The landscape of Professional Doctorate provision in English Higher Education Institutions: inconsistencies, tensions and unsustainability

This article reports findings from a recent research project, commissioned by the Higher Education Funding Council for England (HEFCE), which explored the current landscape of professional doctorate (PD) provision in English Higher Educational Institutions (HEIs) (Mellors-Bourne et al., 2016). Given the absence of a clear definition by the Quality Assurance Agency in England, of the characteristics which distinguish PDs from practice-based doctorates and the Doctor of Philosophy, this paper makes a timely contribution through considering the inherent characteristics of PD programmes. The paper presents an overview of the state of play of PD programmes currently available in HEIs in England, highlighting how the proliferation of PD titles and programmes, and inconsistencies between the various programmes, has resulted in confusion around what PDs are, the contribution they make, and the value they add to professional practice. Consideration is given to the tensions created through the expansion in the number and types of PDs available and the implications of these tensions with regard to the future sustainability of PD programmes in general and, in particular, in relation to the Professional Doctorate in Education (EdD).


Introduction
This article reports findings from a recent research project, commissioned by the Higher Education Funding Council for England (HEFCE), which explored the current landscape of professional doctorate (PD) provision in English higher education institutions (HEIs) (Mellors-Bourne et al., 2016). The research entailed an extensive review of PD provision in England, updating, and adding to, findings from previous studies, for example, the commissioned research on PDs of the United Kingdom Council for Graduate Education (UKCGE) published in 2011 (Fell et al., 2011). Given the absence of a clear definition by the Quality Assurance Agency (QAA) for England of the characteristics that distinguish PDs from practice-based doctorates and the doctor of philosophy (PhD) (QAA, 2015), this paper makes a timely contribution to the existing knowledge base on PDs. It presents an overview of the state of play in terms of PDs currently available in HEIs in England, giving particular consideration to the inherent characteristics of these programmes. The paper also explores the tensions created through the expansion in the number and types of PD programmes available, and the implications of these tensions with regard to the future sustainability of PD programmes in general and, in particular, in relation to the professional doctorate in education (EdD).

Aims of the paper
The HEFCE-commissioned research, from which this paper emerges, was conducted by the Careers Research Advisory Centre (CRAC) and the University of Brighton in 2015. The broad aims of the research were to examine existing PD provision and understand the models used in programme delivery within English HEIs. The research also considered HEIs' strategies for future PD provision, and explored the skills and attributes that PD programmes seek to develop, and the impact they have on PD graduates and other stakeholders. Drawing on findings from the research, this paper focuses on the following three aims: • to provide an overview of the extent and range of PD provision in English HEIs • to identify distinct characteristics pertaining to such provision, giving consideration to the skills and attributes that PD programmes develop in candidates • to consider the future sustainability of PD programmes generally, and specifically in relation to the EdD.

The development of professional doctorates
Since the early 1990s there has been a huge increase in the range and nature of PDs in Australia, New Zealand and the United Kingdom (UK), although the growth in PD provision has been relatively slow in Europe and in America (NQAI, 2006). The expansion in the number of PDs offered by English HEIs is evidenced by findings from various studies conducted over a number of years. For example, Bourner et al. (2001) found that, in 1998, 109 PD programmes were offered in 19 subject areas within UK HEIs, with the majority being offered in five areasbusiness administration, education, engineering, medicine and psychology. By 2009, the number of PD programmes offered was reported to have increased to at least 308 (Brown and Cooke, 2010: 9), and by 2015, approximately 320 PD programmes were identified as being offered in various subject areas within English HEIs (Mellors-Bourne et al., 2016). As noted by Klenowski et al. (2011: 681), PDs were designed for 'professionals to research real-world problems and issues relevant to their particular profession, industry and/or community'. PD programmes are seen as providing a potentially more appropriate, credible route to doctoral status than other types of doctorates for those working and seeking development in their professional practice (Pratt et al., 2015). They are also often specific to particular professional contexts, with a variety of different PDs having been developed to accommodate various niche markets (Armsby, 2012: 135). Burton and Kirshbaum (2013) note that due to potential economic gains, there are increased initiatives to recruit overseas students on to PD programmes and, to this end, some PD programmes are now delivered entirely online. Thus, the overall expansion in PD provision can be seen to reflect the needs of different professionals and a progressively diverse student population. It is also a response to marketing strategies used by HEIs, as well as to demands from industry, professional bodies and professionals themselves for more relevant forms of learning, skills and qualifications (Rolfe and Davies, 2009).

