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Research Report

Internal Medicine–Pediatrics Physicians: Their Care of Children Versus Care of Adults

Freed, Gary L. MD, MPH; Fant, Kathryn E. MPH; Nahra, Tammie A. PhD; Wheeler, John R. C. PhD the Research Advisory Committee of the American Board of Pediatrics

Author Information

Abstract

Erratum

In the report by Freed and colleagues published last September, some key information was accidentally left out of the Method section.

The American Board of Internal Medicine (ABIM) maintains a combined list with the American Board of Pediatrics of all individuals who have successfully completed four years of medicine–pediatrics training. The report should have mentioned that as of May 12, 2003, when the study was carried out, there were 4,303 individuals who had completed training. Of these, 472 had completed at least three years of subspecialty training. In preparing the analysis that was reported, the authors used the data on all these 472 individuals. Of the remaining 3,831 individuals, the ABIM provided a random sample of 1,300. The sample was constructed using appropriate methodology and provided 80% power to detect a 10% difference both within the cartegories of each sample and between generalists and specialists. Responses were obtained from 805 of the generalist sample of 1,300, yielding a response rate of 62%, and from 274 of the 472 subspecialists sample, yielding a response rate of 58%.

Academic Medicine. 81(5):494, May 2006.

In 1967, the American Board of Pediatrics (ABP) and the American Board of Internal Medicine (ABIM) approved criteria for the combined training of physicians in both of their specialties. The combined training involves a four-year residency, with two years of training in each of the specialties of medicine and pediatrics. At the successful completion of training, physicians are eligible to sit for certifying examinations in each specialty.

The number of internal medicine–pediatrics residency programs has increased dramatically. From four programs offering nine positions in 1980, the discipline grew to 94 programs offering 406 positions in 2004. Likewise, the number of physicians choosing this pathway of training has increased over the years, from 724 enrolled in such residency programs in 1991 to 1,540 in 2003.1

Although this training pathway has existed for many years, little is known regarding the practice patterns of program graduates. This is especially true when examining the distinct practice patterns of generalists and subspecialists. Continued questions exist regarding the division of time between the care of children and adults and the influences on that division and other practice patterns. For those who pursue subspecialty training, decisions regarding whether to pursue this training in both internal medicine and pediatrics have an obvious impact on eventual practice patterns. Those who limit their subspecialty training to one or the other specialty may not fully utilize the unique knowledge and skill set they achieved during their residency training. Further, even those who pursue subspecialty training in both disciplines may in due course provide clinical care or conduct research predominately targeted to one age group or the other.

To assess the workforce contributions and patterns of delivery in the care of children and adults by internal medicine–pediatrics training program graduates, we undertook a survey study in 2003 of all physicians who had completed this training since the inception of the program. Principally, we sought to learn how internal medicine–pediatrics physicians allocate their practice time and resources between adult and child patients. Further, we investigated whether there are predictors of the extent to which a particular physician’s practice is more or less focused on children versus adults.

Because their practice patterns differ markedly, we report the results and present our discussion for generalists and subspecialists separately.

Method

Sample

The ABIM, with the assistance of the ABP, maintains a list of all physicians who have completed four years of training in an approved internal medicine–pediatrics residency program. The list includes all those who have completed training, whether or not they have applied to take the certifying examination in either or both specialties. There were 1,772 physicians in the list provided by the ABIM in 2003. Of these, 1,300 were classified as generalists (no further subspecialty training) and 472 were identified as subspecialists.

Survey instrument

Working with the ABP and the ABIM, we constructed two 25-item questionnaires, one for generalists and the other for subspecialists. Both questionnaires comprised questions with a mixture of fixed-choice, Likert-scale, and open-ended response options.

The primary outcome variable of interest for both the generalists and subspecialists was the proportion of clinical time spent in the care of infants, children, adults, or geriatric patients. For the subspecialists, an additional focus was whether subspecialty training took place in a department of pediatrics or internal medicine or both. Predictor variables assessed by both instruments included the adequacy of training received during residency among the patient age groups noted above, the ratio of inpatient versus outpatient care, and referrals. A final focus of both questionnaires was the proportion of time spent in continuing medical education and academic activities in either pediatrics or internal medicine, or in both of these specialties.

