children and poor access to primary care (Smith et al., 2007; Wang et al., 2005). Accessing and coordinating health services represent a constant challenge for families of children with chronic conditions who often face geographic and financial barriers to care (Martin et al., 2007). Furthermore, poor communication and cultural misunder-standings are additional concerns for both families and providers. By fostering shared responsibility between families, health care providers and other community resources, the availability of care consistent with the characteristics of a medical home provides enhanced health care services for those children in their communities (Cooley & McAllister, 2004).

In addition, research has documented that poor management and control of pedi-atric asthma increase exacerbations resulting into ED and inpatient admissions (Sullivan et al., 2007), overuse of rescue medications, indirect costs due to time lost from work for families and caregivers, and lifetime earnings lost due to premature death, and ultimately place significant social and financial burdens on families (Weiss & Sullivan, 2001). Thus, by increasing family competence and involvement in their child’s asthma management, providing care centered around the child and family needs, and improving accessibility and use of preventive services, including control-ler medications, care that meets the attributes of a medical home may enhance much needed patient and provider interactions, and contributes significantly in reducing the social and economic burdens of chronic conditions such as asthma (Cooley & McAllister, 2004). Although modest in scope, our findings suggest a potential for medical homes to contribute in improving the quality of care for children with chronic conditions such as asthma.

LimitationsLimitations of the present study include the measurement of the medical home con-cept, the use of self-reported measures, and the nature of survey data used. Using the more stringent “on every” rating approach, instead of the “across all,” may explain why only half of children with asthma qualified as having a medical home. As opera-tionalized by the AAP and in the NS-CSHCN, the “medical home” concept includes both individual practice and local ecological constructs. For example, an individual

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practice could well provide family-centered, culturally effective, and compassionate care, but fail to provide comprehensive care if there were problems obtaining referrals because of the nature of the child’s insurance (e.g., not all specialists will take Medic-aid) or the lack of specialists in the child’s community. Similarly, a practice could be doing well within its walls but have difficulty with the “communication between pro-viders” element of effective care coordination if specialists or hospitals in the area refuse to communicate. Next, there is the possibility that the “on every” approach to defining receipt of care in the medical care model has unanticipated effects. The apparent inverse association between severity of asthma and receipt of care in a medi-cal home model may be a measurement artifact: only moderate to severely affected children would need referrals, for example, and thus have the possibility of not meet-ing that part of the criteria. The pattern could also be a result of omitted variables (endogeneity), or could indicate that our theoretical model does not fully address all aspects of the relationship. Further investigations with other and larger datasets should attempt to confirm or refute these results.

Second, the present study analyzed cross-sectional data that do not allow for exam-ination of causal relationships or temporal associations. In addition, the NS-CSHCN relies on respondents’ reporting of the asthma status of their child without examining medical records. Other issues with parental report include recall and social desirability biases. Furthermore, although Bethell et al. (2004) have suggested that most of the components of the medical home can be assessed with parent-reported information, the NS-CSHCN does not capture the “continuity” and “accessibility” domains of the medical home. Similarly, parental patterns of health care use, another key enabling factor of child health service utilization (Mistry, Hoffmann, Yauck, & Brousseau, 2005), were not captured in the NS-CSHCN. However, the NS-CSHCN is one of only two national surveys that allow examining relationships between the medical home and important health services utilization behaviors and health outcomes among chil-dren with chronic conditions (Bethell et al., 2004).

Third, our findings represent only the national population of CSHCN, thus cannot be generalized to the general pediatric population or to the adult population. Neverthe-less our findings are important for people with chronic conditions of all ages, includ-ing children, youth, and adults. Both the children’s medical home and the more adult-oriented chronic care model emphasize the need for physicians to partner with patients, families, and other community resources in order to provide comprehensive primary care services and avoid complications, ED visits, and preventable hospitaliza-tions (AAP & Medical Home Initiatives for Children With Special Needs Project Advisory Committee, 2004; Kellerman & Kirk, 2007).

Implications for Policy and PracticeNumerous demonstration projects have reported the potential benefits of medical homes (Martin et al., 2007; Palfrey et al., 2004; Wang et al., 2005). However, progress in ensuring a medical home for children with chronic conditions has been slow

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(Strickland et al., 2009). The fragmented U.S. health care system makes it difficult to provide a medical home to chronically ill individuals. In addition, most efforts to improve the care provided to individuals with chronic conditions have focused on processes and overlooked staff attitudes. If the care coordination elements of the medi-cal care model are to be implemented, staff must be willing to depart with tradition and to collaborate across physical and organizational divides.

Therefore, families, health care professionals, insurers, and policymakers must explore new strategies to scale-up access to medical homes for all CSHCN. Promising strategies include, first, promoting nationally tested and validated models of medical home improvement among pediatric primary care providers, consumer advocates, and health plans through national awareness campaigns and continuing education curricu-lums. In offering patient/family-centered and greater coordination of care, medical home improvement initiatives may require restructuring pediatric primary care prac-tices, expanding hours of operation to accommodate the largest number of children, and adopting health information technologies. If general and specialist physicians adopt electronic/personal medical records and health information exchange within a region, care coordination for children with chronic conditions may be facilitated (AAP, Council on Clinical Information Technology, 2009). To that end, the AAP Center for Medical Home Initiatives, the Center for Medical Home Improvement, and the NAPNP, among others, offer practical resources.