Defining professional doctorates
It is commonly acknowledged that all doctorates make an original contribution to knowledge. According to the QAA (2011: 7), UK doctorate qualifications are required to make a contribution to existing knowledge in their discipline or field, through original research or the original application of existing knowledge to understanding. Although there are some variations in terms of the definitions used to describe PDs, they all tend to include reference to the contribution made to professional practice. However, Kemp (2004: 404) makes the point that we need to 'dispense with the flawed notion that … the professional doctorate contributes principally to practice', and asserts that PDs, as other forms of doctorates, also make theoretical and methodological contributions. One of the most well-known and frequently used definitions of PDs is that provided by the United Kingdom Council for Graduate Education (UKCGE) in 2002, which defined the PD as: A programme of advanced study and research which, whilst satisfying university criteria for the award of a doctorate, is designed to meet the specific needs of a professional group external to the university, and which develops the capability of individuals to work within a professional context (UKCGE, 2002: 62). There are, however, overlaps in the definitions attributed to PDs, practice-based doctorates and, in some cases, work-based doctorates. For example, in 2007, the European University Association stated: '"Professional doctorates", or practice related doctorates, are doctorates that focus on embedding research in a reflective manner into another professional practice' (EUA, 2007: 14). Similarly, in 2011, the QAA stated: 'In professional and practice-based doctorates the research may be undertaken in the workplace and may have a direct effect on improving the professional practice of individuals in their host organisation' (QAA, 2011: 7). The QAA guidance also stated that UK PDs: are designed to meet the needs of the various professions in which they are rooted … successful completion of the degree normally leads to professional and/or organisational change that is often direct rather than achieved through the implementation of subsequent research findings (QAA, 2015: 9).
For the purpose of this paper, the 2002 UKCGE definition, as stated earlier, will be used as a basis for defining PDs, with the addition of two further points: • PD programmes also meet the needs of professional groups within the university, as well as those external to the university • PD programmes include only those programmes with 'professional doctorate' in their title or description, where these do not lead to any other type of award.
Thus, in the context of this paper, a PD will be defined as: A programme of advanced study and research that satisfies university criteria for the award of a doctorate, which develops the capability of individuals to work within their professional context through meeting the specific needs of professional groups internal or external to the university, and which has 'professional doctorate' in its title or description, and does not lead to any other type of award.

Methodology
A key objective of the HEFCE-commissioned research was to seek stakeholders' perspectives about various aspects of PD programmes and provision. The research design involved three broad strands: • Desk-based research, including a literature review of articles and reports relating to theoretical and empirical studies focusing on UK-based PDs. To help identify the number and range of PD programmes available in English HEIs, information was also collected from HEI websites, and from the Higher Education Statistics Agency (HESA). • An online survey administered to 120 English HEIs, including all HEIs with research degree awarding powers. The survey focused on ascertaining the number and types of PD programmes offered, and institutions' future strategies for PD provision. This data was drawn from the 63 institutional responses to the survey, and supplemented with additional data collected through the desk-based research. • In-depth qualitative interviews with 30 stakeholders from a purposeful sample of 14 English HEIs, covering 22 different PD programmes. The 14 institutions represented a range of established PD disciplines, as well as some emerging new disciplines. The sample, which comprised four pre-1992 institutions, eight post-1992 institutions and two disciplinary specialists, included institutions in the process of closing down some of their PD provision, as well as others planning to start up new PD programmes. The stakeholders interviewed included senior academics and administrators in HEIs providing PD programmes, PD programme leaders, PD students and alumni, and employers with PD students or alumni working for them.

