A Case Study Evaluation Protocol to Assess Processes, Effectiveness and Impact of a Nurse Practitioner-Led Memory Clinic

The prevalence of dementia is predicted to increase significantly as the population ages and with no foreseeable cure options the burden of dementia will continue to grow. Early diagnosis provides many benefits, including timely access to appropriate support services and provision of tailored therapeutic interventions for people with dementia and their carers. Memory clinics are a key response to the need for specialist assessment and diagnosis of dementia. Multidisciplinary team memory clinics are considered the “gold standard”; however, such resource intensive clinics are likely unsustainable. The nurse-led memory clinic format may provide a primary care focused, diagnostic service for dementia that does not have the cost implications of multidisciplinary memory clinics but there is limited research using nurse practitioners. This study is exploring the potential of a nurse-led memory clinic as a primary health care approach to health promotion (brain health awareness), disease prevention (risk factor reduction) and early intervention (diagnosis and management of dementia). A realistic evaluation of a nurse practitioner-led memory clinic is described. Realistic evaluation is concerned not only with the outcomes of an intervention but also with the context and mechanisms of the intervention. We are using a mixed methods case study design to describe and evaluate the impact of the nurse practitioner-led memory clinic. The nurse practitioner in this study is an advanced practice aged care nurse who focuses on mental health, and dementia diagnosis, management and risk factor reduction. This study seeks to inform the development of an expanded scope role for nurse practitioners in assessment and referrals for dementia diagnosis. The heterogeneity of clients attending the nurse-led memory clinic will allow us to evaluate what works in the memory clinic, for whom, and under what circumstances, in what respects, and to what extent.

• Realistic Evaluation; Dementia Diagnosis; Nurse Practitioner; Memory Clinic; Australia

1. Introduction

In Australia, the prevalence of dementia is predicted to increase significantly as the population ages [1] [2] . Without preventative measures, the burden of dementia will continue to grow [3] . The potential demand on health services is enormous, given that 50 to 80 per cent of people with dementia are yet to receive a formal diagnosis [4] . The challenge for the health system is to develop cost-effective strategies for risk reduction and timely intervention [3] . Timely diagnosis of dementia is important as it enables people with dementia and their families to engage with appropriate support services, and receive tailored, therapeutic interventions [5] . A strong economic argument supports earlier diagnosis followed by timely interventions for people with dementia and their carers. A recent economic evaluation in the United Kingdom found significant cost savings and health benefits in early assessment for Alzheimer’s disease (AD) and pharmacological treatment of those with AD [6] . Furthermore, there are many non-pharmacological (that is, psychological, psychosocial and psychoeducational) interventions that can improve the quality of life for people with dementia and their carers [4] .

1.1. Issues in Early Diagnosis of Dementia in Primary Health Care

Primary health care is a comprehensive and cost-effective approach to health promotion, disease prevention and early intervention [7] . There are many factors relating to primary health care systems and primary health care providers that contribute to dementia diagnoses being missed or delayed in primary care [8] . The system factors include lack of resources (e.g., services and specialists) and financial constraints on primary health care providers (e.g., low financial reimbursement) [8] . Primary health care provider factors include knowledge gaps related to dementia care including the legal rights of patients [9] , lack of confidence to diagnose [10] , time to elicit a diagnosis [8] , and nihilistic attitudes regarding the benefits of a diagnosis [11] , all of which may contribute to diagnosis delays [9] . Specific barriers to dementia diagnosis by general practitioners (GPs), who in Australia are the key primary health care providers [12] , include varied presentations and causes of dementia, the time consuming nature of dementia diagnosis and subsequent counselling and service referral, along with additional social constraints such as stigmatization, social isolation and a perception that support services are rarely available [11] [13] [14] . As a result, GPs miss up to 70 per cent of early dementia or cognitive decline cases, with diagnostic delays from symptom onset of up to three years [13] [15] [16] . These missed diagnoses are problematic because early diagnosis provides benefits, such as people with dementia being able to make plans for care and deal with financial and legal matters while they retain adequate cognitive capacity, and the provision of tailored therapeutic interventions to increase quality of life for people with dementia and their carers [17] . Further, some GPs believe dementia care should be in the specialist domain [18] .

