- Email: [email protected]
Continuity of Care Is Associated With Well-Coordinated Care
Continuity of Care Is Associated With Well-Coordinated Care Dimitri A. Christakis, MD, MPH; Jeffrey A. Wright, MD; Frederick J. Zimmerman, PhD; Alta L. Bassett, MA; Frederick A. Connell, MD, MPH Context.—The importance of continuity of care as a means to promote care coordination remains controversial. Objective.—To determine if there is an association between having an objective measure of continuity of care and parental perception that care is well coordinated. Design.—Cross-sectional study. Setting and Population.—Seven hundred fifty-nine patients presenting to a primary care clinic completed surveys that included 5 items from the Components of Primary Care Index (CPCI) that relate to care coordination. Main Predictor Variable.—A continuity of care index (COC) that quantifies the degree of dispersion of care among providers. Main Outcome Measures.—Likelihood of parents reporting high scores on the care coordination domain as well as each of the 5 individual CPCI items related to care coordination. Results.—Greater continuity of care was associated with higher scores on the CPCI care-coordination domain (P , .001). Continuity of care was also specifically associated with increased odds of agreeing with all 5 individual CPCI items, including reporting that their child’s provider ‘‘always knows about care my child received in other places’’ (OR 3.97 [2.11–7.49]), ‘‘communicates with the other health care providers my child sees’’ (OR 2.98 [1.63–5.44]), ‘‘knows the results of my child’s visits to other doctors’’ (OR 2.02 [1.08–3.80]), and ‘‘always follows up on a problem my child has had, either at the next visit or by phone’’ (OR 6.20 [2.88–13.35]) and wanting one provider to coordinate all of the health care that the child receives (OR 3.28 [1.48–7.27]). Conclusions.—Greater continuity of primary care is associated with better care coordination as perceived by parents. Efforts to improve and maintain continuity may be justified. KEY WORDS: care
ambulatory care; care coordination; continuity of patient care; medical home; pediatrics; quality of
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he value of having a primary provider who coordinates and assures quality of care for children has been recognized for many decades and is viewed as a central component of health care, particularly for children with special health care needs.1–3 Most recently, this goal has been articulated in terms of the concept of a ‘‘medical home.’’4,5 Although the notion that consistent contact with a provider might improve care coordination is entirely plausible, empirical data as to the benefits of a medical home are generally lacking. Care coordination has been operationalized via case managers or the assignment of primary care providers; however, actually measuring the extent to which it is achieved is challenging because there is no gold standard for well-coordinated care.6,7 The Components of Primary Care Index (CPCI) is an
instrument that assesses several components of primary care from the patient’s perspective and includes a carecoordination domain.8 It was developed and tested on a large and diverse patient population, and questions related to care coordination were internally validated. The care coordination domain was subsequently found to be associated with patient satisfaction as well as with preference for a given physician. In previous studies we have found that consistent contact with a provider, continuity of care as measured by the continuity of care (COC) index,9 is associated with improved health outcomes and higher perceived quality of care.10–13 In this study, we aimed to test the hypothesis that greater COC indices would be associated with higher scores on the CPCI care coordination domain. METHODS This was a cross-sectional survey conducted in a pediatric clinic affiliated with the University of Washington. The Institutional Review Board of the University of Washington approved the study protocol.
From the Departments of Pediatrics (Dr Christakis and Dr Wright), Health Services (Dr Christakis, Dr Zimmerman, and Dr Connell), and Medical Education and Informatics (Dr Wright), University of Washington, Seattle, Wash; and the Child Health Institute, Seattle, Wash (Dr Christakis, Dr Wright, Dr Zimmerman, Ms Bassett, and Dr Connell). Address correspondence to Dimitri A. Christakis, MD, MPH, Child Health Institute, University of Washington, 6200 NE 74th St, Suite 210, Seattle, WA 98115-8160 (e-mail: [email protected]. edu). Received for publication August 12, 2002; accepted November 27, 2002. AMBULATORY PEDIATRICS Copyright q 2003 by Ambulatory Pediatric Association
Setting Participants were recruited from the Pediatric Care Center (PCC). The PCC is functionally 2 coexisting clinics: a primary care clinic staffed by 4 full-time clinicians (2 pediatricians and 2 nurse practitioners) and a resident teaching clinic precepted by pediatric faculty. All patients
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Table 1. Results of Provider CPCI Care Coordination Questions (each question ranges from 1 [strongly disagree) to 5 [strongly agree]) Question My child’s personal provider does not always know about care my child has received at other places. (reverse score) My child’s personal provider communicates with the other health care providers my child sees. My child’s personal provider knows the results fo my child’s visits to other doctors. My child’s personal provider always follows up on a problem my child has, either at the next visit or by phone. I want one provider to coordinate all of the health care my child receives.
