Impact of the palliative care clinical nurse specialist on patients and relatives: a stakeholder evaluation

Impact of the palliative care clinical nurse specialist on patients and relatives: a stakeholder evaluation Barbara Jack, Jackie Oldham, Anne Williams

Within the last decade, there has been a rapid expansion in the United Kingdom of clinical nurse specialists (CNSs), yet there has been limited evidence of their effectiveness.The clinical area of palliative care has one of the largest numbers of CNSs which has particularly started to escalate in the acute hospital setting. Following the Calman-Hine Report and the more recent NHS Cancer Plan, it is anticipated that the number of CNSs in palliative and cancer care is likely to grow. In light of the current policy emphasis of Clinical Governance and Clinical Effectiveness, there is an urgent need to demonstrate the contribution that CNSs make. This paper presents the qualitative findings of an evaluation study on the impact of the CNS within a palliative care team in a large acute hospital in the North-West of England. A stakeholder evaluation that encompassed tape-recorded semi-structured interviews to explore how the stakeholders saw the impact of the CNS within palliative care was performed.Twenty-seven interviews were conducted with stakeholders across the hospital setting including senior nurses, consultants, junior doctors and nurses representing the different grades. Data were analysed for emerging themes utilizing a case and cross-case analysis. The results indicated that the CNSs within palliative care in an acute hospital are seen to be potentially beneficial for both patients and relatives.This paper will focus on exploring these perceived benefits, which included symptom control, psychological care and being an advocate for patients and relatives. r 2002 Elsevier Science Ltd. All rights reserved. Keywords: palliative care, acute hospital, CNSs, stakeholder evaluation

Barbara Jack Senior Lecturer /Research Fellow*, BSc (Econ) Hons, Msc, PhD, RGN, DPSN RNT, PGDE, Edge Hill College, School of Health Studies,University Hospital Aintree, Longmoor Lane, Liverpool L9 7AL, UK (* Joint Appointment with the Marie Curie Centre, Liverpool) Tel: +44 151 529 3455 E-mail:[email protected] Jackie Oldham BSc (Hons), PhD, RGN, Centre For Rehabilitation Science, University of Manchester, Manchester Royal Inf|rmary, Oxford Road, Manchester M13 9W1, UK Anne Williams BA, MA PhD, RGN, RM, School of Health Science, University of Wales, Swansea, Singleton Park, Swansea SA2 8PP, UK Correspondence and o¡print requests to: Barbara Jack

Die Auswirkungen palliativer Manahmen durch speziell ausgebildete Pflegekrfte auf Patienten und deren Angeh˛rige: eine Befragung beim betroffenen Krankenhauspersonal Der Einsatz von speziell ausgebildeten Pflegekrften im Krankenhaus (Clinical Nurse Specialists -- CNS) hat in den letzten zehn Jahren in Grobritannien sehr stark zugenommen. Allerdings konnte die Effizienz ihrer Arbeit bisher nur in begrenztem Ausma nachgewiesen werden. CNS-Krfte fˇhren vor allem palliative Manahmen durch, wobei sich besonders ihr Einsatz in Unfallkrankenhusem deutlich verstrkt hat. Sowohl der CalmanHine-Bericht als auch der spter erschienene ‘Cancer Plan’ des Nationalen Gesundheitsdienstes NHS haben vorhergesagt, dass der Beschftigungsgrad dieser Spezialpflegekrfte im Bereich von palliativen Manahmen und Krebsbetreuung wahrscheinlich steigen wird. Unter dem Aspekt, dass der gegenwrtige politische Schwerpunkt im Krankenhaussektor auf mehr Fˇhrungsqualitt und Effektivitt liegt, scheint es dringend angebracht, den Beitrag des CNS-Personals deutlich hervorzuheben. Dieser Artikel referiert die Ergebnisse einer Studie ˇber die Effizienz des Einsatzes von CNS-Krften innerhalb eines Pflegeteams im Bereich palliativer Manahmen an einem groen Unfallkrankenhaus im Nordwesten Englands. 27 reprsentativ ausgewhlte Angeh˛rige des betroffenen medizinischen und administrativen Krankenhauspersonals wurden ˇber ihre Sichtweise zu dem Komplex befragt. Die Interviews waren teilstrukturiert und wurden auf Band mitgeschnitten. Dann wurden die Daten mit Hilfe einer gesonderten Fallanalyse auf thematische Schwerpunktbildungen hin untersucht. Die Ergebnisse zeigen, dass der Einsatz von CNS-Krften im Unfallkrankenhaus sowohl fˇr Patienten als auch fˇr deren Angeh˛rige als durchaus vorteilhaft angesehen wird, und zwar im Hinblick auf Symptomkontrolle, psychologische Betreuung und Vertretung der Betroffenen. Das Hauptaugenmerk dieses Artikels bildet die Untersuchung und Darstellung der genanntenVorteile.

