One’s usual source of care (USC) is “the particular medical professional, doctor’s office, clinic, health center, or other place where a person would usually go if sick or in need of advice about his or her health (1).” A growing body of research indicates that having a USC improves timely access to medical care, improves quality of care received, and results in improved health status (23456). Primary care can be identified as the specific set of health care functions served by a USC. Under this definition, patients are said to receive primary care when they have a USC and when this source serves four essential functions (7): first-contact care for new health problems, comprehensive care for the majority of health problems, long-term person-focused care, and care coordination across providers (8). Primary care researchers have focused on the importance of the regular doctor in primary care, finding it associated with improved access (9101112).

Although many studies have investigated the effect of having a USC on an individual’s care-seeking behavior, most do not distinguish between having a regular doctor and having a regular site. Distinctions between the two, we inferred, would contain a valuable implication especially in Korea where there was no patient enrolment in primary care. But we did not find the Korean studies in the scientific literature about it. In the United States, one study that used data from the 1987 Medical Expenditure Panel Survey (MEPS) found that persons with a regular doctor had better access to primary care than did those with a regular site but not doctor (13). Those authors also found that the comparative advantage of having a regular doctor over having a regular site was diminished when non-mainstream sites (emergency rooms [ERs], outpatient departments, and family health centers) were excluded from the analysis. Another study found that the contribution of a regular doctor to consumers’ perceptions of access was marginal when optimal primary care was provided at a site (14). Another study that used the 1996 MEPS revealed that promoting a stable physician-patient relationship can improve patients’ timely receipt of clinical prevention but that the comparative advantage of having a regular doctor over having a regular site appeared only in blood pressure and cholesterol level checkups (5).

Korea has a very weak primary care infrastructure because of the health care system characterized by private-sector dominance in health care facilities (> 90%); nearly all payments are based on fee-for-service; and there has been no consensus on the concept of primary care; this is the case even though universal health insurance has been in place since 1989 and family medicine as a specialty was officially incepted for providing primary care services in 1986 (1516). The National Health Insurance (NHI) has not promoted having a USC. In the context of these characteristics, among the 34 Organisation for Economic Co-operation and Development (OECD) member countries, in 2013, Korea showed the highest frequency of doctors’ consultations per capita per year (14.6 vs. OECD average 6.7) and the highest number of hospital beds per capita, tied with Japan (11 beds or more per 1,000 people) (17). The rate of having a USC among Korean adults was another extreme index. A study that used data from the 2001 Korean National Health and Nutrition Examination Survey reported that the percentage of adults who responded that they had a place as a USC was very low (29.9%) (18), compared with data from other industrialized countries in an international survey conducted by the Commonwealth Fund in 2007, e.g., 96% in Australia, 91% in Canada, 95% in Germany, 100% in The Netherlands, 95% in New Zealand, 97% in the United Kingdom, and 90% in the United States (19).

The percentage of those who had a physician as a USC in Korea had been unknown until 2012, when the Korea Health Panel (KHP) survey included questions regarding a usual physician. The rate was only 13.9% for a physician with a place (vs. 21.5% for a physician or a place), which was reported at a 2015 academic conference on the KHP survey (20). In this study, we attempted to focus on having a physician with a place over only a place and to identify associated sociodemographic and health status factors in health care use (hospital admissions, emergency department visits) and out-of-pocket medical costs using data from the 2012 KHP survey.

The KHP data are collected in a national database established by a consortium of the Korea Institute for Health and Social Affairs and the National Health Insurance Services. The KHP uses a stratified multistage probability sampling design according to region and residence in order to select nationwide subjects from the 2005 Korea Census. The data were initially collected from 7,009 households and 21,283 individuals in 2008, with 5,434 households and 15,872 individuals remaining in 2012. It contains detailed information on families and individuals from a nationally representative sample of households on the following: demographic characteristics, income, savings and expenses, employment, housing, chronic conditions, use of medical services, medications, charges and sources of payments, private health insurance, pregnancy and delivery, elder care, and health behaviors and awareness.

As far as the authors know, this study was the first in Korea to analyze the association of having a physician with a place (vs. having only a place) as a USC with health care utilization in Korea using one of nationally representative data from the 2012 KHP survey. This study added evidence that having a physician with a place rather than having only a place would be more beneficial in hospital admissions and ER visits.