Findings
Findings will be considered within two main sections. Quantitative findings relating to the extent and range of PD provisions in English HEIs are reported in the first section; findings of a more qualitative nature relating to the characteristics pertaining to professional doctorate programmes are reported in the second section.

The number of professional doctorate programmes and awards offered
Taking into consideration pre-1992, post-1992 and disciplinary specialist institutions, 123 English HEIs were recorded. Findings suggest that 86 of these HEIs offered PD programmes and, between them, these institutions offered 320 different PD programmes. Specifically, these programmes were provided by 37 pre-1992 institutions, 41 post-1992 institutions, and eight disciplinary specialist units; thus, the average number of programmes per institutions was just under four, and this was broadly similar for both pre-1992 and post-1992 institutions (Mellors-Bourne et al., 2016: 21-2). It is important to note that ascertaining the precise number of PD programmes available in English HEIs was not a straightforward exercise due to the different ways in which HEIs counted the number of programmes offered, and discrepancies in what constitutes a PD. For example, some HEIs counted full-time and part-time versions of the same programme as separate programmes, while others listed separately programmes with a range of delivery patterns and, in some cases, co-delivery partners, and counted these as one single programme. To avoid double-counting, these variants were excluded when calculating the total number of programmes available; similarly, where an HEI ran a generic PD programme that attracted candidates from different specialist areas, this was counted as one programme. However, where a single PD programme offered different specialist pathways and different awards, the number of programmes counted reflected the number of different awards offered (ibid.: 21). A decision was made not to count PDs in engineering (EngD) on the grounds that the EngD is considered to be part of industrial training provision, its delivery tends to be based in an industrial partner, and it results in a PhD award (ibid.: 14). The doctorate in clinical psychology (DClinPsyc), which is also seen as preparation for registration as a clinical psychologist, however, was counted as a PD as its structure is similar to that of other PDs (ibid.: 14), and it leads to a PD award.
Data relating to the number of programmes available implies that there has been only a small increase in the number of PDs between 2009, when Brown and Cooke (2010: 9) estimated there to be 308 different PD programmes, and 2015 when Mellors-Bourne et al. (2016) estimated there were 320 different PD programmes. There is, however, no clear record of the criteria used by Brown and Cooke when calculating the number of programmes available; a direct comparison between findings from these different studies is, therefore, not possible.

Subject areas in which professional doctorate programmes and awards are offered
It was possible to classify the 320 PD programmes and awards available in English HEIs into ten broad subject areas as follows (see Mellors-Bourne et al., 2016: 25): • heath and social care (81 programmes provided by 37 HEIs) • education (72 programmes provided by 54 HEIs) • psychology and psychotherapy (58 programmes provided by 35 HEIs) • business and management (48 programmes provided by 38 HEIs) • other science and technology (14 programmes provided by 13 HEIs) • medicine and dentistry (13 programmes provided by 10 HEIs) • social sciences and law (12 programmes provided by 10 HEIs) • humanities (including theology) (12 programmes provided by 10 HEIs) • creative and performing arts (seven programmes provided by six HEIs) • generic (three programmes provided by two HEIs).
It is evident from the above list that there are four specific areas in which PD programmes are particularly prolific, namely: health and social care; education; psychology and psychotherapy; and business and management. In each of these areas, the number of institutions offering programmes is significantly fewer than the number of programmes available (for example, 72 education PDs offered by 54 HEIs), thus implying that where programmes are offered in any one of the areas, there is a tendency for HEIs to offer multiple programmes. With regard to other subject areas, the number of programmes available largely reflects the number of institutions offering the programme, implying that HEIs offer only single programmes in these areas.
The age of PD programmes in English HEIs ranged from 0 to 25 years, and a direct correlation was found between the age of the programmes and how prolific they are. For example, all programmes over 15 years were in the areas of health and social care, education, and psychology and psychotherapy (Mellors-Bourne et al., 2016: 27-8). However, evidence indicates that over half of the PD programmes available have been launched within the last five years, and this is reflected in the increasing number of specialized PD programmes, both within the four main PD subject areas, and in subject areas where only a small number of programmes are available. For example, within the area of education, programmes relating to higher education management, educational psychology and educational leadership, as well as to specific school curriculum areas such as literacy, have recently been developed. Furthermore, new PD titles have emerged within subject areas that traditionally offered relatively few PD programmes, including, for example, in the areas of theology and criminology, and others are being planned in the areas of data science, social policy, applied linguistics, sport science, music and the creative arts, and design (ibid.: 26). Within some of these relatively new subject areas, several variations in the titles of similar programmes were noted with, for example, seven different award titles relating to the eight theology programmes identified.