European Journal of Oncology Nursing 6 (4), 236 ^242 # 2002 Elsevier Science Ltd. All rights reserved. doi:10.1054/ejon.2002.0214, available online at http://www.idealibrary.com on

Impact of palliative care clinical nurse specialist 237

INTRODUCTION The last decade has seen an increase in the number of qualified nurses who are directly involved in palliative and cancer care (Hill 2000). In particular, this development has been witnessed within the acute hospital setting, as a result of the expansion of hospital-based palliative care teams (Dunlop and Hockley 1998, Robbins 1998, Clark and Seymour 1999). This, in turn, has led to the establishment of dedicated hospital-based palliative care clinical nurse specialists (CNSs) (Cancer Collaboration 1997). Additional support for the expansion of hospital-based palliative care teams followed the publication of the Calman-Hine Report (1995). This resulted in the publication of the workforce and training implications for cancer care by the Cancer Collaboration (1997), which argued the need for more CNSs in palliative and cancer care. More recently, this support for more CNSs has increased with the publication by the Department of Health of the NHS Cancer Plan (Department of Health 2000a) and the Nursing Contribution to Cancer Care (Department of Health 2000b). The current emphasis of the UK government on clinical governance embraces the need to provide health care that can be shown to be clinically effective (NHS Executive 1999). Despite the increasing number of hospital-based palliative care teams, there is a paucity of research that evaluates them in comparison to traditional hospital-based care. The study by Ellershaw et al. (1995) demonstrated an improvement in patients’ reported symptoms following palliative care intervention. However, this study did not have a control group to allow comparison with normal care. Furthermore, there are no UK studies that have evaluated the impact of the hospital-based palliative care CNS. Expansion in the number of CNS posts has also been observed in a wide variety of other clinical specialities (Wilson-Barnett & Beech 1994, McGee et al. 1996, Castledine 1997). Castledine (1997) argues that expansion has resulted in the criteria for specialist practice being abused with confusion surrounding the term. As with palliative care, there are a paucity of research studies to demonstrate the effectiveness of the CNS. Existing studies have in the main compared the CNSs with traditional medically led care (Hill et al. 1994, WilsonBarnett and Beech 1994, Forster and Young 1996, Bredin et al. 1999, Horrocks et al. 2002). Although it is widely recognised that the evaluation of the post of CNS is problematic, owing to the complexity of attributing the change in the patient as being solely due to the impact of the CNS (Wilson-Barnett and Beech

1994), it is essential that any benefits of these posts be shown (Tierney et al. 1990, Ferguson 1997). Robbins (1998) argues that it is unclear as to what extent the specialist nurse offers a different service from a non-specialist. Furthermore, Ferguson (1997) has stressed that there are an increasing number of unanswered questions about CNSs by commissioning authorities. This, along with the drive for clinical effectiveness, has resulted in the demand for confirmation of the benefits that they provide (Tierney et al. 1990, Ferguson 1997, Robbins 1998, Hill 2000). This study forms part of a doctoral thesis that evaluated the impact of hospital-based palliative care CNSs (Jack 2001). The study included evaluating the impact that CNSs had on patients’ symptoms and insight scores. This paper focuses upon exploring the stakeholders (doctors and nurses) views of the impact that the CNS makes. Inclusion of the stakeholders’ views embraces the argument put forward by Tierney et al. (1990) that the CNS has to demonstrate to both clinical peers and administrators the value of their contribution.