Questionnaire administration

The questionnaires were mailed to the 1,300 generalists and 472 subspecialists on the ABIM’s 2003 list. Two additional mailings went to the nonrespondents. The first two mailings were sent by first-class mail, and the third was sent by priority mail with a return receipt requested. A five-dollar bill was included in the first mailing as an incentive to complete the questionnaire. All the questionnaires were accompanied by a hand-signed cover letter from the principal investigator (GLF) explaining the nature of the study and the collaborative efforts of the ABP and ABIM in the project. A self-addressed postage paid envelope was included to facilitate return of the completed surveys.

Data analysis

Frequency distributions of all survey items were calculated. Next, chi-square statistics were used to determine levels of association between the outcome variable and the predictor variables. Scales were developed to assess ratios of care for all children 18 years or younger and all adults older than 18 years of age.

Finally, to investigate characteristics independently associated with a lack of clinical focus on children, we developed a logistical regression model. The dichotomous dependent variable in the model for generalists indicates whether the proportion of the physician’s patient visits were less than 50% for children 0–18 years of age, and for subspecialists, less than 25% for children 0–18 years of age.

The project was approved by the Institutional Review Board for the Protection of Human Subjects at the University of Michigan.

Results

Generalists

Response rate.

For 78 of the 1,300 generalist physicians in the original sample, U.S. mailing addresses could not be determined from the dataset or from Internet searches. Of the remainder, 97 questionnaires were sent back by the postal service as undeliverable; no responses were received for 294. The remaining 831 questionnaires were returned, of which 26 were ineligible due to the physician’s death or retirement or because he or she was in the wrong specialty. The 805 usable questionnaires gave us a response rate of 73%. Responses to the survey indicated that 79 physicians had at least 2 years of subspecialty training and were reclassified as subspecialists. This left a sample of 726 generalists for analysis. Analysis of demographic information comparing nonrespondents to respondents showed no differences between the groups.

Work patterns and environment.

A large majority (639; 88%) of the 726 internal medicine–pediatrics generalist physicians worked full-time at the time of our survey, and 574 (79%) spent at least three-quarters of their professional time in clinical care. Most (414; 57%) had no academic appointment or were adjunct faculty (167; 23%). Of those with academic appointments, 99 (68%) were in pediatrics and 103 (71%) were in internal medicine.

Gender issues.

A total of 421 (58%) of the respondents were men. The women respondents were more likely than the men to work part time: 73 (24%) versus 17 (4%); p < .001). The men were more likely to report that they were able to stay current in internal medicine: 278 (66%) versus 171 (56%); p = .006. No other differences were found between the women’s and men’s responses.

Focus of practice.

The vast majority of the internal medicine–pediatrics physicians who were generalists provided at least some care to all age ranges of patients including infants 0–1 year (624; 86%), children 2–11 years (639; 88%), adolescents 12–18 years (668; 92%), adults 19–65 years (661; 91%), and geriatric patients older than 65 years (646; 89%). However, the proportion of care provided to different age groups was not uniformly distributed. For some, the differences were substantial (see Table 1). Overall, these physicians provided more care to adults than to children.

Table 1
Table 1:
Focus of Practice of 726 Generalist Physicians Trained in Internal Medicine–Pediatrics, 2003

Few respondents reported they received referrals from pediatricians for the care of adults with chronic diseases of childhood, and few received many referrals from family physicians for the care of complex patients.

Most respondents stated that they provide at least some inpatient care. However, a substantial number (283; 39%) limited this portion of their practice to adults only. The majority of those who cared for both adults and children on an inpatient basis spent more time in the care of adults.

There was no difference in age range of patients for those physicians who had been in practice for fewer than, or greater than, five years.

Continuing medical education.