Mean
Median
SD
N/A*
4.07
4.00
2.00
10 (3%)
3.91
4.00
.98
21 (6%)
4.03
4.00
.91
19 (5%)
4.15
4.00
.97
8 (2%)
4.35
4.00
.92
7 (2%)
*Respondents reported ‘‘My child does not have a personal provider for this particular item.’’
have an assigned primary provider within the PCC. The majority of patients (57%) are followed by and the majority of visits (60%) are made to the full-time clinicians. However, the same patients are seen by both groups of providers depending on availability. Patients therefore do crossover from one panel of providers to the other as needed. Subjects All English-speaking patients presenting to the clinic for either well or acute care who had made at least 3 prior visits were eligible for participation. Participants were given informed consent and those that agreed completed a brief questionnaire. Because care coordination is typically conceived of as being most relevant for patients who receive medical care at more than 1 site, we limited our analyses to patients who had received care from a provider who is not part of the PCC in the year prior to the completion of their survey. Included were all patients who had been hospitalized or had made at least 1 visit to the emergency department or to the after-hours clinic or had seen a subspecialist. This determination was made based on review of the electronic data system of the PCC, which tracks all authorized referrals. Questionnaire The questionnaire took approximately 10 minutes to complete and included all 5 items from the CPCI that relate to coordination of care (Table 1). In addition, parents supplied some demographic information, including race/ethnicity, identified primary provider, and household income. The questionnaire is available from the authors on request. Surveys were distributed by a research assistant in the waiting room prior to a visit and were collected before the patient was seen that day. Parents were compensated 1 dollar for their participation. Only people returning completed surveys were counted as participating in the study. Outcome Variables The CPCI has respondents reply using a 5-point Likert scale ranging from 1 5 strongly disagree to 5 5 strongly agree, with 3 being defined as neutral. Although 1 of the questions is phrased in the negative, we reverse scored it for the purposes of this analysis so that all responses are
consistent. The 5 questions included in the care coordination domain are reported in Table 1. Main Predictor Our primary predictor variable was an index of continuity of care. Several such indices have been developed to quantify continuity of care. We opted to employ the continuity of care (COC) index developed by Bice and Boxerman9 as we have done and described in prior studies. Briefly, the COC takes on values between 0 and 1. A value of 0 signifies maximum dispersion, which occurs when a different provider is seen for every visit. A value of 1 signifies minimum dispersion, which occurs when the same provider is seen at every visit. The PCC uses a computerized information system. This system is used for appointment scheduling as well as for billing. It reliably tracks which provider patients see at each visit. Because we were interested primarily in the association of continuity of primary care and parental perceived care coordination, we calculated patients’ COC indices based only on visits to primary care providers—both well-child and acute visits. Visits to specialists, subspecialists, or emergency departments were not included in computing the COC index. In addition, we excluded visits that were for procedures (eg, immunizations) only because these are medical assistant visits and do not entail contact with a provider. All visits made by the child to the clinic until the time of the survey administration were included in the calculation. Covariates We included race/ethnicity, number of visits at the time of survey, age of child, reported household income, and gender of child as covariates in our models. In addition, because the period of time that the children had been followed at the PCC might also confound our primary association of interest, we also included a variable, days at clinic, which was the number of days prior to the date that they completed the survey that they had been continuously enrolled at the PCC. Finally, because characteristics of individual providers may confound the association of interest, we included a dummy variable for each provider that participants identified as their child’s primary provider in all models.