METHODOLOGY The study took place in a large (1300 beds) NHS hospital in the North-West of England. The palliative care team consisted of four CNSs (who were based solely in the hospital), a consultant and a specialist registrar. At the time of the study, the team had been in existence for over 4 years. The aim of this phase of the evaluation study was to explore the doctors’ and nurses’ views of the impact of palliative care CNSs on patients and relatives within the acute hospital setting. A stakeholder evaluation approach was selected for the study as it enables the value or work of a service to be seen. The involvement of stakeholders in the evaluation process is argued as increasing their likelihood of acting upon the findings from the research (Patton 1987, 1990). Additionally, the involvement of stakeholders enables a plurality of perspectives to be obtained and increases the range and quantity of information available to the evaluator (Patton 1990, Clarke and Dawson 1999). It is generally accepted that stakeholder evaluation involves a qualitative research methodology approach. However, it is recognised that stakeholder evaluation requires careful planning, particularly regarding practical considerations in accessing the stakeholders (Patton 1987, 1990). These practical considerations were very important in the design of the study. Due to the limitation of available time (Rossi et al. 1999), the stakeholders holding only senior positions in the hospital had to be interviewed. This conEuropean Journal of Oncology Nursing 6 (4), 236 ^242

238 European Journal of Oncology Nursing

sideration, along with the potentially vast experience that the individual stakeholders may have had regarding the CNS, resulted in an approach that adhered to what Patton (1987, 1990) referred to as a philosophy of breadth rather than depth in order to include the views of all the key stakeholders.

Sample A purposive sample which focused upon the researchers conscious selection of certain subjects or elements to be included in the study was selected (Patton 1990, Polit et al. 2001). This was to ensure that a broad spectrum of both nursing and medical grades from the different specialities were included in the study. As CNSs in palliative care are not available in every hospital, staff who had been employed in the study hospital for under 6 months were excluded from the study. Additionally, the criteria of 6 months postqualification for nurses and 12 months for doctors was selected to ensure that they would have had chance to experience the effects of the CNS working in palliative care. Consultants who held joint appointments with other hospitals were excluded from the study. This was decided as the other hospital could have a different structure to the organization and delivery of palliative care services that could inadvertently influence the consultant’s views.

The selected sample for the study Having identified that there was a need to include stakeholders from various positions within the hospital, consideration was made to whom to approach. Clearly, there were stakeholders who held key positions, for example senior nurses, who would be approached to be included in the study. However, the selection of medical and nursing staff was made on the basis of trying to cover as many different areas of the hospital that the CNSs covered, thus obtaining a broad picture of their intervention. Similarly, clinical areas for example the intensive care unit, accident and emergency department, and mental health, where the CNS did not usually have any patient contact, were excluded from the study. Opportunistic sampling was used to recruit nurses and non-consultant medical staff who met the inclusion criteria to the study. Consultant recruitment was made by direct contact with the consultants (at the time of the study, hospital reorganization was occurring which resulted in several consultants being unable to commit time to be a part of the study).

Data collection and analysis The approach adopted for the study was that proposed by Patton (1987, 1990), of a standarEuropean Journal of Oncology Nursing 6 (4), 236 ^242

dised open-ended interview. Taking the respondents through the same questions, with the inclusion of probing questions, ensured that the interview time was used to the full. Preliminary discussions with key stakeholders indicated they were only prepared to be interviewed for a maximum of 30 minutes. Had a more unstructured interview format been used, the interview would have taken longer and would have been less acceptable to the key stakeholders, with the concomitant loss of data both in terms of volume and quality. For this phase of the study the interview guide focused upon exploring the question ‘‘Thinking of your experience of the CNS within the palliative care team what do you see as their effect upon patients and relatives?’’. Respondents were prompted to give clinical examples where appropriate. All the interviews were conducted by one researcher, and took place in the hospital setting (Jack 2001). Audio tape recording of the interview was selected to ensure that a record of the entire interview was available and to overcome potential information being lost. A hybrid approach was selected for the data analysis process (a summary of this is contained in Table 1) that drew upon various approaches suggested in the literature (Collaizzi 1978, Patton 1987 and 1990, May, 1998). This approach contained the four stages: organization, familiarisation, reduction and analysis. The reduction stage introduced coding to the data, categories under each question were identified and subsequently numerically coded (May 1998). The additional code [c] for clinical examples was also introduced when an example was given by the respondent to illustrate their comments. This coding system is summarised in Table 2. To increase the credibility of the data collection and analysis of the study, the transcribed interviews were returned to the respondents for checking and alteration if they so wished (May 1998). The analysis stage used what Patton (1987, 1990) referred to as case and cross-case analysis. This approach meant that each interview was considered as a separate case and then compared to other cases to ascertain variations in answers. Having coded all the transcripts and looked at each case individually, cross-case analysis was undertaken. This was where the transcripts were compared with each other. The transcripts were looked at in categories that related to the position that the respondents held, i.e., junior nurses, ward managers, nurse managers, junior doctors and consultants. Combinations of groups for example, junior nurses and ward managers, were also analysed in comparison with nurse managers. This enabled the identification of specific points to be looked at with regard to the position that the stakeholders held.