1.2. The Role of Memory Clinics

Memory clinics are seen as a key response to the need for specialist and timely assessment of dementia [19] . As a primary health care service, they have the potential to play an essential role in diagnosing dementia then supporting the person with dementia, and their carers [20] [21] . A memory clinic is “defined as an ambulatory assessment service dedicated solely to those with memory and related cognitive disorders” [22] , pp. 696-697. Memory clinics have continuously remodeled themselves since they were first described in the 1980s, reflecting different settings with varying clients and diverse activities undertaken [23] . Memory clinics have been used in urban and rural settings and range in their post diagnostic involvement [20] . Typically, out-patient memory clinics are available one or two days per week and headed by a doctor [22] [23] . Multidisciplinary memory clinics are commonly used to provide an effective and specialised approach to dementia diagnosis and early support [24] [25] . The multidisciplinary team includes a core team of clinicians, and often features a senior nurse and nonclinical support staff [22] [23] .

Woodward and Woodward [22] provided the first comprehensive description of Australian memory clinics, identifying twenty-three clinics, with most located in the state of Victoria, often staffed by neuropsychologists, geriatricians, and nurses. A clinic doctor typically undertook the initial assessment, with clients being seen, on average, three times (e.g., assessment, feedback, and follow-up) with assessment consultations generally lasting about four hours and feedback consultations taking about 45 minutes [22] . Multidisciplinary team memory clinics are considered the “gold standard”; however their financial viability has been questioned, with concerns that the resource intensive nature of such clinics is likely unsustainable [26] . With the burgeoning numbers of dementia cases, alternatives are needed [27] .

The concept of a nurse-led memory clinic is seeding globally and may provide a primary care focused, diagnostic service for dementia that does not have the cost implications of multidisciplinary services [19] [28] . There is an important distinction between nurses screening for dementia in memory clinics, as opposed to diagnosing dementia. The majority of published studies detail nurses conducting a screening assessment, which is assessed by specialists who provide the final diagnosis for clients. For example, Gonҫalves et al. [29] described research nurses providing home based assessments, the results of which were provided to experienced senior physicians who made a diagnosis following an examination and further tests as required. However, one United Kingdom study, which reported specialised nurses undertaking home based assessments, demonstrated that nurses can diagnosis dementia accurately (these nurses were found to detect dementia with 94 per cent accuracy and sub-diagnose dementia with 84 per cent accuracy when compared to multidisciplinary team diagnosis) [27] .

Given the relatively limited and sometimes conflicting evidence, further research is needed on expanding the role of advanced practice nurses to expedite the diagnosis of dementia and facilitate access to care pathways. There is potential for aged care nurse practitioners to fill this role [30] . Nurse practitioner roles have existed in the US and Canada since the 1960s, the UK followed in the 1980s [31] . In Australia, the first nurse practitioners were endorsed in the state of New South Wales in 2000 [32] . The title of nurse practitioner can only be used by a person who has been endorsed by the Australian Health Practitioners Regulation Agency. As at June 2013, there were approximately 926 endorsed nurse practitioners in Australia [33] . Nurse practitioners are experts in specific areas of nursing and have completed both advanced university study at a Master’s degree level and extensive clinical training to expand upon the traditional role of a Registered Nurse. These nurses use extended skills, knowledge and experience in the assessment, planning, implementation, diagnosis and evaluation of care required within in their specialised scope of practice.

A team of researchers and practitioners from the University of Tasmania and the Tasmanian Department of Health and Human Services is exploring the potential of a nurse-led memory clinic (NLMC) as a model of practice for nurse practitioners in aged care to address the rapidly rising demand for dementia specialist services and increase the numbers of Tasmanians receiving a timely dementia diagnosis. The nurse practitioner in this clinic is an advanced practice aged care nurse who focuses on mental health, and dementia diagnosis, management and risk factor reduction.

2. Methods

This paper describes the realistic evaluation design for the NLMC within a case study framework. Demographic and clinical data from clients, videorecording of consultations, clinic documentation, and interviews will be used to evaluate what works in the NLMC, for whom, and under what circumstances, in what respects, to what extent, and why [34] . Realistic evaluation is concerned not just with the outcomes of an intervention (in this case, a free assessment and management service for people with memory and cognitive changes) but also with the context and mechanisms of the intervention [35] -[37] . This is important because realistic evaluation “acknowledges that the outcomes of a project are confined to not only improved patient outcomes but also staff and organisational outcomes” [37] , p. 235. In the context of this study this is important because not only does the nurse-led memory clinic seek to improve access to primary health services for older persons, particularly those with dementia, but it also seeks to demonstrate in what ways an aged care nurse practitioner can add value to specialist dementia services with the provision of cost-effective holistic primary care.