Professional doctorate enrolments and completions
Although data relating to the number of enrolments and completions for all 320 PD programmes offered in English HEIs was not available, it was possible to gather data relating to enrolments and completions for a subsample of 100 programmes. These programmes largely reflect the overall range of subject areas, with 79 of the 100 programmes being in the areas of health and social care, education, psychology and psychotherapy, and business and management, and 21 within other, smaller subject areas.
Evidence relating to these 100 programmes for the 2013/14 academic year indicated that there were just under 2,600 students enrolled across the programmes, suggesting an average of 26 students per programme. However, as many programmes take between five and seven years to complete, this implies that many of the cohorts are small in size. It was also noted that the average number of students enrolled on these programmes differed significantly according to subject areas, with education, business management, and psychology and psychotherapy programmes attracting the largest number of students per cohort. Findings relating to the number of programmes and numbers of students enrolled on each programme are detailed below (see Mellors-Bourne et al., 2016: 28): • 899 students were enrolled on 25 education programmes, averaging 36 students per programme • 592 students were enrolled on 16 business and management programmes, averaging 37 students per programme • 485 students were enrolled on 16 psychology and psychotherapy programmes, averaging 30 students per programme • 337 students were enrolled on 22 health and social care programmes, averaging 15 students per programme • 287 students were enrolled on 21 'other' programmes, averaging 14 students per programme.
Further evidence indicates that within this sample of 100 programmes, in the 2013/14 academic year there were 524 new enrolments. Of these, there was an average of nine new enrolments per psychology and psychotherapy programme; eight per business and management programme; six per education programme; two per health and social care programme; and only two per 'other' subject areas (Mellors-Bourne et al., 2016: 29). One particularly worrying finding, however, is that there were no starters in 35 of the 100 programmes and, within the areas of education, business and management, and psychology and psychotherapy, no starters were reported in one in five programmes. Additionally, in the area of health and social care, there were no starters in over half the programmes, and there were no starters in up to three-quarters of the programmes relating to 'other' subjects.
In terms of completions, 290 completions were recorded for the 2013/14 academic year. These comprised 108 in psychology and psychotherapy, 103 in education, 31 in health and social care, 26 in business and management, and 22 in 'other' subject areas (ibid.: 30-1). The data also suggest that there have been increases across all subject areas in the number of completions since 2009. However, this could partially reflect the fact that more completions are likely as the programmes themselves mature.