Our respondents were more likely to complete a greater proportion of their continuing medical education (CME) in internal medicine (312; 43%) or to divide their CME equally between pediatrics and internal medicine (334; 46%) than to focus a majority of their time on pediatrics (80; 11%). More of these same physicians reported that they were able to stay at least “somewhat” current in internal medicine (450; 62%) than they were in pediatrics (363; 50%).

Adequacy of residency training and its impact on practice.

When reporting on the adequacy of their residency training in preparing them for practice, respondents were more likely to feel better prepared for the care of adults and geriatric patients than for children. Specifically, only 50% (363) of respondents reported they were “very well” trained (ranking their training 4 on a four-point Likert scale where 4 = “very well” trained) in the care of newborns, 52% (378) in the care of toddlers/school-age children (≤11 years), and 45 % (327) in the care of adolescents (12–18 years). In contrast, 72% (523) of respondents reported they were “very well” trained in the care of adults and 56% (407) in the care of seniors (older than 65 years).

Those physicians who reported being “very well prepared” (ranking themselves 4 on a four-point Likert scale) for the care of infants (0–1 year) during residency were more likely than those who felt less well prepared (ranking their preparedness ≤3 on the same scale) to provide care to children once they were in practice. They were also more likely to report they kept current in pediatrics and spent more time in pediatric CME (see Table 2). This association remained consistent and statistically significant for those who reported being “very well prepared” in the care of children (1–11 years) and adolescents (12–18 years) (data not shown in the table). Similar associations existed for those who report being “very well prepared” for the care of adults (19–64 years), but the associations were not as robust (see Table 2).

Table 2
Table 2:
Perceptions of Generalist Physicians Trained in Internal Medicine–Pediatrics of Their Preparedness to Care for Children and Adults

Regression analysis.

Our model predicted the likelihood of not focusing a majority of clinical effort on the care of children. This was defined as denoting <50% of clinical effort in the care of children. Results demonstrated that those who felt less well-prepared to care for children were less likely to do so (OR = 0.68; 95% CI: 0.48, 0.96). Gender, part-time or full-time status, practice size, and practice setting were not significantly associated with lack of clinical focus on the care of children.

Subspecialists

Response rate.

For 19 of the 472 subspecialist physicians in the original sample, U.S. mailing addresses could not be determined from the dataset provided or from Internet searches. Of the remainder, 40 questionnaires were sent back by the postal service as undeliverable. An additional 20 potential participants were found to be ineligible due to their death or retirement or because they were in the wrong specialty. The 274 usable questionnaires gave us a response rate of 65%. Inclusion of the 79 respondents who were reclassified from generalists to subspecialists, noted above, left a sample of 333 for analysis.

Scope of subspecialty training.

Despite completing a combined internal medicine–pediatrics residency program, 180 (54%) of the respondents pursued subspecialty training in internal medicine only, while 127 (38%) completed a combined internal medicine–pediatrics subspecialty program. Eight percent received subspecialty training in pediatrics only.

Work patterns and environment.

Almost all (316; 95%) of the 333 internal medicine–pediatrics physicians worked full-time and approximately half (163; 49%) spent at least three-quarters of their professional time in clinical care. A majority (200; 60%) had some type of academic appointment: approximately one-third of those who had such appointments were adjunct faculty and one-third were full-time academic physicians. Of those with academic appointments, the majority (256; 77%) had appointments in departments of internal medicine, with only 153 (46%) in departments of pediatrics. A total of 113 (34%) had appointments in both departments. A greater proportion of respondents were fellows of the American College of Physicians (160; 48%) than of the American Academy of Pediatrics (123; 37%).

The overwhelming majority of the subspecialist respondents (250; 75%) did not focus their careers on research, reporting that they spend ≤ 20% of their time in such activities.

Gender issues.

Of all respondents, 230 (69%) were men. The men were more likely than the women to work full-time: 323 (97%) versus 300 (90%); p = .0008. The other gender differences found were the proportion of care provided to children and hospitalized adults.

Focus of practice.