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Table 2. Characteristics of Included Patients Variable
Mean (SD)
Age Male Number of visits Enrollment at PCC Care coordination score COC at time on survey
4.5 years (4.4) 47% 12.0 (8) 679 days (332) 19.92 (3.35) .46 (.27)
Income ($) ,10 000 10 000–$24 999 25 000–$49 999 50 000–$74 999 .75 000
38 64 87 53 107
continuity of care is mediated through all aspects of care coordination equally. For this analysis, we dichotomized each response into agree or strongly agree versus other. Logistic regression was then used to estimate the relationship between our dependent variables and our independent variables. All analyses were carried out using Stata version 7.0. RESULTS
(11%) (18%) (25%) (15%) (31%)
Statistical Analysis We conducted two analyses. First, we summed the responses from each of the individual items to form a composite score for the care coordination domain of the CPCI. As this score contained 5 items, each scored from 1 to 5, it has a potential range of 5–25. For this analysis, we performed linear regression to assess the independent association of each of our covariates with this outcome. Although the distribution of our outcome measure was not normal, linear regression can still be used in situations where the sample size is as large as ours.14 The resulting beta coefficients can be interpreted as a difference in the predicted score on the care coordination domain associated with a 1-unit change in the COC. We tested the possibility that there was effect modification by assigned provider type (resident vs full time clinician) by including an interaction term (provider type 3 COC) in our models. It was not significant and therefore was not retained, nor were the results stratified by provider type. Second, we were interested in exploring the independent association of continuity of care with each of the individual items of the care coordination domain. This analysis was important because it is unknown whether
A total of 1457 eligible patients were seen in clinic during the study period and 759 parents completed surveys (participation rate 52%). There were no significant differences between respondents and nonrespondents with respect to age, insurance type, provider, presence of asthma, use of medical services outside of the PCC, or race (see Tables 2 and 3). Three hundred seventy-one patients (49%) had received care outside of the PCC and comprised our analytic sample. The mean age of these patients was 4.5 years. They had made an average of 12 visits to the clinic and had been enrolled there for an average of just under 2 years. In general, the perceived care coordination was quite good. The mean score for the entire coordination domain was 19.92 (range 9–25). Mean scores for each of the items in the coordination domain ranged from 3.91 to 4.35 (Table 1). In the fully adjusted linear regression model, COC was associated with higher care coordination scores (B 5 3.79 [95% CI 2.27–5.31]). In the logistic regression models, COC was associated with statistically significantly higher CPCI ratings for all 5 items, including reporting that their child’s provider ‘‘always knows about care my child received in other places’’ (OR 3.97 [2.11–7.49]), ‘‘communicates with the other health care providers my child sees’’ (OR 2.98 [1.63–5.44]), ‘‘knows the results of my child’s visits to other doctors’’ (OR 2.02 [1.08–3.80]), and ‘‘always follows up on a problem my child has had, either at the next visit or by phone’’ (OR 6.20 [2.88–13.35]) and
Table 3. Logistic Regression Models of CPCI Care Coordination Items OR [95% CI]*
Variable
My child’s personal provider does not My child’s personal always know about provider communicates care my child has with the other health received in other care providers that my places. (reverse scored) child sees.
My child’s personal My child’s personal provider always follows provider knows the up on a problem my results of my child’s child has either at the visits to other doctors next visit or by phone.
I want one provider to coordinate all of the health care that my child receives.
COC at survey Days at clinic Number of visits Male child Non white
3.97 1.00 1.03 1.03 1.21
[2.11–7.49] [0.99–1.00] [1.00–1.06] [0.74–1.41] [0.85–1.46]
2.98 1.00 1.08 1.02 1.11
[1.63–5.44] [0.99–1.00] [1.04–1.11] [0.74–1.4] [0.76–1.43]
2.02 1.00 1.03 0.91 1.02
[1.08–3.80] [0.99–1.00] [1.00–1.06] [0.65–1.28] [0.80–1.23]
6.20 1.00 1.02 0.68 0.98
[2.88–13.55] [1.00–1.01] [0.98–1.04] [0.46–1.10] [0.46–1.35]
3.28 1.00 1.04 0.78 0.89
[1.48–7.27] [1.00–1.01] [1.00–1.08] [0.51–1.18] [0.67–1.13]
Income ($) ,10 000 10 000–24 999 25 000–49 999 50 000–74 999 .75 000
1.06 1.08 1.32 1.65
Ref [0.55–2.04] [0.58–2.06] [0.67–2.56] [0.90–3.05]
Ref 0.55 [0.27-1.10] 0.62 [0.31–1.19] 0.51 [0.26–1.03] 0.62 [0.33–1.18]
0.55 0.60 0.48 0.62
Ref [0.27–1.10] [0.29–1.10] [0.24–1.06] [0.30–1.41]
0.64 0.70 0.86 0.66
Ref [0.28–1.45] [0.31–1.54] [0.36–2.01] [0.30–1.41]
1.67 1.14 0.97 1.47
Ref [0.72–3.91] [0.54–2.47] [0.43–2.16] [0.70–3.11]
*All results are also adjusted for provider identified by respondent as their child’s personal one.