Impact of palliative care clinical nurse specialist 239 Table 1 A framework for qualitative stakeholder evaluation (Adapted from Collaizzi 1978, Patton 1987, 1990, May 1998) Stage One : Organisation Ensure all audio tapes clearly labelled and transcribed Check transcriptions against the audio tape [essential stage if externally transcribed] Send draft transcription to respondents for corrections Final draftFensure multiple copies made and stored separately StageTwo : Familiarisation Thorough reading of the narrative to aid familiarisation Commence f|rst thoughts list of potential thoughts/ideas that may arise during this process Check f|eld/re£exive dairy kept during data collection phase for any key notes made Gain sense of the narrative and identify potential topics/emerging themes Start a preliminary list of categories StageThree : Reduction Review narrative and reduce to signif|cant statements Reduce data to the smallest points that can stand on their own Apply preliminary categories/codes list to the reduced points/statements Review preliminary category/codes list and expand as required Apply completed category/codes list to the reduced data Stage Four : Analysis Complete cross-case and case analysis of the data Identify any emerging themes and patterns Return to original complete narrative to ensure a completeness of data ConclusionFdraw up signif|cant themes and patterns

Table 2 The coding framework

THE RESULTS

1. Demographic data 1.1. Post held 1.2. Years in post

In total, 27 stakeholders were included in the study, the sample included senior nurses holding both clinical (Clinical Service Managers) and managerial posts (Director of Nursing) as well as ward nursing staff of all grades based upon the acute wards across the hospital. Additionally, medical staff were included from the acute clinical areas (Table 3 illustrates the selected sample for the study). The research ethics committee granted approval for the study and verbal consent was obtained from each subject. Several themes emerged from the analysis of data that related to the impact of the palliative care CNS on patients and relatives/carers. These included the effect upon physical symptoms, psychological care, specific care of relatives and an advocacy effect. For this phase of the study,

2. E¡ect on patients 2.1. Physical 2.1.1. Pain 2.1.2. Nausea 2.1.3. Other 2.2. Psychological 2.2.1. Terms used 2.2.2. Dying 2.2.3. Coping 3. Relatives 3.1. Information 3.2. Support 3.3. Caring 4. Advocate 4.1. Information 4.2. Verbal/practical

Table 3 The sample selected for the study Nursing sta¡ (Speci¢c post-holders)

Medical Sta¡ Consultants

Director of Nursing Assistant Director

1 1

Medicine Surgery Elderly Palliative care Medical

Clinical Services Manager (Medicine) Clinical Services Manager (Surgery)

1 1

G F E D

Doctors 1 1 1 1

Medicine Surgery Elderly Palliative care

Nursing sta¡ (Directorate and Grade) Surgical Grades of nurses 2 G 1 F 3 E 2 D

1 1 1 1

2 1 2 2

European Journal of Oncology Nursing 6 (4), 236 ^242

240 European Journal of Oncology Nursing

there was found to be general consensus between the different categories of respondents following the case and cross-case analysis. However, the advocacy effect was generally identified by staff who were clinically, rather than managerially based.

Physical symptoms and psychological care All the respondents, irrespective of grade, identified physical symptom relief, in particular pain relief. One example was given by an F grade ward manager who stated: ‘‘The palliative care nurse will be there to guide and listen to the patient and to adjust the medication until the patient is pain free.’’

A Clinical Services Manager referred to the advanced knowledge that the CNS had to draw upon: ‘‘The palliative care nurses don’t just dive in with the MST (morphine sulphate tablets), they consider what is the most appropriate and often use sedatives and tranquillisers to maintain patient comfort.’’

