This study explored the experiences and perceptions of APPs and GPs towards both the implementation and deployment of APP within Dutch primary care and found that it is difficult for APPs to carve out a place for themselves within the healthcare landscape.
Within the present study, four themes emerged from the data through which APPs and GPs’ experiences of APP deployment and implementation can be understood. The first theme sheds lights on the fact that the success of APP depends on both the trust of the GP and whether they perceive it as having clear added value in comparison to the usual care. The second theme underscores that the support of GPs is essential for APPs, as far as it helps to, amongst other things, get different referral flows going. The GP also plays an important role in terms of building the self-confidence of APPs, in creating uniformity within patient care, and in terms of helping to bring about a team that works under one roof. The lack of funding for APP raises concerns over the deployment of APP among APPs, GPs, and physiotherapists. The third theme points towards the fact that the position of APPs needs strengthening. Indeed, the professional profile of APP is something that proved to be unclear to both GPs and APPs themselves. In the absence of a uniformed way of working, everyone is still searching, which, in turn, results in diversification. GPs’ reluctance to hand over control also profoundly impacts on the role of APPs. Amongst APPs, there is a need for better positioning, support, and profiling from the professional association as well as for training which includes more depth and practical education. The fourth theme pertains to both the tension that persists around ownership of patients with musculoskeletal complaints and the competition between APPs and physiotherapists. This is compounded by a lack of adequate funding and the ability to generate patient flow for the physical therapy practice to which APPs are affiliated. Moreover, the APP model seems to insufficiently adhere to GPs’ core values.
Comparison with literature
Many of the themes identified are in accordance with earlier publications on APP, such as the role of trust and need for acceptance by doctors [14, 16], recognition of the added value by doctors [14, 16, 17] and the establishment of an appropriate financing structure [14, 17]. The present study shows that many of these previously identified factors, such as physician trust and demonstrating clear added value to stakeholders and the financing structure, have hitherto not been sufficiently realised to facilitate the implementation of APP within Dutch healthcare. The most important barrier, however, appears to be GPs’ reluctance to hand over authority and control. This appears to stem from specific characteristics of Dutch general practice, such as long-term doctor-patient relationships and GPs’ strongly held core values, but also derives from the traditional authority that GPs have over physiotherapists as a result of differences in educational level, which persists because of the lack of sufficient training and entrusted professional activities.
Introduction and support from within the organization have been described as helpful in studies of APP embedded in secondary or tertiary care [14, 15, 17, 18]. Such support is lacking in the implementation of APP in the Netherlands, and individual APPs working independently in primary care must build a partnership without any support.
A number of studies have shown that the availability of training at an appropriate level is critically important [14,15,16]. Our study shows that, according to the experiences of the APPs, both the form and scope of the current education is not in line with the demands of the professional field and, moreover, is not sufficiently different from their prior training and thus lacks added value for them. In addition, individual APPs are currently responsible for organising their own practical training in the field. It is unclear to what extent this is feasible for APPs given the limited scale of most of their collaborations, where guidance often has to be provided by an individual GP, while gaining practical experience is dependent on the limited number of patients registered with this GP.
Furthermore, a number of studies have shown that a clear delineation of the role of APPs and greater standardisation of working procedures is important [19, 20, 22]. A recent qualitative study examining the goals, roles and tasks of APPs in the Netherlands revealed that the participants found it difficult to state clear goals for APPs and that there is no consensus concerning the positioning of APPs . A study on how best to shape the interprofessional collaboration between GPs and established healthcare professionals  showed that these collaborations do not always go well and that it is crucial to establish a shared vision and clarity over work structure, procedure, and role distribution. Awareness of each other's context and expectations was also found to play a key role. According to the APPs and GPs who took part in this study, a clearly defined role and standardisation of process and working methods of APPs has yet to be realised. This makes it incredibly difficult to develop the partnership between APPs and GPs.
Amongst GPs, there is a need to improve the already existing collaboration with physiotherapists to ensure the increasingly complex care of patients with musculoskeletal complaints . Within current Dutch primary care, around half of all GPs already have an existing collaboration with a physiotherapist , while a large proportion of patients with musculoskeletal complaints visit a physiotherapist via Direct Access Physiotherapy . In this context, the question is whether there is a need therefore for a new type of care provider, such as APPs, or whether there is a need to revise the existing collaborations with physiotherapists, by improving the level of communication and having one-off diagnostic consultations.