The responding internal medicine–pediatrics subspecialist physicians were much more likely to focus their clinical efforts in the care of adults than of children. Fewer than half (143; 43%) stated that they provide any care to children aged 0–1 year. Regarding the provision of care to patients in other age ranges, 180 (54%) provided at least some care to children aged 2–11 years, while 233 (70%) provided at least some care to those 12–18 years of age. Provision of any care to adults was much more prevalent among these physicians, with 300 (90%) of respondents providing at least some care to 19–65-year-olds and 83% providing care to seniors (>65 years). Further, the proportion of care provided to adults was substantially more than that provided to children, with many respondents reporting that they markedly limit care to younger patients. Years of experience in practice was not found to be associated with a focus on a particular age range of patients.

A large number of the internal medicine–pediatrics subspecialists (246; 74%) provided care for adults with chronic diseases of childhood, and approximately half received referrals from pediatricians for the care of their patients transitioning to the adult age group.

Almost all respondents provided at least some inpatient care. However, a substantial number (130; 39%) limited this portion of their practice to adults only, while even more (233; 70%) provided no inpatient care to infants (0–1 month of age). The majority of those who provided inpatient care for both adults and children spent more time in the care of adults (see Table 3).

Table 3
Table 3:
Focus of Practice of 333 Subspecialist Physicians Trained in Internal Medicine–Pediatrics, 2003

Continuing medical education.

The internal medicine–pediatrics subspecialists were more likely to complete a greater proportion of their CME in internal medicine (233; 70%) than in pediatrics (37; 11%). The remainder (63; 19%) reported they equally divide their CME time between the two specialties.

Almost all of these physicians (300; 90%) reported that they are able to stay at least “somewhat” current in the field of internal medicine. However, fewer (167; 50%) reported they are able to do so for pediatrics.

Adequacy of residency training and its impact on current practice.

The subspecialists were more likely to report that their internal medicine–pediatrics residencies better prepared them for the care of adults than for the care of children. Most felt “very well” prepared to care for adults and elders. Fewer felt they were as well prepared in the care of newborns, toddlers, or adolescents. Specifically, only 163 (49%) of the 333 subspecialty respondents reported they were “very well” trained in the care of newborns, 173 (52%) in the care of toddlers/school-age children (≤11 years), and 183 (55%) in the care of adolescents (aged 12–18 years). In contrast, 256 (77%) of respondents reported they were “very well” trained in the care of adults and 226 (68%) in the care of seniors (>65 years).

Those physicians who reported being “very well prepared” (ranking themselves 4 on a four-point Likert scale) for the care of children (2–11 years of age) during residency were more likely than those who felt less well prepared (ranking their preparedness ≤3 on the same scale) to provide care to children of any age once in practice. They were also more likely to report they kept current in pediatrics and had an appointment in a pediatrics department. The majority of all respondents did more CME focused on internal medicine topics, and those who felt less well prepared for pediatric practice did an even greater proportion of their CME in internal medicine. These associations remained consistent and statistically significant for those who reported being “very well prepared” in the care of children and adolescents. Similar associations existed for those who reported being “very well prepared” for the care of adults and seniors (see Table 4).

Table 4
Table 4:
Perceptions of Subspecialist Physicians Trained in Internal Medicine–Pediatrics of Their Preparedness to Care for Children, Adults, and Seniors

Regression analysis.

Logistic regression demonstrated that the only significant predictor for limiting one’s practice to 25% or less of clinical effort in the care of children was whether the physician perceived that he or she was not very well prepared during internal medicine–pediatrics residency training for the care of children (odds ratio, 3.11; 95% confidence interval, 1.82–5.29). Components of the model not found to be significant were gender, part-time and full-time status, practice size, and practice setting.

Discussion

Generalists

The most significant finding of this portion of the study is that the responding generalist physicians who had been trained in internal medicine–pediatrics residencies were more likely to spend a majority of their professional time in the clinical care of adults and to limit their care of children. They were also more likely to complete CME regarding the care of adult patients and more likely to perceive that they stay more current in the care of adults than in the care of children. Future patterns of board recertification should be assessed in light of these findings to learn whether they are predictive of physicians’ subsequent patterns of care.