2.1. Setting

The study is being conducted in collaboration with the Older Persons Mental Health Service (OPMHS) of the Tasmanian Department of Health and Human Services. The OPMHS provides a free and confidential mental health service to assist people over 65 years of age who have a mental illness and/or impaired cognitive functioning with challenging behaviour. The nurse-led memory clinic operates from the OPMHS southern site one day per week.

2.2. Model Design

The nurse-led memory clinic aims to provide an assessment and management service for people with memory and cognitive changes. Clients either self-refer or are referred by health professionals for assessment. The clinic offers a two-visit model and retains a primary health care focus by ensuring that general practitioners remain well-informed. The assessment is conducted by the nurse practitioner and involves taking a comprehensive history from the client and, importantly, a corroborative history from a relative, friend or primary carer. This is followed by the development of a personalized plan for those with identified cognitive deficits, which is prepared by the nurse practitioner. The nurse-led memory clinic model encourages referrals from general practitioners and maintains close links with GPs and specialists while providing support in the time consuming aspects of assessment, diagnosis and referral, and providing an alternative avenue for individuals to access initial assessment (Figure 1).

This memory clinic model adapts key features of two other models–self-referral and health professional referral. Self-referral by community members is used by the community memory clinics developed by The Research Institute for the Care of the Elderly at St Martin’s Hospital in Bath, UK [38] . Health professional referral is used by most other memory clinic services.

The NLMC assessment process results in one of four diagnoses for clients and these will be used as criteria for validation:

Ÿ  Dementia—a probable Alzheimer’s like dementia based on DSM IV-TR diagnostic criteria for the diagnosis of Alzheimer’s disease [39] . While the nurse practitioner may identify clinical signifiers suggestive of a differential diagnosis, and may indicate this in the diagnosis, the purpose of the clinic is to identify whether the client has a dementia type illness and to refer appropriately.

Ÿ  Mild cognitive impairment/possible dementia when a patient has subtle but definite cognitive deficits as demonstrated on cognitive screening tests and/or history but these are not of a degree that warrant a diagnosis of dementia.

Ÿ  A picture not typical of a dementing illness but where significant physical or psychiatric disability is identified warranting further specialist assessment, e.g. severe depressive illness.

Ÿ  No dementia.

2.3. Study Design

We are using a mixed methods case study design to describe and evaluate the impact of the nurse practitioner led memory clinic [40] . Case study methods are widely used in health and social care research and are increa-

References

1. Jorm, A.F., Dear, K.B. and Burgess, N.M. (2005) Projections of Future Numbers of Dementia Cases in Australia with and without Prevention. Australian and New Zealand Journal of Psychiatry, 39, 959-963.http://dx.doi.org/10.1080/j.1440-1614.2005.01713.x

2. Access Economics (2009) Keeping Dementia Front of Mind: Incidence and Prevalence 2009-2050.http://www.fightdementia.org.au/common/files/NAT/20090800_Nat__AE_FullKeepDemFrontMind.pdf

3. Nepal, B., Ranmuthugala, G., Brown, L. and Budge, M. (2008) Modelling Costs of Dementia in Australia: Evidence, Gaps, and Needs. Australian Health Review, 32, 479-487.http://dx.doi.org/10.1071/AH080479

4. Prince, M.J., Bryce, D.R. and Ferri, C.P. (2011) The Benefits of Early Diagnosis and Intervention.http://www.alz.co.uk/research/WorldAlzheimerReport2011.pdf

5. Burns, A. and Iliffe, S. (2009) Alzheimer’s Disease. British Medical Journal, 338, b158. http://dx.doi.org/10.1136/bmj.b158

6. Getsios, D. (2012) An Economic Evaluation of Early Assessment for Alzheimer’s Disease in the United Kingdom. Alzheimer’s & Dementia, 8, 22-30. http://dx.doi.org/10.1016/j.jalz.2010.07.001

7. Labonté, R., Pooyak, S., Baum, F., Schaay, N., Packer, C., Laplante, D., et al. (2008) Implementation, Effectiveness and Political Context of Comprehensive Primary Health Care: Preliminary Findings of a Global Literature Review. Australian Journal of Primary Health, 14, 58-67. http://dx.doi.org/10.1071/PY08037