All the respondents identified psychological care. Terms such as counselling, empathy, support and listening were used. ‘‘They tend to sit down and talk to them more, talk to them straight as well. Whereas I think nurses are, you know, a little afraid to do that when they are dealing with dying patients. They will get relatives in and sit down with them and given them some straight answers, whereas I find it difficult to do that.’’ [E Grade]

Additionally, one consultant commented that ‘‘A nurse specialist is trained in how to handle and convey information to patients with terminal illness y they have the patience, the time and the skill to convey information in a way that the patient will accept. y the ability of the individual patient to handle their cancer problem is the main area where they are going to have success. Many patients turn and face the wall, they just can’t cope with the idea of cancer, they have got no idea that there is very often a considerable period of useful time left.’’ [Consultant]

Relatives and carers Ten respondents elaborated upon the specific care of the relatives. A medical consultant who gave an example of this said: ‘‘Important part also is to convey the information to the relatives, which will allow the relatives to discuss the illness with their afflicted relative y allowing them both to speak to each other.’’ [Consultant]

This was supported by the clinical staff, one ward manager said: ‘‘If the patient sees that the family are being supported alongside the patient then quite often this European Journal of Oncology Nursing 6 (4), 236 ^242

can alleviate in some way the emotional and spiritual and social distress that accompanies an illness such as cancer.’’ [Ward Manager–Medicine]

An advocate for patients and relatives Several of the respondents, particularly those who were clinically based, referred to the CNSs acting as an advocate for both patients and relatives. This support included explaining to both groups about the different palliative care treatments available, as illustrated by one staff nurse stating that: ‘‘Everybody understands pain relief, but they don’t understand that surgery or DXT [deep X-Ray Therapy] treatment will be used as a form of palliative care y’’

Reference was also made by the ward-based staff, to the CNSs spending time with the relatives discussing the discharge options that were available. This included exploring the place of death if appropriate as well as the support that was available for the family.

DISCUSSION Results indicate that stakeholders perceive the palliative care CNSs as potentially having a positive impact for both patients and relatives. In particular, all the respondents referred to the invaluable impact of the palliative care CNS with respect to improving symptom control. Reference to the CNS having additional knowledge surrounding the management of symptoms, was made by several of the respondents. This identified benefit of providing symptom control is in keeping with the findings of Ellershaw et al. (1995), although this study did not focus specifically on CNSs, it did, however, report an improvement in patients’ symptoms following intervention by a hospital-based palliative care team. Stakeholders highlighted the potential benefit of the CNS providing psychological care for the patients. This included empathy and support, but also the provision of information. One medical consultant referred to the CNS as possessing the skills to impart this information. Additionally, this input also resulted in the CNS appearing to be an advocate for patients and relatives with regards to explaining treatment interventions, such as radiotherapy and chemotherapy, but also discussing options that are available surrounding the place of the forthcoming death. Stakeholders also elaborated upon the care of relatives provided by the palliative care CNS. The importance of this input was stressed by one medical consultant and further illustrated by a

Impact of palliative care clinical nurse specialist 241

ward sister with an example of helping a family to come to terms with an impending death. These finding relating to psychological care and the care of the relatives are supported by Ellershaw et al. (1995) study, where an increase in insight in relation to both diagnosis and prognosis by patients’ and their relatives following palliative care team intervention is observed.

Limitations of the study and recommendations for further research There are limitations to the design of the study that need to be taken into consideration when interpreting the results. The study was only conducted in one acute hospital setting, and it is acknowledged that there is a wide variation in the composition of hospital palliative care teams (Robbins 1998). Thus it is important to consider the specific influence that this design of team may have upon the findings. Further research with different palliative care team structures would be a useful comparison. Additionally, data collection only focused upon a short interview with the stakeholders due to the constraints of time. This did not allow for the whole context of the issues to be explored, nor did it allow the in-depth probing of responses, for example when reference was made to the provision of information by the CNSs, which an orthodox qualitative interview would have permitted. However, the large number of interviews that were conducted did ensure that a wide breadth of stakeholders views were obtained, including senior stakeholders within the organization. Additional qualitative research that included in-depth interviews, along with an observational element would enable findings to be extended to explore the actual input that CNSs make. Furthermore, exploring how patients and relatives perceive the contribution of the CNS would be valuable and provide valuable data on the input that the palliative care CNS makes within the acute hospital setting.