AMBULATORY PEDIATRICS
wanting one provider to coordinate all of the health care that the child receives (OR 3.28 [1.48–7.27]). These results are summarized in Table 3. DISCUSSION While most parents of children in this study rated the care coordination for their child fairly highly, we found a significant association between continuity of care and 4 specific items from the care coordination domain of the CPCI. The statistical significance of this association, as measured by the P values on the coefficients in our regression models, consistently exceeded that of other potentially important covariates, including number of visits, race, and income level. Advocates for medical homes have long argued that consistent contact with a provider will improve care coordination and ultimately health. This study lends some credence to that theory at least insofar as parental perceptions of care coordination are an accurate reflection of it. Unfortunately, current trends in health care in many important ways lean against the establishment of such homes. As many as 25% of patients are forced to switch providers every 2 years.15 In addition, other features of managed care, including the increasing size of provider groups and the use of ancillary providers, also may serve to diminish continuity of care. Some have argued that continuity of medical record may be as important as continuity of provider.16–19 We were unable to study the contribution of information to care coordination because all of our subjects were cared for in a single clinic. There are some limitations to this study that warrant consideration. First among them is the fact that it was conducted in a single clinic and must therefore be conservatively generalized. Although the sample of included patients was diverse, the extent to which they are representative of patients in other clinics is unknown. It should be noted, though, that our finding of a significant association between continuity of care and the care coordination domain of the CPCI is consistent with 1 other study.8 Second, the study was limited to English languagespeaking patients. The experiences of nonnative speakers, particularly those who rely on interpreted encounters, may very well be different. Third, we have measured parental assessment of care coordination rather than actual care coordination. Other methods have included physicians’ advance knowledge of care received elsewhere or role in arranging a visit.20,21 Although there is no consensus about how care coordination should be definitively measured, its putative benefit is that it will improve health outcomes. In other studies, we have found that continuity of care is associated with improved health outcomes, particularly for children with chronic disease, where care coordination may be especially important.11 Fourth, our participation rate was 52%, which might have led to a biased sample, though we found no evidence of this in comparing participants with nonparticipants. Finally, although we have found an association, we cannot draw causal inferences. In this case, it may be that parents value care coordination and therefore establish more consistent relationships with
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those providers who they deem to do it well. However, it is notable that the one item on the CPCI that was not significantly associated with continuity of care was ‘‘I want one provider to coordinate all of the health care my child receives,’’ which would argue against parental desires being determinative. Despite these limitations, there are some meaningful implications of our findings. Consistent provider contact is associated with improved care coordination. Parents in general do desire having a consistent provider, but that desire itself is not associated with achieving better continuity of care. Other means of improving continuity of care either via provider-initiated efforts or system change may be in order. ACKNOWLEDGMENTS The authors wish to thank the parents who participated in the survey as well as Cindy Farrell, Jamee Redmond, and Miryah Hibbard for their assistance with data collection. This study was funded in part by a Robert Wood Johnson Generalist Faculty Physician Scholars grant to Dimitri Christakis.
REFERENCES 1. Institute of Medicine. Primary Care: America’s Health in a New Era. Washington, DC: National Academy Press; 1996. 2. Stein RE. Challenges in long-term health care for children. Ambulatory Pediatr. 2001;1:280–288. 3. Forrest CB, Glade GB, Starfield B, et al. Gatekeeping and referral of children and adolescents to specialty care. Pediatrics. 1999;104(1 Pt 1):28–34. 4. Sia CC. Abraham Jacobi Award address, April 14, 1992, the medical home: pediatric practice and child advocacy in the 1990s. Pediatrics. 1992;90:419–423. 5. American Academy of Pediatrics Ad Hoc Task Force on Definition of the Medical Home: the medical home. Pediatrics. 1992;90:774. 6. Starfield BH, Simborg DW, Horn SD, Yourtee SA. Continuity and coordination in primary care: their achievement and utility. Med Care. 1976;14:625–636. 7. Barry TL, Davis DJ, Meara JG, Halvorson M. Case management: an evaluation at Childrens Hospital Los Angeles. Nursing Econ. 2002;20:22–27, 36. 8. Flocke SA. Measuring attributes of primary care: development of a new instrument. J Fam Pract. 1997;45:64–74. 9. Bice TW, Boxerman SB. A quantitative measure of continuity of care. Med Care. 1977;15:347–349. 10. Christakis DA, Mell L, Wright JA, et al. The association between greater continuity of care and timely measles-mumpsrubella vaccination. Am J Public Health. 2000;90:962–965. 11. Christakis DA, Mell L, Koepsell TD, et al. Association of lower continuity of care with greater risk of emergency department use and hospitalization in children. Pediatrics. 2001;107:524–529. 12. Christakis DA, Feudtner C, Pihoker C, Connell FA. Continuity and quality of care for children with diabetes who are covered by medicaid. Ambulatory Pediatr. 2001;1:99–103. 13. Christakis DA, Wright JA, Zimmerman FJ, et al. Continuity of care is associated with high-quality care by parental report. Pediatrics. 2002;109(4):e54. 14. Lumley T, Diehr P, Emerson S, Chen L. The importance of the normality assumption in large public health data sets. Annu Rev Public Health. 2002;23:151–169. 15. Flocke SA, Stange KC, Zyzanski SJ. The impact of insurance type and forced discontinuity on the delivery of primary care. J Fam Pract. 1997;45:129–135. 16. Mainous AG 3rd, Gill JM. The importance of continuity of care in the likelihood of future hospitalization: is site of care equivalent to a primary clinician? Am J Public Health. 1998;88:1539–1541. 17. Mainous AG, Hueston WJ, Love MM, Griffith CH. Access to
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care for the uninsured: is access to a physician enough? Am J Public Health. 1999;89:910–912. 18. Starfield B, Steinwachs D, Morris I, et al. Concordance between medical records and observations regarding information on coordination of care. Med Care. 1979;17:758–766. 19. Starfield B, Simborg D, Johns C, Horn S. Coordination of care and its relationship to continuity and medical records. Med Care. 1977;15:929–938.