8. Bradford, A., Kunik, M., Schulz, P., Williams, S. and Singh, H. (2009) Missed and Delayed Diagnosis of Dementia in Primary Care: Prevalence and Contributing Factors. Alzheimer Disease & Associated Disorders, 23, 306-314.http://dx.doi.org/10.1097/WAD.0b013e3181a6bebc

9. Hansen, E., Robinson, A., Mudge, P. and Crack, G. (2005) Barriers to the Provision of Care for People with Dementia and Their Carers in a Rural Community. Australian Journal of Primary Health, 11, 72-79.http://dx.doi.org/10.1071/PY05010

10. Mitchell, A.J., Meader, N. and Pentzek, M. (2011) Clinical Recognition of Dementia and Cognitive Impairment in Primary Care: A Meta-Analysis of Physician Accuracy. Acta Psychiatrica Scandinavica, 124, 165-183.http://dx.doi.org/10.1111/j.1600-0447.2011.01730.x

11. Hansen, E.C., Hughes, C., Routley, G. and Robinson, A.L. (2008) General Practitioners’ Experiences and Understandings of Diagnosing Dementia: Factors Impacting on Early Diagnosis. Social Science & Medicine, 67, 1776-1783.http://dx.doi.org/10.1016/j.socscimed.2008.09.020

12. Wiese, M., Jolley, G., Baum, F., Freeman, T. and Kidd, M. (2011) Australia’s Systems of Primary Healthcare—The Need for Improved Coordination and Implications for Medicare Locals. Australian Family Physician, 40, 995-999.http://search.informit.com.au/documentSummary;dn=686937046799945;res=IELHEA

13. Bond, J., Stave, C., Sganga, A., O’Connell, B. and Stanley, R.L. (2005) Inequalities in Dementia Care across Europe: Key Findings of the Facing Dementia Survey. International Journal of Clinical Practice, Supp. 59, 8-14.http://dx.doi.org/10.1016/j.socscimed.2008.09.020

14. Greenway-Crombie, A., Snow, P., Disler, P., Davis, S. and Pond, D. (2012) Influence of Rurality on Diagnosing Dementia in Australian General Practice. Australian Journal of Primary Health, 18, 178-184.http://dx.doi.org/10.1071/PY12008

15. Ganguli, M., Rodriguez, E., Muslant, B., Richards, S., Pandav, R., Vander Bilt, J., et al. (2004) Detection and Management of Cognitive Impairment in Primary Care: The Steel Valley Seniors Survey. Journal of the American Geriatrics Society, 52, 1668-1675. http://dx.doi.org/10.1111/j.1532-5415.2004.52459.x

16. Valcour, V.G., Masaki, K.H., Curb, J.D. and Blanchette, P.L. (2000) The Detection of Dementia in the Primary Care Setting. Archives of Internal Medicine, 160, 2964-2968. http://dx.doi.org/10.1001/archinte.160.19.2964

17. Brodaty, H. (2007) Early Diagnosis of Dementia.http://www.fightdementia.org.au/common/files/NAT/20070300_Nat_NP_10EarlyDiagnDem.pdf

18. Turner, S., Iliffe, S., Downs, M., Wilcock, J., Bryans, M., Levin, E., Keady, J. and O’Carroll, R. (2004) General Practitioners’ Knowledge, Confidence and Attitudes in the Diagnosis and Management of Dementia. Age and Ageing, 33, 461-467. http://dx.doi.org/10.1093/ageing/afh140

19. Christian, D. (2009) Nurse-Led Memory Clinics Set to Improve Dementia Care in England. Nursing Older People, 21, 5.

20. Szymczynska, P., Innes, A., Mason, A. and Stark, C. (2011) A Review of Diagnostic Process and Postdiagnostic Support for People with Dementia in Rural Areas. Journal of Primary Care & Community Health, 2, 262-276.http://dx.doi.org/10.1177/2150131911404705

21. Lee, L., Hillier, L., Stolee, P., Heckman, G., Gagnon, M., McAiney. C. and Harvey, D. (2010) Enhancing Dementia Care: A Primary Care-Based Memory Clinic. Journal of the American Geriatrics Society, 58, 2197-2204.http://dx.doi.org/10.1111/j.1532-5415.2010.03130.x