Most previous studies of the outcomes of internal medicine–pediatrics programs have involved reports by program directors on the practice choices of their former trainees and not reports by the graduates themselves.2 These studies’ findings have limited utility, as they are only proxies for reports of actual practice. The most recent study of program directors was conducted in 2003. It found that program directors reported 82% of their graduates from 1998 to 2002 were caring for both adults and children, but did not further delineate the proportion of time devoted to either age group.3 Importantly, this study also demonstrated that the completion rate for those entering internal medicine–pediatrics training was 91%, thus allaying any concerns regarding the attrition rate for this pathway.

The most recent comprehensive survey of internal medicine–pediatrics graduates was conducted a decade ago by Lannon et al.4 in 1995 and reported in 1999. This study of physicians who completed internal medicine–pediatrics training from 1985 to 1995 found that only 4% of respondents provided no care to children younger than ten years of age and that only 1% reported that 91% to 100% of their practice consisted of children younger than ten years. Our findings provide greater detail regarding the age breakdown of the patient population of the graduates of such programs and demonstrate a greater propensity of these physicians to care for more adults than children.

There is little research on the influence of training on subsequent practice. A notable exception is a 1990 study of internal medicine–pediatrics-trained physicians that asked program graduates to rank recommended changes in their training programs.5 Results did not indicate any perceived need to increase training in pediatric care; rather there was a desire to decrease the time spent in intensive care units and for greater emphasis on ambulatory care experiences. Interestingly, current requirements for internal medicine–pediatrics training include a limit of two months of adult intensive care experiences but require three months in the neonatal intensive care unit and one month in the pediatric intensive care unit.

These findings demonstrate the need for a more detailed and comprehensive assessment of the pediatrics training in these programs to understand the basis for the choices in practice made by these physicians. Focused research is needed on the nature of internal medicine–pediatrics training, including the process of selection of residents, to determine whether changes in the training process might affect the subsequent focus on adult care.

Our finding that a large segment of the responding internal medicine–pediatrics generalist physicians (312; 43%) completed more CME germane to internal medicine than to pediatrics is consistent with their reported focus on patients within certain age groups in their practices. However, the skew towards internal medicine in this regard is even greater than their clinical foci. It is unclear if this is due to a more attractive or available portfolio of CME options for internists, a perception that there is more effort required to stay current in internal medicine, or some other cause. However, the potential implication for this finding over time is that more of these physicians may believe they have not adequately maintained currency in pediatric care and will limit their care of children even further. Our results on existing self-perceptions already indicate evidence to this effect.

Many have postulated that physicians who had internal medicine–pediatrics training would provide a valuable resource for the care required by children with chronic diseases as they age and transition to adulthood. Others have assumed they might provide a resource for family physicians in the primary care of complex patients. However, our findings show that a majority of physicians with this training provide no such care and are not utilized by other physicians in this consultative manner. With the growing number of adult survivors of childhood illness, internal medicine–pediatrics graduates represent an underutilized portion of the physician workforce that can make unique contributions to this patient population.

Subspecialists

Like their generalist counterparts, the most significant finding among subspecialists is the degree to which they focused their training, practice, CME, and academic affiliations on adult patients. The process apparently begins in residency training with a perception by these physicians that they are better prepared to care for adults and seniors than for children. Among our respondents, the progression continued as 180 (54%) pursued subspecialty training in internal medicine only.

There is both a perceived and actual shortage of pediatric subspecialists.6 Although small in number, this particular group of subspecialist physicians, who report spending most of their professional time in clinical care, has the potential to make a substantial impact in providing care to this nation’s children.

Another important finding is that fewer than 25% of the subspecialists studied engaged in research for more than 20% of their professional time. Although this finding is likely not significantly different from corresponding findings for straight internal medicine or pediatrics training graduates, this particular cadre of physicians could probably offer unique insights into the nature of chronic disease and the adult manifestations of conditions that often or always begin in children, such as obesity, cystic fibrosis, depression, and diabetes. Our findings show that only a small proportion of these physicians entertain a research focus for their careers—thus, this distinct perspective may not often find its way to laboratory, clinical, or health services research.