AMBULATORY PEDIATRICS 20. Fletcher RH, O’Malley MS, Fletcher SW, et al. Measuring the continuity and coordination of medical care in a system involving multiple providers. Med Care. 1984;22:403–411. 21. Dietrich AJ, Nelson EC, Kirk JW, et al. Do primary physicians actually manage their patients’ fee-for-service care? JAMA. 1988;259:3145–3149.
ambulatory care; care coordination; continuity of patient care; medical home; pediatrics; quality of
Ambulatory Pediatrics 2003;3:82 86
T
he value of having a primary provider who coordinates and assures quality of care for children has been recognized for many decades and is viewed as a central component of health care, particularly for children with special health care needs.1–3 Most recently, this goal has been articulated in terms of the concept of a ‘‘medical home.’’4,5 Although the notion that consistent contact with a provider might improve care coordination is entirely plausible, empirical data as to the benefits of a medical home are generally lacking. Care coordination has been operationalized via case managers or the assignment of primary care providers; however, actually measuring the extent to which it is achieved is challenging because there is no gold standard for well-coordinated care.6,7 The Components of Primary Care Index (CPCI) is an
instrument that assesses several components of primary care from the patient’s perspective and includes a carecoordination domain.8 It was developed and tested on a large and diverse patient population, and questions related to care coordination were internally validated. The care coordination domain was subsequently found to be associated with patient satisfaction as well as with preference for a given physician. In previous studies we have found that consistent contact with a provider, continuity of care as measured by the continuity of care (COC) index,9 is associated with improved health outcomes and higher perceived quality of care.10–13 In this study, we aimed to test the hypothesis that greater COC indices would be associated with higher scores on the CPCI care coordination domain. METHODS This was a cross-sectional survey conducted in a pediatric clinic affiliated with the University of Washington. The Institutional Review Board of the University of Washington approved the study protocol.
From the Departments of Pediatrics (Dr Christakis and Dr Wright), Health Services (Dr Christakis, Dr Zimmerman, and Dr Connell), and Medical Education and Informatics (Dr Wright), University of Washington, Seattle, Wash; and the Child Health Institute, Seattle, Wash (Dr Christakis, Dr Wright, Dr Zimmerman, Ms Bassett, and Dr Connell). Address correspondence to Dimitri A. Christakis, MD, MPH, Child Health Institute, University of Washington, 6200 NE 74th St, Suite 210, Seattle, WA 98115-8160 (e-mail: [email protected]. edu). Received for publication August 12, 2002; accepted November 27, 2002. AMBULATORY PEDIATRICS Copyright q 2003 by Ambulatory Pediatric Association
Setting Participants were recruited from the Pediatric Care Center (PCC). The PCC is functionally 2 coexisting clinics: a primary care clinic staffed by 4 full-time clinicians (2 pediatricians and 2 nurse practitioners) and a resident teaching clinic precepted by pediatric faculty. All patients
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Table 1. Results of Provider CPCI Care Coordination Questions (each question ranges from 1 [strongly disagree) to 5 [strongly agree]) Question My child’s personal provider does not always know about care my child has received at other places. (reverse score) My child’s personal provider communicates with the other health care providers my child sees. My child’s personal provider knows the results fo my child’s visits to other doctors. My child’s personal provider always follows up on a problem my child has, either at the next visit or by phone. I want one provider to coordinate all of the health care my child receives.