CONCLUSION This study has shown that stakeholders all perceive the palliative care CNS within the hospital setting, to provide added benefit to patients and their relatives particularly with regards to symptom control and psychological care. Although limitations are evident with regards to the design of the study, nevertheless, it does provide an insight into the effects that the palliative care CNSs are having in the acute hospital setting. This is an input that is arguably potentially beneficial and necessary, as it can help to improve the quality of life for patients during their final stages of life.

REFERENCES Bredin M, Corner J, Krishnasamy M, Plant H, Baily C, A’Hern R (1999) Multicentre randomized controlled trial of nursing intervention for breathlessness in patients with lung cancer. British Medical Journal 318: 901–904 Cancer Collaboration (1997) The workforce and training implications of the Calman/Hine Cancer Report. Cancer Collaboration, London Castledine G (1997) The abuse of specialist nursing titles must stop. British Journal of Nursing 6(19): 1137 Clark D, Seymour J (1999) Reflections on palliative care. Open University Press, Buckingham Clarke A, Dawson R (1999) Evaluation research: an introduction of principles, methods and practice. Sage Publications, London Colaizzi P (1978) Psychological research as a phenomenologist views it. In: Valle R, King M (Eds) Extential phenomenological alternatives for psychology. Oxford University Press, New York Department of Health (2000a) The NHS cancer plan. Department of Health, London Department of Health (2000b) The nursing contribution to cancer care. Department of Health, London Dunlop KJ, Hockley JM (1998) Hospital-based palliative care teamsFthe hospital–hospice interface, 2nd Edn. Oxford University Press, Oxford Ellershaw J, Peat S, Boys L (1995) Assessing the effectiveness of a hospital palliative care team. Palliative Medicine 9: 145–152 Expert Advisory Group on Cancer [The Calman-Hine Report] (1995) The policy framework for commissioning cancer services: a report by the Export Advisory Group on Cancer to the Chief Medical Officers of England and Wales. Department of Health and Welsh Office, London Ferguson A (1997) Clinical nurse specialists must show their worth. Information Exchange 22: 8 Forster A, Young J (1996) Specialist nurse supports for patients with stroke in the community: a randomised controlled trial. British Medical Journal 312: 1642–1646 Hill A (2000) The impact of expanding the numbers of clinical nurse specialists in cancer care: a United Kingdom case study. European Journal of Oncology Nursing 4(4): 19–226 Hill J, Bird H, Harmer R, Wright V, Lawton C (1994) An evaluation of the effectiveness, safety and acceptability of a nurse practitioner in a rheumatology outpatient clinic. British Journal of Rheumatology 33: 283–288 Horrocks S, Anderson E, Salisbury C (2002) Systematic review of whether nurse practitioners working in primary care can provide equivalent care to doctors. British Medical Journal 324: 819–823 Jack B (2001) An evaluation in an acute hospital setting of the impact of the clinical nurse specialist within a palliative care team. Unpublished PhD Thesis, University of Manchester May C (1998) The preparation and analysis of qualitative interview data. In: Roe B, Webb C (Eds) Research and development in clinical nursing practice. Whurr Publishers Ltd, London McGee P, Castledine G, Brown R (1996) A survey of specialist and advanced nursing practice in England. British Journal of Nursing 5(11): 82–86 NHS Executive (1999) Clinical governance in the new NHS. NHS Executive (HSC 1999/065) Patton MQ (1987) How to use qualitative methods in evaluation. Sage Publications, Beverley Hills, CA European Journal of Oncology Nursing 6 (4), 236 ^242

242 European Journal of Oncology Nursing Patton MQ (1990) Qualitative evaluation and research methods, 2nd Edn. Sage Publications, Beverley Hills, CA Polit D, Beck C, Hungler B (2001) Essentials of nursing research methods, appraisal and utilization, 5th Edn. Lippincott, Philadelphia, PA Robbins M (1998) Evaluating palliative careFestablishing the evidence base. Oxford University Press, Oxford

European Journal of Oncology Nursing 6 (4), 236 ^242

Rossi P, Freeman H, Lipsey M (1999) Evaluation a systematic approach, 6th Edn. Sage Publications, Beverley Hills, CA Tierney M, Grant L, Mazique S (1990) Cost accountability and clinical nurse specialist evaluation. Nurse Management 21(5): 26–31 Wilson-Barnett J, Beech S (1994) Evaluating the clinical nurse specialist: a review. International Journal of Nursing Studies 31(6): 561–571