Further, perceptions exist that as more children with chronic disease survive into adulthood, physicians who have had internal medicine–pediatrics training are the ideal providers to manage this transition.4 On the bright side, it is significant to note that 537 (74%) of the respondents reported that such care was a part of their practice.

Although we did not ask specifically whether the focus of research of our respondents was on children’s issues or whether their research was based in departments of internal medicine or pediatrics, we speculate that the patterns seen in both training and in clinical care are likely reflective of the research environment for these physicians as well. As such, we hypothesize that the bulk of the research conducted by these physicians is likely most relevant to adult issues. Considering the recognized problem of the diminutive amount of research conducted in pediatric settings or with a pediatric focus,7 the potential of internal medicine–pediatrics subspecialists to concentrate on research with that focus should be encouraged.

Conclusions

Given that the time devoted to internal medicine and to pediatrics during internal medicine–pediatrics residency programs is equivalent, the tendency for program graduates to focus more on the care of adults raises two related sets of questions. The first involves the reasons why this preference for adult care occurs. Several potential explanations merit further investigation and fit into two main groups: (1) market based and (2) training based.

One potential market-based explanation for the focus on adult care is the changing demography of the United States. As adults and seniors become a greater proportion of the population, it follows that they would become a greater proportion of the patient population of physicians whose patient panels span the life cycle.8 Interestingly, though, no differences in the adult-to-pediatric-care ratios were seen among those physicians who had been in practice for five years or more compared with their less experienced counterparts. This indicates that the practices of these physicians are not necessarily changing over time but are consistent in their representation of the population patterns of the United States. A recent study of family physician practice patterns demonstrated that over the decade of the 1990s, the proportion of the care they provided to children fell from 33% to just over 20%.9

A second potential market-based explanation is more serious and may partially explain this general trend. Because of differences in the common types of health insurance coverage between adults and children, the care of adults is often reimbursed at higher rates than is the care of children. Payment rates for routine visits and similar procedures performed on children are lower than those for adults in both public and private insurance markets. Additionally, adults in their working years are likely to be covered by private health insurance, and retired adults typically are enrolled in Medicare. Although Medicare may be the carrier providing the lowest payment for the care of adults, it is still substantially higher than Medicaid for children.10

With respect to potential training-based explanations of the focus of internal medicine–pediatricians on adult care, one could ask whether there is some particular aspect of the training of these physicians that fosters their greater focus on internal medicine. It is not surprising that physicians would be more likely to treat patients for whom they feel better prepared to deliver care. Future studies will need to determine why internal medicine–pediatrics-trained physicians responded to our questionnaire in this manner. It is possible that some of the differences in training between the internal medicine and pediatrics curricular components account for these differences. For example, the balance of time spent in intensive care or ambulatory settings differs between the two specialties. The degree of perceived preparedness for practice may be quite sensitive to this or other structural and programmatic variations between the training experiences in the two specialties. Alternatively, new physicians attracted into this joint program may have a greater interest in the adult population prior to entering training.

For the subspecialists, one other issue must be noted. As current requirements for combined subspecialty programs currently require four to five years of additional training rather than the two to three years required for just one of the disciplines, it is not surprising that so many of these physicians have chosen to limit their subspecialty training experience.11 However, now that this pattern has been identified, future studies must determine why a focus in internal medicine, relative to that of pediatrics, has become preferable for a majority of these physicians.

Physicians trained in internal medicine–pediatrics represent a valuable resource for the care of a wide range of patients. Efforts should be undertaken to further examine the nature of their training and the influences on their care delivery choices so that society realizes the greatest possible benefit from this rapidly growing discipline.

This report was funded by a grant from the American Board of Pediatrics Foundation.

References

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© 2005 Association of American Medical Colleges