In Korea, there has been an official referral system for over two decades. In reality, however, referral letters are frequently issued at a patient’s demand rather than based on the physician’s medical decisions (23). In addition, there are a number of bypass routes to access to tertiary care hospitals; one is health screening centers, which distribute patients directly to disease specialists based on the screened health problem (24). There has been a tremendous increase in the number of these centers since 2000, when the government health screening policy expanded the target population and many people began to get periodic medical screenings at no out-of-pocket cost. Employers are obliged to have their employees screened annually (25). As a result, among those who receive health screens, there are more people who are insured through the workplace than self-employed individuals and more men than women. Doctor-patient relationships in primary care have been disrupted by these health screenings because they are driven by market mechanisms and are not coordinated by primary care physicians. This inadvertent result of the health screening policy may at least in part explain this study’s result that females (vs. males) and those who have self-employed (vs. employees) health insurance have high odds for having a usual physician.

The frequency of outpatient visit was included to adjust health status in this study, which had no statistical significance in association with having any types of USC. This result disclosed the fact that usual providers in Korea might be poor in coordination function for their patients to visit hospital outpatient departments timely and adequately. The 2015 academic conference on the KHP survey, mentioned above, reported only 34.5% answered positively regarding the coordination of care they experienced from their usual physicians in the 2012 KHP (20). It was contrasted explicitly with data from other industrialized countries. According to the Commonwealth Fund 2007 International Health Policy Survey, the proportions of those reported receiving coordinated care always or often were 70% in Australia, 69% in the United States, 67% in Canada and Germany, 60% in New Zealand, 58% in the United Kingdom, and 55% in the Netherlands (19).

This study revealed that having a physician with a place (vs. only a place) as a USC was associated with fewer hospital admissions and ER visits after controlling for sociodemographic and health status factors. That is, having a physician is more beneficial in using health care in Korea than is having a place as a USC. Lack of a physician as a USC not only interrupts continuity of care but also imposes a significant barrier to receiving medical treatment, which can result in negative health outcomes. In the United States, an analysis of paid claims to the Delaware Medicaid program during a 2-year period showed that after controlling for demographics, number of ambulatory visits, and case mix, higher provider continuity was associated with a lower likelihood of hospitalization for any condition (OR = 0.56; 95% CI, 0.46–0.69) (26). In the United Kingdom, greater continuity of care with a GP was associated with lower risk of admission (27). Primary care in the United States and most countries in Asia is provided by a variety of doctors. In one population-based, cross-sectional telephone survey (2007–2008) in Hong Kong, 60.2% (n = 1,896) of respondents had a regular primary care doctor out of 3,148 subjects. Controlling for socio-demographics and health status, those who reported a family doctor as a USC had lower ORs of using ER services and being admitted to hospital than those who used other regular doctors (0.62 or 0.51) or who did not have a regular doctor (0.48 and 0.46, respectively) (28). In the United Kingdom, quality improvement in primary care with the introduction of a major national pay-for-performance scheme was associated with a decrease of 8.0% in emergency admissions for incentivized conditions compared with conditions that were not incentivized over 13 years (1998–2011) (29).

Generally, having a USC is associated with lower costs of care. Longer relationships between patients and their usual physicians are associated with lower rates of hospital admission and lower total costs of care among Medicare beneficiaries in the United States (30). In the Korean health care system, in which the proportion of those who have a USC is very low and the proportion of out-of-pocket costs in total health expenditures is very high (36.9%, the second highest in the 34 OECD member countries based on 2013 OECD Health Statistics) (17), those who have a regular physician have more health problems but also more timely (sometimes frequently under fee-for-service) access to their physicians’ ambulatory care facilities than do those who don’t have a USC, which could incur higher medical care costs, as was seen in this study.

A number of limitations should be noted. The KHP data do not differentiate primary care physicians from medical specialists, and the authors could not analyze the discrete nature of the primary care. Another limitation might relate to adjusting for health status or severity of chronic disease in the regression models, though the authors added subjective health status and frequency of outpatient visits as well as the presence of chronic disease. The third limitation was that the discriminative ability (C statistics) was relatively low (< 0.7) in the logistic regression models to analyze the associations of having a USC with hospital admissions and ER visits in this study. This might be due to limitations of the model; e.g., if there were an insufficient number of predictors or the predictors had been dichotomized for simplicity (22). The fourth limitation was the fact that this study used the cross-sectional data of the 2012 KHP, which allowed only for showing associations, not the causal relationships, of having a physician plus place (rather than only a place) as a USC with health care use and its costs. If the items related to a place and a physician as a USC are included repeatedly in the future KHP surveys, panel data analysis can be used to prove causal relationships with health care use and its associated costs.

In conclusion, among those who had a USC in the Korean health care system, having a physician with a place (compared with having only a place) as a USC was associated with fewer hospital admissions and ER visits though was not different in medical care costs. Policies that promote having a physician as a USC may reduce avoidable hospital admissions and ER visits and would be better for the Korean health care system.