The distribution of family physicians in Japan significantly shifted to rural areas compared with the distribution of family physicians in the U.S.; in both countries other specialists concentrated heavily in urban areas. If the proportion of family physicians in Japan increased to that in the U.S., the geographic maldistribution of all physicians improved substantially. These results have two implications. One implication is that the distribution of family physicians is roughly equitable among the population in any society compared with that of other specialists, but the distribution can be biased substantially to rural areas in a society in which family medicine is emerging. The second implication is that, based on the rural-biased distribution of family physicians in Japan, increasing the number of family physicians can resolve the urban-rural imbalance in the supply of physicians.
Family physicians distribute equally among population in most societies with a mature primary care system. One reason for the equal distribution is that family physicians can make the most of their expertise in the rural healthcare environment [15, 16]. In urban areas, there are many more medical facilities, including highly specialized ones, and the geographic accessibility to medical care is much higher than in rural areas [17]. This gives patients in urban areas more choices when it comes to their care. They can go to medical institutions that specialize in their health conditions [18]. In contrast, in rural areas, health care providers are required to provide holistic and comprehensive care [19]. The absence of nearby health care facilities also makes it easier for physicians to provide continuity of care to a single patient [15]. Therefore, family physicians can provide continuous and comprehensive services in rural areas, two of the core values of primary care [15, 20, 21]. In contrast, for other specialists, rural areas may not be an ideal place to apply their expertise. They need to treat a narrower spectrum of diseases, which is rare in rural areas, and thus need to cover a wider geographic area with a larger population to stay in business [22]. As a result, the distribution of other specialists tends to shift to urban areas [23].
In Japan however, the distribution of family physicians shifted to the rural areas. This can be linked to the immaturity of family medicine in Japan’s healthcare system. In Japan only about 10 years have passed since family medicine was established as a clinical discipline with a board-certification system. Only 0.2% of all physicians in Japan are board-certified family physicians. Urban primary care providers were other specialists originally employed by a hospital, who then opened their own private clinics [5]. These former specialists treat some patients within their specialty, and also offer primary care services without being trained in primary care or certification as a family physician. Regardless of their ability to provide primary care, these “specialoids” are almost dominating the primary care labor market in urban areas, and patients are now accustomed to consulting specialoids as needed [5]. It is difficult, if not impossible, for family physicians, all of whom were board-certified recently, to enter this specialoid-saturated market. Therefore, they might prefer to work in rural areas where competition with these specialoids is less fierce. In a society like Japan’s, with immature family medicine, family physicians are at a disadvantage in the health professional market.
Japan’s unique system of health economics may also have affected the distribution of family physicians. Almost all Japan's clinics are private solo practices. Physicians are generally employed by a hospital as a domain-specific specialist in their early careers. After middle age, some of them set up their own clinics investing an average of US$880,000 [24]. It was extremely difficult for younger family physicians, to afford such an investment. Therefore, to continue practicing family medicine at a primary care facility, a substantial proportion of them may be employed by a public clinic set up by the local government to provide medical care in Japan’s rural, remote and underserved areas. These are a small fraction of all clinics in Japan.
The simulation analysis showed that the geographic maldistribution of physicians in Japan improved with a larger number of family physicians. The geographic maldistribution of physicians has been a serious social problem in Japan [25]. To compensate for the shortage of doctors in rural areas, public medical institutions in the rural areas were established by the national and municipal governments. Jichi Medical University, established solely for the purpose of training rural physicians, was established in 1972, and a regional quota, a special admission quota for producing rural physicians, was spread among most of the medical schools in Japan for the last ten years [26, 27]. Even with these ambitious national policies, the maldistribution of physicians has not changed. Instead, there is an even greater disparity in the supply of physicians between rural and urban areas [25, 28, 29]. The unique distribution of family physicians in Japan could contribute to ameliorating the maldistribution of physicians. Based on the results of this study, policies to increase the number of family physicians and general practitioners and reining in the number of other specialists is a plausible solution for national and local governments [30].
This study has several limitations. First, we could not obtain the data on all JPCA-certified family physicians because individual information of some of them was not available on the JPCA website. We considered, however, that selection bias for Japanese family physicians was minimal given the high (78.4%) covering proportion. Second, the simulation analysis assumed the distribution of family physicians did not change when it actually increased dramatically. If the number of family physicians increased to such an extent, it is possible that their geographic distribution substantially changed, meaning that, family physicians can replace specialoids in urban areas. In this case, the distribution of the total physicians would be different from that shown by the simulation. Above all it was not realistic that the number of family physicians in Japan increased by 72 times in a short period. The simulation was a thought experiment under an extreme assumption that showed, in a simple manner, the magnitude of the effect of the policy to increase the number of family physicians. Finally, the healthcare systems of Japan and the U.S. are so different, especially in terms of their medical insurance systems. The results of the comparison between the two countries should be interpreted cautiously.