A second strategy is the development of local quality improvement mentoring or tutoring collaboratives that also include hospital emergency departments. Since many asthmatic children in underserved areas are still relying on EDs for their health care needs, ED physicians should be partners in efforts to increase nonemergency ambula-tory care utilization with referral of those children to local primary care providers. A third strategy is to strengthen and expand the nation’s health care safety net to allow securing a medical home for those disadvantaged children with asthma.

Finally, the consistently documented association between health insurance and receipt of quality primary care in a medical home suggests the need for actions and reforms to maximize coverage but also to provide financial incentives to pediatric primary care practices through improved reimbursement mechanisms (AAP & Medi-cal Home Initiatives for Children With Special Needs Project Advisory Committee, 2004, AAP Committee on Adolescence and Committee on Child Health Financing, 2009; James & Rosenbaum, 2009).

Directions for Future ResearchFrom a measurement standpoint, future studies could assess the presence of a medical home under the perspective of a continuum of medical “homeness,” using nominal or ordinal measures rather than a dichotomous measure. While the latter is useful as a one-time indicator of the current medical home status, a nominal measure assessing the frequency of relevant combinations of the medical home domains could provide valuable information to practices on gaps that have to be closed to improve care for

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children with chronic conditions. Such measure could also be used to examine medical home components that are associated with greater health services utilization benefits, and guide incremental quality improvement efforts. An ordinal measure, on the other hand, would provide an assessment of the differential impact of fulfilling more com-ponents of a medical home.

Given the limitations of demonstration projects and cross-sectional studies, including the one presented here, in providing strong evidence supporting the assumption that med-ical homes provide integrated and better quality care and therefore lead to better out-comes for chronic conditions, it is imperative that future research attempt to establish causal relationships using long-term longitudinal designs. When feasible, the studies should extend the analysis to representative samples of the broader pediatric population.

Medical Home Componentsa

Survey Itemsb

Established relationship with a specific provider

Do you have one or more persons you think of as (child)’s personal doctor or nurse?

Accessible (Not asked)Family-centered During the past 12 months, how often did (child)’s doctors and other

health care providers spend enough time with (him/her)?During the past 12 months, how often did (child)’s doctors and other

health care providers listen carefully to you?In the past 12 months, how often did you get the specific information

you needed from (child)’s doctors and other health care providers?During the past 12 months, how often did (child)’s doctors and other

health care providers help you feel like a partner in (his/her) care?When (child) is seen by doctors or other health care providers, how

often are they sensitive to your family’s values and customs? Would you say never, sometimes, usually, or always?

During the past 12 months, did you (or child) need an interpreter to help speak with (his/her) doctors or other health care providers?

If yes, when you (or child) needed an interpreter, how often were you able to get someone other than a family member to help you speak with (his/her) doctors or other health care providers? Would you say never, sometimes, usually, or always?

Continuous (Not asked)

(continued)

AppendixData Items From the 2005-2006 National Survey of Children With Special Health Care Needs (NS-CHSCN) Used to Operationalize the Medical Home Concept

472 Medical Care Research and Review 67(4)

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interests with respect to the authorship and/or publication of this article.

Medical Home Componentsa

Survey Itemsb

Comprehensive During past 12 months, did (child) need a referral to see any doctors or receive any services?

If yes, was getting referrals a big problem, a small problem, or not a problem?

Is there a place that (child) usually goes when (he/she) is sick or you need advice about (his/her) health?

What kind of place is it (or what kind of place does (child) go to most often)?

Is there a place that (child) usually goes when (he/she) needs routine preventive care, such as a physical exam or a well-child check-up?

If yes, is the (place selected in C4Q0BR) that (child) goes to when (he/she) is sick the same place (child) usually goes for routine preventive care?

If no, what kind of place does (child) go for routine preventive care?Coordinated Does anyone help you arrange or coordinate (child)’s care among the

different doctors or services that (he/she) uses? During the past 12 months, have you felt that you could have used

extra help arranging or coordinating (child)’s care among these different health care providers or services?

If yes, during the past 12 months, how often did you get as much help as you wanted with arranging or coordinating (child)’s care?

Overall, are you very satisfied, somewhat satisfied, somewhat dissatisfied, or very dissatisfied with the communication among (child)’s doctors and other health care providers?

Do (child)’s doctors or other health care providers need to communicate with (his/her) school, early intervention program, child care providers, vocational education or rehabilitation program?

If yes, overall, are you very satisfied, somewhat satisfied, somewhat dissatisfied, or very dissatisfied with that communication?

Compassionate (Addressed in the family-centered domain questions)Culturally effective (Addressed in the family-centered domain questions)

a. From the American Academy of Pediatrics and Medical Home Initiatives for Children With Special Needs Project Advisory Committee (2004).b. From the survey instrument of the 2005-2006 NS-CSHCN (Blumberg et al., 2008).

Appendix (continued)

Diedhiou et al. 473

Funding

The author(s) received no financial support for the research and/or authorship of this article.

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