Based the report of the Organisation for Economic Co-operation and Development (OECD) and European Union (EU) (6), the following countries were identified as countries without GP-gatekeeping (Table 1).

A narrative, rather than a systematic, review was chosen to give an overview, and cover a wide range of issues within the topic at the same time. Although narrative reviews often do not reveal explicit information about the literature search and why studies were found to be relevant (11), the authors of this article decided to include this information to increase transparency.

A PubMed and Cochrane search was performed. In PubMed, Medical Subject Headings (MeSH) were used to identify relevant literature regarding the role of GPs in health care systems without gatekeeping. Since the MeSH-terms care continuity and patient-centered care were indexed under comprehensive health care, the third and fourth search showed fewer results. The second to fourth search did not yield any additional relevant articles that had not been included before. In Cochrane, an advanced search was performed. The filter was set to “all text” and the same headings as in PubMed were used (Table 2). All full-text articles in English and German that met the topic were included. No filter regarding the publication date was applied.

The GP's self-perceived responsibilities and aspirations regarding family medicine core values and core tasks do not seem to depend on the health care system he or she practices in. Sturm described continuity of care while using the knowledge about the patient's social situation as essential and called for ongoing responsibility during and after the consultation and while receiving secondary care, although German GPs do not generally function as gatekeepers (25). In Israel, patients may consult any GP or specialist within their health care plan, although the country has tried to move toward a gatekeeping system (26, 27). Nonetheless, the study of Tabenkin et al. showed that almost all participating GPs considered “coordination of all patient care” as very important, a third-rated “24 h responsibility for patients” as important (15). But the traditional role of the GP as the first contact person within the health care system may shift from the individual to the practice, where the GP leads a team that collectively takes responsibility and provides a patient-centered medical home (28).

Several studies demonstrated that GPs prefer the gatekeeper role (24, 29–31) due to multiple reasons, e.g., GPs in Iceland thought that mandatory referral increased the flow of information and enhanced the communication with a specialist (32). Fewer hospital admissions, better quality of care, and lower health care cost were also mentioned (24). Rosemann et al. showed that not only the patient had a better experience with a referral, but also the GP if he or she was the initiator of the referral (30). But there are also critical voices among primary-care scientists (12). Greenfield et al. called for a revision of gatekeeping regulations in the United Kingdom, where GP-gatekeepers are established, to grant patients more choices and by that “facilitate more collaborative work” with other specialties (23). A Lithuanian study suggested a flexible gatekeeping model regarding adolescents' reproductive health care, as GPs questioned the appropriateness of gatekeeping in this field due to a lack of willingness to provide these services, insufficient training, and inadequately equipped surgeries (33). GPs considered formal specialty training as essential (15).

The GP's choice of specialists may depend on the health care system, as they are sometimes required to refer patients within a network (34).

A large study that included 17,391 patients in 10 different countries (with and without gatekeeping) evaluated the patient's view on general practice and found no large discrepancies in regards to aspects of care. Minor differences were the relatively positive evaluations given to preventive services in the United Kingdom and the GP's availability (either by an appointment or by phone) in Switzerland, Germany, and Belgium. The relatively negative evaluations were given for service in case of emergencies in the United Kingdom and Slovenia. Slovenian patients also gave relatively negative evaluations regarding the GP's interest in their personal situation. A tendency toward a more positive overall assessment was seen in Switzerland, Germany, and Belgium (countries with no GP-gatekeeping). For the United Kingdom and the Scandinavian countries, a trend toward a less positive assessment was found (22).

In Germany, multiple attempts have been made to shift to a more family medicine-centered care model. Although it has only been established in voluntary projects, Himmel et al. showed that the majority of over 400 participants from the general population would accept their GP as gatekeeper and appreciated the coordination of secondary care by the GP. Nearly two-thirds wanted to consult their GP during hospitalization. Participants who had a GP at the time of the survey were more likely to accept him or her as gatekeeper compared with participants without a GP (35). The results are in line with a study from the United States (17). Another study from Israel reported numbers that were less clear, but trending toward the same direction: a third of all respondents preferred self-referral to a specialist, 40% preferred their GP to act as a gatekeeper, and 19% preferred the GP to coordinate care but to refer themselves to a specialist (13, 15). A few years before, 52% of the respondents were in favor of direct access to specialists, but the rate was lower in patients who were older than 45 years and patients whose primary-care physician was a specialist in family medicine (16). The denial of a referral resulted in lower satisfaction rates (20). On the contrary, a patient's experience was more positive if the initiative for a referral came from the GP. The authors concluded that this supports the GP's role as gatekeeper, since, in Germany, the patients could have directly scheduled an appointment with a specialist (30). However, satisfaction rates were not compared to patients who had opted to do so.