Key characteristics of professional doctorate programmes
There were two main characteristics identified as pertaining specifically to PD programmes; these can broadly be classified as follows: • Key characteristic 1: The intended outcome of PDs is to make an original contribution to professional practice and/or policy through research. PDs are typically undertaken by professionals and practitioners working in a professional context; they provide opportunities for these groups to undertake research directly related to their professional practice, and to reflect critically upon this. PDs tend to be practitionerdriven: they focus on an aspect of professional practice that practitioners or professionals themselves want to explore (Costley and Lester, 2012;Costley, 2013), and thus have the potential to make a significant and direct impact on professional practice and/or policy. During interviews with senior members of staff in HEIs, the contribution made by PDs to candidates' professional practice was typically expressed in terms of 'the potential to make a difference within their own institutional settings'. A further common viewpoint related to the speed at which such changes in practice can be implemented, expressed by one senior member of staff as 'professional doctorates are advantageous as impact on their [PD candidates'] practice can be maximized and it is immediate'. When comparing the impact of the PD to that of a PhD, another senior member of staff commented: 'The programme has an impact on their [PD candidates'] organizations; this is the main difference between the PD and PhD'. • Key characteristic 2: PDs include structured (sometimes referred to as taught), supervised and cohort-based experiences, with emphasis on candidates acquiring research skills that can be used within their professional practice. PD programmes commonly comprise two stages. Stage 1 usually lasts between 18 months and two years, and involves input on 'research training, assessment and cohort-based learning'; while Stage 2 typically involves 'independent research, a thesis and examination with viva' (Mellors-Bourne et al., 2016: 16). This two-stage structure reflects the structure of PDs identified by Park (2007), as well as the model of PDs described by the QAA: Professional and practice-based doctorates normally include structured elements such as lectures, seminars, and workshops on both discipline-specific and researchspecific content, with an emphasis on the candidate acquiring skills relevant to their professional practice, in addition to producing original research (QAA, 2011: 15).
Although there are strong commonalities across Stage 2 of different PD programmes, with this forming the thesis stage in all cases, there are differences in the required length of the thesis. Most are around 50,000 words, but there are variations from a 25,000-word thesis with a portfolio and other work, to an 80,000-word thesis. It was also common for progression to Stage 2 to be possible only on the successful completion of Stage 1 and, regardless of the thesis length or length of time spent in Stage 1 or 2, a doctoral thesis is required to comply with the QAA's requirements of 540 credits, with a minimum of 360 credits at Level 8 (doctoral level) (QAA, 2015: 17). For PD programmes that are credit-based in Stage 1, a common model was to require 180 Level 7 (master's level) credits at Stage 1, and 360 Level 8 (doctoral level) credits at Stage 2, although some PD programmes also required Level 8 credits during Stage 1. Credits at Stage 1 were typically awarded following the successful completion of between one and nine marked assignments, portfolios or presentations. There were, however, numerous variations within Stage 1 of PDs in terms of the ways they were organized, the assignments and/or modules students were required to undertake, and the level students were expected to reach before progressing to Stage 2.
Although not unique to PD programmes, a further characteristic of PD programmes was that all candidates were assigned at least one supervisor. While most PD candidates were allocated one supervisor, a significant number were allocated two, and occasionally candidates had three supervisors. In a small number of cases, one of these supervisors was employment-based and, in some cases, where candidates were studying on distance-learning PD programmes, they worked entirely with remote supervisors. In the case of distance learning and the allocation of remote supervisors, supervision was typically conducted online during the early stages of the PD, and more commonly conducted via telephone and Skype during the thesis component. However, in most cases, measures such as online discussion groups, in which all students were expected to participate, were put in place from Stage 1 of the PD to support the development of working relationships with supervisors, and with other PD students within their cohort. PD candidates commented that working with remote supervisors proved more challenging than working faceto-face with supervisors (Mellors-Bourne et al., 2016: 19). For example, they reported feeling reluctant about contacting supervisors when they lacked confidence or understanding about what was expected of them in terms of contributions to online discussions and assignment requirements, and when they wanted advice on how to progress with their work. Concerns relating to this reluctance were summed up by one PD candidate as follows: It's scary contacting a supervisor when you don't really know them, they might see you as academically inadequate and incapable of working at this level; you don't really want to show them any weaknesses, so it's easier not to contact them, but then that leads to problems as well, as then you wouldn't get any support. Nasiri and Mafakheri (2015: 1,964) also found that where doctoral students are supervised at a distance they are likely to lack good personal knowledge of each other, thus leading to supervisory conversations being of a formal nature, rather than being an informal environment for discussion. More fruitful and trusting working relationships tended to develop between distance PD candidates and their supervisors when frequent and regular contact was established, especially where this was via Skype or other visual means.