Mean
Median
SD
N/A*
4.07
4.00
2.00
10 (3%)
3.91
4.00
.98
21 (6%)
4.03
4.00
.91
19 (5%)
4.15
4.00
.97
8 (2%)
4.35
4.00
.92
7 (2%)
*Respondents reported ‘‘My child does not have a personal provider for this particular item.’’
have an assigned primary provider within the PCC. The majority of patients (57%) are followed by and the majority of visits (60%) are made to the full-time clinicians. However, the same patients are seen by both groups of providers depending on availability. Patients therefore do crossover from one panel of providers to the other as needed. Subjects All English-speaking patients presenting to the clinic for either well or acute care who had made at least 3 prior visits were eligible for participation. Participants were given informed consent and those that agreed completed a brief questionnaire. Because care coordination is typically conceived of as being most relevant for patients who receive medical care at more than 1 site, we limited our analyses to patients who had received care from a provider who is not part of the PCC in the year prior to the completion of their survey. Included were all patients who had been hospitalized or had made at least 1 visit to the emergency department or to the after-hours clinic or had seen a subspecialist. This determination was made based on review of the electronic data system of the PCC, which tracks all authorized referrals. Questionnaire The questionnaire took approximately 10 minutes to complete and included all 5 items from the CPCI that relate to coordination of care (Table 1). In addition, parents supplied some demographic information, including race/ethnicity, identified primary provider, and household income. The questionnaire is available from the authors on request. Surveys were distributed by a research assistant in the waiting room prior to a visit and were collected before the patient was seen that day. Parents were compensated 1 dollar for their participation. Only people returning completed surveys were counted as participating in the study. Outcome Variables The CPCI has respondents reply using a 5-point Likert scale ranging from 1 5 strongly disagree to 5 5 strongly agree, with 3 being defined as neutral. Although 1 of the questions is phrased in the negative, we reverse scored it for the purposes of this analysis so that all responses are
consistent. The 5 questions included in the care coordination domain are reported in Table 1. Main Predictor Our primary predictor variable was an index of continuity of care. Several such indices have been developed to quantify continuity of care. We opted to employ the continuity of care (COC) index developed by Bice and Boxerman9 as we have done and described in prior studies. Briefly, the COC takes on values between 0 and 1. A value of 0 signifies maximum dispersion, which occurs when a different provider is seen for every visit. A value of 1 signifies minimum dispersion, which occurs when the same provider is seen at every visit. The PCC uses a computerized information system. This system is used for appointment scheduling as well as for billing. It reliably tracks which provider patients see at each visit. Because we were interested primarily in the association of continuity of primary care and parental perceived care coordination, we calculated patients’ COC indices based only on visits to primary care providers—both well-child and acute visits. Visits to specialists, subspecialists, or emergency departments were not included in computing the COC index. In addition, we excluded visits that were for procedures (eg, immunizations) only because these are medical assistant visits and do not entail contact with a provider. All visits made by the child to the clinic until the time of the survey administration were included in the calculation. Covariates We included race/ethnicity, number of visits at the time of survey, age of child, reported household income, and gender of child as covariates in our models. In addition, because the period of time that the children had been followed at the PCC might also confound our primary association of interest, we also included a variable, days at clinic, which was the number of days prior to the date that they completed the survey that they had been continuously enrolled at the PCC. Finally, because characteristics of individual providers may confound the association of interest, we included a dummy variable for each provider that participants identified as their child’s primary provider in all models.
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Table 2. Characteristics of Included Patients Variable
Mean (SD)
Age Male Number of visits Enrollment at PCC Care coordination score COC at time on survey
4.5 years (4.4) 47% 12.0 (8) 679 days (332) 19.92 (3.35) .46 (.27)
Income ($) ,10 000 10 000–$24 999 25 000–$49 999 50 000–$74 999 .75 000
38 64 87 53 107
continuity of care is mediated through all aspects of care coordination equally. For this analysis, we dichotomized each response into agree or strongly agree versus other. Logistic regression was then used to estimate the relationship between our dependent variables and our independent variables. All analyses were carried out using Stata version 7.0. RESULTS
(11%) (18%) (25%) (15%) (31%)
Statistical Analysis We conducted two analyses. First, we summed the responses from each of the individual items to form a composite score for the care coordination domain of the CPCI. As this score contained 5 items, each scored from 1 to 5, it has a potential range of 5–25. For this analysis, we performed linear regression to assess the independent association of each of our covariates with this outcome. Although the distribution of our outcome measure was not normal, linear regression can still be used in situations where the sample size is as large as ours.14 The resulting beta coefficients can be interpreted as a difference in the predicted score on the care coordination domain associated with a 1-unit change in the COC. We tested the possibility that there was effect modification by assigned provider type (resident vs full time clinician) by including an interaction term (provider type 3 COC) in our models. It was not significant and therefore was not retained, nor were the results stratified by provider type. Second, we were interested in exploring the independent association of continuity of care with each of the individual items of the care coordination domain. This analysis was important because it is unknown whether
A total of 1457 eligible patients were seen in clinic during the study period and 759 parents completed surveys (participation rate 52%). There were no significant differences between respondents and nonrespondents with respect to age, insurance type, provider, presence of asthma, use of medical services outside of the PCC, or race (see Tables 2 and 3). Three hundred seventy-one patients (49%) had received care outside of the PCC and comprised our analytic sample. The mean age of these patients was 4.5 years. They had made an average of 12 visits to the clinic and had been enrolled there for an average of just under 2 years. In general, the perceived care coordination was quite good. The mean score for the entire coordination domain was 19.92 (range 9–25). Mean scores for each of the items in the coordination domain ranged from 3.91 to 4.35 (Table 1). In the fully adjusted linear regression model, COC was associated with higher care coordination scores (B 5 3.79 [95% CI 2.27–5.31]). In the logistic regression models, COC was associated with statistically significantly higher CPCI ratings for all 5 items, including reporting that their child’s provider ‘‘always knows about care my child received in other places’’ (OR 3.97 [2.11–7.49]), ‘‘communicates with the other health care providers my child sees’’ (OR 2.98 [1.63–5.44]), ‘‘knows the results of my child’s visits to other doctors’’ (OR 2.02 [1.08–3.80]), and ‘‘always follows up on a problem my child has had, either at the next visit or by phone’’ (OR 6.20 [2.88–13.35]) and
Table 3. Logistic Regression Models of CPCI Care Coordination Items OR [95% CI]*
Variable
My child’s personal provider does not My child’s personal always know about provider communicates care my child has with the other health received in other care providers that my places. (reverse scored) child sees.