In other countries, such as Australia and the United Kingdom, APP has emerged in response to urgent demand from physicians [14, 16]. Here, involved stakeholders have felt sufficient urgency to change and, moreover, physicians have endorsed the need for the use of APPs [14,15,16]. Within the present study, there was no such urgency and need expressed by GPs. This might relate to differences in the organisation of healthcare systems, not to mention the good accessibility and continuity of Dutch GP care. It has also been found that when APP is not initiated by physicians themselves, then its implementation is altogether more difficult and dependent on goodwill . This also appears to be the case with the implementation of APP in the Netherlands.
It remains to be seen to what extent APP fits within the Dutch College of General Practitioners future vision  in which the GP, as the first point of contact, maintains an overview of medical care and determines, together with the patient, what care is necessary and appropriate. The Dutch General Practitioners Association has recommended that, when entering a partnership with a new care provider, GPs must determine, before doing so, to what extent the core values and core tasks are to be guaranteed [27,28,29]. Moreover, GPs are advised to assess if the collaboration with this new care provider corresponds to their own preferences, ambitions, and vision of GP care [27,28,29]. In addition, a study amongst patients of Dutch GPs showed that patients’ wishes regarding healthcare providers should be considered in ever-increasing collaborations with the GP practice . At present, it is not feasible for APPs to adequately align with the key conditions that GPs want to see fulfilled before they are willing to change their practices, while it remains unclear to what extent patients' wishes are being heeded in the implementation and deployment of APP.
The importance of connecting to core values was also highlighted in a study evaluating barriers to the implementation of the Dutch General Practitioners Association treatment standards . This study demonstrated that, despite the positive attitude of GPs towards the implementation of these standards, GPs only follow the standards when they are in line with the core value of patient-centred care. This makes it clear that, even with an improved positioning of APP, connecting to the core value of person-centred care is decisive in successfully implementing APP. There seems to be a lack of vision regarding under what conditions this can be met, which, in turn, makes it difficult for individual APPs to connect with GPs.
Strengths and limitations
One of the strengths of this study is its credibility . The starting point was an extensive literature review, which subsequently formed the basis of the interview guide. Multiple researchers collaborated on this study, and during the analysis, two researchers coded independently of each other, and subsequently the codes and themes were extensively coordinated and discussed within the research team. In addition, the full scope of the use and implementation of APP was examined by using concepts from the constellation approach as sensitising concepts in developing the interview guide. Moreover, all the participants were sent a member check after the interview and their responses were included in the analysis. Another strength concerns the conformability  of the results, as a large team from different backgrounds worked on the study. Moreover, a good audit trial was carried out, during which the selection process around the analysis was recorded and explicit attention was paid to the views and thought processes of each individual team member. This was an important aspect as one individual researcher (SP) is a physiotherapist and was involved in conducting an observational pilot study that evaluated the APP model of care and, as such, was more familiar with the perspective of APPs. The presence of possible disconfirmatory cases was discussed within the research team, but although there was diversification amongst the participants, no disconfirmatory cases were identified. The findings were in line with other studies examining the implementation of APP models of care. The transferability  of the findings is unclear. Despite there being similar findings in extant literature on implementation level, comparison with international literature is difficult given the specific Dutch context. Although we used maximum variation sampling, we were compelled to recruit GPs through convenience sampling given the limited number of GPs who were willing to participate, which meant that we failed to include GPs who were not open to implementing the APP model. This probably hinders the transferability of our findings, as far as we may have missed aspects of the GP perspective. However, gaining trust in APP, the need for a clear added value, reluctance to hand over control, and strongly held core values was expressed by all the participating GPs. There may also be shortcomings in the dependability  of the findings. Although we collected data until no new themes derived and flexible analysis took place, data collection and data analysis were not a wholly iterative process. In addition, there is a possibility that some of the participants may have felt less free to express themselves during the interview, out of concern that they may have, despite being anonymised, been recognised by colleagues and stakeholders based on their specific characteristics.