Although gatekeeping is often focused on when accessing the patient's perspective on the GP role, van den Brink-Muinen et al. demonstrated that the doctor-patient communication was hardly influenced by it. They compared data from countries with and without gatekeeping and only found that paraphrases, checks for understanding, and requests for clarification and opinion were found more often in consultations of the gatekeeping countries (36). Two newer reviews conclude that evidence regarding the effect of gatekeeping on quality of care and patient or provider satisfaction is inconsistent and limited (18, 19). A large international study using survey data from over 25,000 patients in 17 countries showed that patients were highly satisfied with their GPs, independent of health care system characteristics such as GP density, fee for service reimbursement, gatekeeping, or the GP's role as first contact (37).

Among a U.S. group of nearly 1,500 specialists (cardiology, endocrinology, gastroenterology, general surgery, neurology, ophthalmology, and orthopedics), the attitudes toward primary-care gatekeepers were mixed. Compared with non-salaried physicians, salaried physicians were more in favor of gatekeepers, as did physicians with a greater percentage of practice income derived from capitation (21). A study from The Netherlands showed that specialists were particularly interested in collaborating with GPs due to their function as gatekeepers. However, an informal network with incidental contacts fulfilled the collaborative needs of the specialists. They did not regard GPs as equal and felt that GPs could learn a lot from them, but that there was nothing to learn vice versa (38). Specialists were satisfied with the appropriateness and timing of the referral but would have appreciated more information about the patient's medical history or medications (30). If multiple specialties or even professions address the same medical problem, it is likely that more than one will claim the gatekeeper role. A study among ophthalmologists, GPs, orthoptists, optometrists, and opticians regarding common eye problems was at least able to show a trend toward a medical (ophthalmologist, GP) rather than a non-medical gatekeeper (optometrist) (31).

Compared with the other three groups, the policy maker's perspective regarding the GP's role in complex medical systems is less well-researched. Mariñoso and Jelovac used a statistical model to identify optimal contracts that would induce the best behavior from a public insurer's point of view and found that gatekeeping was superior wherever GP's incentives matter (39). Philips et al. performed a multivariate logistic regression analysis using secondary data showing that gatekeeper requirements are associated with higher utilization of widely recommended cancer screening interventions (e.g., mammography). No association was found regarding the use of less uniformly recommended interventions [e.g. prostate-specific antigen (PSA) checks]. The authors concluded that “policymakers should consider the potential benefits of gatekeeper requirements with respect to preventive care when designing health plans and legislation” (40).

Only two studies from Israel reported data directly displaying the policymaker's perspective (14, 15). The members of the Ministry of Health, the Sick Funds' central administrations, and the Israel Medical Association (IMA) central office were interviewed and stated that the highly trained GP should play a central role in the health care system. GPs should be highly accessible coordinators, able to weigh cost considerations. However, only about half of the participants supported a GP-gatekeeper model. The perceived barriers to implement such a model included loss of faith in GPs by the general population, dearth of GPs with adequate training, low stature, lack of 24 h-availability, resistance from specialists, and competition between the sick funds.

As this is a narrative review, the typical limitations apply: compared to a systematic review, the literature search was more subjective and less structured. The aim was to give an overview of the GP's role in a complex medical system without gatekeeping. It is possible that a more systematic research and the use of other/further MeSH terms would have identified more articles, although relevant literature was added while reviewing the initial list. The aim of the review is to describe the GP's role in health care systems that are similar to each other (no GP-gatekeeping) without focusing on a national perspective. All authors have worked and lived in other countries. However, it is possible that the article was influenced by their experience in Germany. Despite the fact that the debate of the GP's role is ongoing, most articles are over 10 years old.