My child’s personal My child’s personal provider always follows provider knows the up on a problem my results of my child’s child has either at the visits to other doctors next visit or by phone.
I want one provider to coordinate all of the health care that my child receives.
COC at survey Days at clinic Number of visits Male child Non white
3.97 1.00 1.03 1.03 1.21
[2.11–7.49] [0.99–1.00] [1.00–1.06] [0.74–1.41] [0.85–1.46]
2.98 1.00 1.08 1.02 1.11
[1.63–5.44] [0.99–1.00] [1.04–1.11] [0.74–1.4] [0.76–1.43]
2.02 1.00 1.03 0.91 1.02
[1.08–3.80] [0.99–1.00] [1.00–1.06] [0.65–1.28] [0.80–1.23]
6.20 1.00 1.02 0.68 0.98
[2.88–13.55] [1.00–1.01] [0.98–1.04] [0.46–1.10] [0.46–1.35]
3.28 1.00 1.04 0.78 0.89
[1.48–7.27] [1.00–1.01] [1.00–1.08] [0.51–1.18] [0.67–1.13]
Income ($) ,10 000 10 000–24 999 25 000–49 999 50 000–74 999 .75 000
1.06 1.08 1.32 1.65
Ref [0.55–2.04] [0.58–2.06] [0.67–2.56] [0.90–3.05]
Ref 0.55 [0.27-1.10] 0.62 [0.31–1.19] 0.51 [0.26–1.03] 0.62 [0.33–1.18]
0.55 0.60 0.48 0.62
Ref [0.27–1.10] [0.29–1.10] [0.24–1.06] [0.30–1.41]
0.64 0.70 0.86 0.66
Ref [0.28–1.45] [0.31–1.54] [0.36–2.01] [0.30–1.41]
1.67 1.14 0.97 1.47
Ref [0.72–3.91] [0.54–2.47] [0.43–2.16] [0.70–3.11]
*All results are also adjusted for provider identified by respondent as their child’s personal one.
AMBULATORY PEDIATRICS
wanting one provider to coordinate all of the health care that the child receives (OR 3.28 [1.48–7.27]). These results are summarized in Table 3. DISCUSSION While most parents of children in this study rated the care coordination for their child fairly highly, we found a significant association between continuity of care and 4 specific items from the care coordination domain of the CPCI. The statistical significance of this association, as measured by the P values on the coefficients in our regression models, consistently exceeded that of other potentially important covariates, including number of visits, race, and income level. Advocates for medical homes have long argued that consistent contact with a provider will improve care coordination and ultimately health. This study lends some credence to that theory at least insofar as parental perceptions of care coordination are an accurate reflection of it. Unfortunately, current trends in health care in many important ways lean against the establishment of such homes. As many as 25% of patients are forced to switch providers every 2 years.15 In addition, other features of managed care, including the increasing size of provider groups and the use of ancillary providers, also may serve to diminish continuity of care. Some have argued that continuity of medical record may be as important as continuity of provider.16–19 We were unable to study the contribution of information to care coordination because all of our subjects were cared for in a single clinic. There are some limitations to this study that warrant consideration. First among them is the fact that it was conducted in a single clinic and must therefore be conservatively generalized. Although the sample of included patients was diverse, the extent to which they are representative of patients in other clinics is unknown. It should be noted, though, that our finding of a significant association between continuity of care and the care coordination domain of the CPCI is consistent with 1 other study.8 Second, the study was limited to English languagespeaking patients. The experiences of nonnative speakers, particularly those who rely on interpreted encounters, may very well be different. Third, we have measured parental assessment of care coordination rather than actual care coordination. Other methods have included physicians’ advance knowledge of care received elsewhere or role in arranging a visit.20,21 Although there is no consensus about how care coordination should be definitively measured, its putative benefit is that it will improve health outcomes. In other studies, we have found that continuity of care is associated with improved health outcomes, particularly for children with chronic disease, where care coordination may be especially important.11 Fourth, our participation rate was 52%, which might have led to a biased sample, though we found no evidence of this in comparing participants with nonparticipants. Finally, although we have found an association, we cannot draw causal inferences. In this case, it may be that parents value care coordination and therefore establish more consistent relationships with