Knowledge, skills and attributes developed by PD programmes
One common and key characteristic that PD programmes develop in candidates is an increased level of criticality, particularly in relation to their professional practice (Burgess et al., 2013). Interviews with PD candidates reflected this finding, with candidates reporting that undertaking a PD prompted them 'to think more critically about my [their] work', and to 'look behind what is going on in practice … rather than accepting things at face value'. Similarly, PD supervisors commented that in undertaking a PD, candidates 'gain a wide range of skills to challenge their thinking about professional practice', and 'they start to interrogate their own professional understandings. … They start to stand back and understand things differently, from angles they had never previously thought of'.
Developing increased levels of criticality, however, led to ambiguity in terms of candidates' continued acceptance of some workplace practices. For example, the research reported that candidates found that their heightened criticality led to them 'having to unlearn things you took for granted, including commonly accepted workplace practices'. Similarly, Burgess et al. (2011) noted that as criticality rises, candidates may find it a delicate balance between being critical, while also maintaining good relationships in the workplace, and Seddon (2001) reported that PD candidates had difficulty in grappling with their developing skills as a researcher and their researcher identity, while maintaining their professional identity.
PD candidates and alumni also reported increased self-awareness, a more reflective approach to their professional practice (Fenge, 2010) and increased self-confidence within their professional settings (Smith, 2013). Likewise, Butcher and Sieminski (2006) found that, in their survey of EdD alumni, the EdD programme was reported to have helped candidates reflect on and revise their professional practice. In particular, when reflecting on practice, EdD students made links between theory and practice, and this resulted in an increased confidence to apply their new knowledge to their working practices. Findings from interviews with PD candidates and alumni revealed that the structured modules that formed part of their PD study, and work they undertook as part of their literature review, helped them to gain greater 'academic understanding of their field and greater engagement with theory' (Mellors-Bourne et al., 2016: 53).
Other knowledge, skills and attributes that candidates and alumni reported they had developed include: research methods and analytical techniques; reading, writing and presentational skills; a more critical, reflective and analytical approach within their professional practice; an appreciation of alternative perspectives; improved construction of an argument; and increased confidence and credibility in their professional role (ibid.: 54-6). Expanding on this list of skills and attributes, PD programme leaders commented that during PD study, candidates 'learn to design and manage a major inquiry type project and wrestle with deeply complex issues in their workplace'; they also 'learn how to make links between academic theory and practice', and 'although this takes time, they grapple with understanding arguments and concepts in the literature, and from this they begin to figure out how the literature plays into their understanding of the particular context of their project'.
When asked what supported candidates' learning during their PD study, reading and structured PD sessions were high on the list; however, one of the most noteworthy ways in which candidates considered learning took place was through discussions within cohort groups. Cohort approaches are considered to enable group work and the sharing of ideas (Wisker et al., 2007: 309), to reduce social isolation and anxiety (Bentley et al., 2004), and to empower student learning by developing higher cognitive processes through interaction (Leshem, 2007). Additionally, as asserted by Wellington and Sikes (2006: 732), PD candidates put high value on the collegiality, support, friendship and social interaction that cohorts offer, and they appreciate opportunities to meet people from different and similar backgrounds, and opportunities to be introduced to and share new and different ideas. PD candidates reported that face-to-face meetings with others in their cohort was one of the most enjoyable, supportive and valuable aspects of the PD experience, a 'space where so much of the learning takes place', and where 'everyone in the cohort knows what you are going through, the group offers the support you need to keep going when it all seems too difficult'. Candidates and supervisors also reported that where PD programmes included cohorts of students from a diverse range of professional and cultural backgrounds, this was particularly advantageous in terms of challenging assumptions held by individuals. In the case of online discussion forums as a component of online PD programmes, where measures had been taken to support candidates to get to know and feel confident about contributing to discussions, these were also valued by students for the learning that took place. Senior HEI staff echoed this view, with one senior member of staff stating: 'Significant collaboration occurs between students engaged in the online PD programme … with the online dimension facilitating a community of practitioner researchers from a wide range of countries around the world'.
The paper has so far focused on the growth in numbers and types of PD programmes available in English HEIs, and on the value PDs offer in terms of the knowledge, skills and attributes they develop in candidates, and the original contribution they make to professional practice and policy. In the discussion that follows, attention will be given to the implications of the increasing numbers and variations of PD programmes. To exemplify these implications, consideration is given to one particular type of PD programme -the professional EdD.