Continuity of Care
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those providers who they deem to do it well. However, it is notable that the one item on the CPCI that was not significantly associated with continuity of care was ‘‘I want one provider to coordinate all of the health care my child receives,’’ which would argue against parental desires being determinative. Despite these limitations, there are some meaningful implications of our findings. Consistent provider contact is associated with improved care coordination. Parents in general do desire having a consistent provider, but that desire itself is not associated with achieving better continuity of care. Other means of improving continuity of care either via provider-initiated efforts or system change may be in order. ACKNOWLEDGMENTS The authors wish to thank the parents who participated in the survey as well as Cindy Farrell, Jamee Redmond, and Miryah Hibbard for their assistance with data collection. This study was funded in part by a Robert Wood Johnson Generalist Faculty Physician Scholars grant to Dimitri Christakis.
REFERENCES 1. Institute of Medicine. Primary Care: America’s Health in a New Era. Washington, DC: National Academy Press; 1996. 2. Stein RE. Challenges in long-term health care for children. Ambulatory Pediatr. 2001;1:280–288. 3. Forrest CB, Glade GB, Starfield B, et al. Gatekeeping and referral of children and adolescents to specialty care. Pediatrics. 1999;104(1 Pt 1):28–34. 4. Sia CC. Abraham Jacobi Award address, April 14, 1992, the medical home: pediatric practice and child advocacy in the 1990s. Pediatrics. 1992;90:419–423. 5. American Academy of Pediatrics Ad Hoc Task Force on Definition of the Medical Home: the medical home. Pediatrics. 1992;90:774. 6. Starfield BH, Simborg DW, Horn SD, Yourtee SA. Continuity and coordination in primary care: their achievement and utility. Med Care. 1976;14:625–636. 7. Barry TL, Davis DJ, Meara JG, Halvorson M. Case management: an evaluation at Childrens Hospital Los Angeles. Nursing Econ. 2002;20:22–27, 36. 8. Flocke SA. Measuring attributes of primary care: development of a new instrument. J Fam Pract. 1997;45:64–74. 9. Bice TW, Boxerman SB. A quantitative measure of continuity of care. Med Care. 1977;15:347–349. 10. Christakis DA, Mell L, Wright JA, et al. The association between greater continuity of care and timely measles-mumpsrubella vaccination. Am J Public Health. 2000;90:962–965. 11. Christakis DA, Mell L, Koepsell TD, et al. Association of lower continuity of care with greater risk of emergency department use and hospitalization in children. Pediatrics. 2001;107:524–529. 12. Christakis DA, Feudtner C, Pihoker C, Connell FA. Continuity and quality of care for children with diabetes who are covered by medicaid. Ambulatory Pediatr. 2001;1:99–103. 13. Christakis DA, Wright JA, Zimmerman FJ, et al. Continuity of care is associated with high-quality care by parental report. Pediatrics. 2002;109(4):e54. 14. Lumley T, Diehr P, Emerson S, Chen L. The importance of the normality assumption in large public health data sets. Annu Rev Public Health. 2002;23:151–169. 15. Flocke SA, Stange KC, Zyzanski SJ. The impact of insurance type and forced discontinuity on the delivery of primary care. J Fam Pract. 1997;45:129–135. 16. Mainous AG 3rd, Gill JM. The importance of continuity of care in the likelihood of future hospitalization: is site of care equivalent to a primary clinician? Am J Public Health. 1998;88:1539–1541. 17. Mainous AG, Hueston WJ, Love MM, Griffith CH. Access to
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AMBULATORY PEDIATRICS 20. Fletcher RH, O’Malley MS, Fletcher SW, et al. Measuring the continuity and coordination of medical care in a system involving multiple providers. Med Care. 1984;22:403–411. 21. Dietrich AJ, Nelson EC, Kirk JW, et al. Do primary physicians actually manage their patients’ fee-for-service care? JAMA. 1988;259:3145–3149.