Discussion
The growing number and types of PDs reflect the flexibility of HEIs to respond to the demands and needs of PD students, and to the requirements of different professional contexts. Findings from the research reported that academics and managers in HEIs develop PD programmes in ways they see most effective for the professional groups being targeted, taking into consideration the available expertise and resources in their HEI to run such programmes. This diversity of impetus leads to increasing variations in the structure of individual PD programmes, with the entry requirements, credit allocations for component parts of PD programmes, training in research and other skills and knowledge, and the allocation of supervision hours often differing from programme to programme. Throughout the discussion, I argue that the seemingly endless development of new PD programmes has led to the creation of tensions around PD provision that, if left unaddressed, will threaten the future sustainability and credibility of PDs. These tensions add to those already raised by Burgess et al. (2011: 16), who question whether the impact of the PD leads to a close relationship between PD candidates and the workplace, with the outcome that the PD is of benefit to both parties, or whether the impact of the PD is more tenuous, leading, in some cases, to friction between the candidate and the workplace.

The future sustainability of professional doctorate programmes: Tensions around professional doctorate provision
While the growth of PD programmes within specialized areas can be seen as positive, suggesting that PDs are being developed in response to the demands of different professions and professionals, we cannot ignore the associated tensions that have arisen, which threaten the future sustainability of PD programmes.
Tension 1: The wide range of PD titles and variety in structure of PD programmes leads to a lack of common understanding of the purpose and value of PDs. It was acknowledged earlier in the paper that the range of PD programme titles and awards offered is expanding, with variations in nomenclature being characteristic of PDs in all subject areas. In relation to the EdD, for example, both Fell et al. (2011) and the findings of the study on which this paper is based (Mellors-Bourne et al., 2016) reported that several different programme titles and awards were encompassed within the EdD category. These include: professional doctorate in (or of) education; doctorate in (or of) education; and education doctorate. In some cases, the titles also include a suffix, such as professional doctorate in education: leadership and management.
This proliferation of PD titles and awards, and increasing inconsistency in the structure and requirements of different PDs, even within similar subject areas, makes it difficult to clearly articulate the purpose of PDs, the theoretical and methodological contributions they make, and the value they add to professional practice. This leads to confusion among potential PD candidates and employers. The task of building a common understanding around what PD study entails, the standard of study required, and what PDs can offer to potential candidates and their employers, will become progressively more difficult unless the trend for the increasing diversity of PDs is reversed. If confidence in the purpose and worthiness of PDs is to grow, overarching key characteristics that identify and define their purpose, value and contribution need to be more clearly articulated and communicated to all stakeholders.
Tension 2: Difficulties in recruiting sufficient numbers of supervisors and examiners within niche areas of professional practice. Where an HEI develops a PD programme within a specialized area to cater for the needs of specific types of professionals, this may lead to challenges around being able to allocate sufficient supervisors who are knowledgeable about the area. There may also be difficulties in recruiting appropriate internal and external examiners with expertise within the small niche area of research and professional practice encompassed within the PD programme.
Tension 3: PD programmes that enrol small numbers of candidates are not financially viable. Given that large numbers of relatively new (within the last five years) PD programmes either fail to enrol candidates, or fail to enrol sufficient numbers of candidates to run financially viable programmes, there is a risk that newly developed programmes, especially those within very niche areas, will be untenable for HEIs to offer on a long-term basis. Within all HEIs in England, costs are closely monitored and there is increasing pressure on HEI managers for programmes to at least 'break even', if not make a profit. Running programmes with very small cohorts is not a cost-effective way of operating for HEIs, and leads to heightened concerns over the viability of such programmes.
With reference to a sample of 25 EdD programmes (included within the overall sample of 100 PD programmes scrutinized as part of the HEFCE-commissioned research), it was found that in the 2013/14 academic year there was an average of only six new starters per EdD programme, with no starters recorded within one in five EdD programmes. It was acknowledged by senior managers in HEIs that, due to the increasingly difficult financial climate, programmes operating at a financial loss are under threat. However, it was also recognized that in the case of the EdD, senior managers of HEIs are likely to continue running EdD programmes if they are undertaken by members of staff at the HEI, even where the programmes are running at a financial loss. In such cases, the EdD is seen as a means of increasing the skill set of their workforce and, although it may not be cost-effective in financial terms, it is considered to benefit the staff enrolled on the programme and the HEI more generally. However, other PD programmes running at a financial loss were not viewed in such a favourable way, and there was uncertainly around the future of these programmes.
Tension 4: Attempts to counteract the negative financial implications of low enrolment will reduce the positive aspects of the cohort experience favoured by students. Within some HEIs, attempts are being made to counteract the financial implications of small cohorts by, for example, combining the teaching of candidates in such cohorts with teaching on other programmes. While this helps to address the financial burden of small cohorts, it also reduces the known benefits of face-toface cohort programme delivery, which is often regarded by PD candidates as one of the most enjoyable, supportive and valuable aspects of their PD experience.
Other attempts to counteract the negative financial implications of low enrolments on PD programmes involve broadening the geographical area from which HEIs attempt to recruit candidates. Even though candidates may continue to be part of a cohort and meet for structured sessions during residential weekends/weeks, they will be less likely to profit from face-to-face contact with other cohort members on a more frequent basis. While not dismissing the reported advantages of online discussion forums for PD candidates involved in online programmes, the consequences of recruiting candidates from a wide geographical area will mean that supervision and programme delivery is likely to be conducted at a distance, with the outcome that the benefits of face-to-face cohort experience are lost.
With reference to the EdD, senior academics and administrators in HEIs reported that some EdD programmes are being specifically developed for very local niche contexts and markets, while others are being developed with the aim of attracting more international audiences. However, regardless of the potential candidates in mind, the motive for developing the programmes was primarily to attract candidates as a means of bringing income into the HEI, with the student experience seemingly being a secondary consideration. More thought needs to be given to the long-term impact on recruitment, and on the student experience, if the positive aspect of the cohort experience, regularly reported by PD candidates as one of the most enjoyable and effective learning experiences, will no longer be a component part of the PD.

Conclusion
The proliferation of titles of PD awards and programmes, and inconsistencies between the various programmes, has resulted in a lack of clear articulation and understanding in terms of what PDs are, the theoretical and methodological contribution they make, and the value they add to professional practice. This has led to confusion and an overall weak profile of PDs. This weak profile is compounded as a result of the large numbers of PD programmes, often in very niche areas, being either unable to recruit, or recruiting only very small numbers of students. Such low recruitment rates threaten the viability of many PD programmes, and this unstable platform on which PDs sit decreases the likelihood of PD programmes featuring, in any significant way, in HEI strategies for future development. Consideration needs to be given to merging subject-specific PDs into recognizable types, and to clearly defining the characteristics that identify these, while also articulating their value and benefits to potential PD candidates and the wider workforce. For example, in the case of EdDs, steps could be taken to reduce the range of EdD programmes available, with the introduction of some generic threads that run through all EdD programmes. Those working in professional educational contexts could then be made aware of these characteristics, and of the difference EdD study can make to candidates, and to the professional practice and policy contexts within the settings in which they are situated.