22. Woodward, M.C. and Woodward, E. (2009) A National Survey of Memory Clinics in Australia. International Psychogeriatrics, 21, 696-702. http://dx.doi.org/10.1017/S1041610209009156

23. Jolley, D., Benbow, S.M. and Grizzell, M. (2006) Memory Clinics. Postgraduate Medical Journal, 82, 199-206.http://dx.doi.org/10.1136/pgmj.2005.040592

24. Phipps, A.J. and O’Brien, J.T. (2002) Memory Clinics and Clinical Governance—A UK Perspective. International Journal of Geriatric Psychiatry, 17, 1128-1132. http://dx.doi.org/10.1002/gps.761

25. Wolfs, C.A.G., Dirksen, C.D., Severens, J.L. and Verhey, F.R.J. (2006) The Added Value of a Multidisciplinary Approach in Diagnosing Dementia: A Review. International Journal of Geriatric Psychiatry, 21, 223-232.http://dx.doi.org/10.1002/gps.1454

26. Gladman, J.R.F., Jones, R.G., Radford, K., Walker, E. and Rothera, I. (2007) Person-Centred Dementia Services Are Feasible, but Can They Be Sustained? Age and Ageing, 36, 171-176. http://dx.doi.org/10.1093/ageing/afl161

27. Page, S., Hope, K., Bee, P. and Burns, A. (2008) Nurses Making a Diagnosis of Dementia—A Potential Change in Practice? International Journal of Geriatric Psychiatry, 23, 27-33. http://dx.doi.org/10.1002/gps.1831

28. Hain, D., Dunn, D. and Tappen, R. (2011) Patient-Provider Partnership in a Memory Disorder Center. Journal of the American Academy of Nurse Practitioners, 23, 351-356. http://dx.doi.org/10.1111/j.1745-7599.2011.00619.x

29. Gonalves D., Arnold E., Appadurai K. and Byrne, G.J. ,et al. (2011)Case Finding in Dementia: Comparative Utility of Three Brief Instruments in the Memory Clinic Setting International Psychogeriatrics 23, 788-796.

30. Arbon, P., Bail, K., Eggert, M., Gardner, A., Hogan, S., Phillips, C., et al. (2009) Reporting a Research Project on the Potential of Aged Care Nurse Practitioners in the Australian Capital Territory. Journal of Clinical Nursing, 18, 255-262. http://dx.doi.org/10.1111/j.1365-2702.2008.02452.x

31. Driscoll A., Worrall-Carter L., O’Reilly J. and Stewart, S ,et al. (2005)A Historical Review of the Nurse Practitioner Role in Australia Clinical Excellence for Nurse Practitioners 9, 141-152.

32. Australian College of Nurse Practitioners (2014) History. http://acnp.org.au/history

33. Nursing and Midwifery Board of Australia (2013) Statistics.http://www.nursingmidwiferyboard.gov.au/About/Statistics.aspx

34. Wong, G., Greenhalgh, T., Westhorp, G. and Pawson, R. (2012) Realist Methods in Medical Education Research: What Are They and What Can They Contribute? Medical Education, 46, 89-96.http://dx.doi.org/10.1111/j.1365-2923.2011.04045.x

35. Douglas, F.C., Gray, D.A. and van Teijlingen, E.R. (2010) Using a Realist Approach to Evaluate Smoking Cessation Interventions Targeting Pregnant Women and Young People. BMC Health Services Research, 10, 49.http://dx.doi.org/10.1186/1472-6963-10-49

36. Pawson, R. and Tilley, N. (1997) Realistic Evaluation. Sage Publications, London.

37. Wand, T., White, K. and Patching, J. (2010) Applying a Realist(ic) Framework to the Evaluation of a New Model of Emergency Department Based Mental Health Nursing Practice. Nursing Inquiry, 17, 231-239.http://dx.doi.org/10.1111/j.1440-1800.2010.00488.x

38. The Research Institute for the Care of the Elderly (2011-2014) Memory Clinic. http://www.rice.org.uk/memory+clinic

39. McKeith, I., Glasako, D., Kosaka, K., Perry, E., Dickson, D., Hansen, L., et al. (1996) Consensus Guidelines for the Clinical and Pathologic Diagnosis of Dementia with Lewy Bodies (DLB): Report of the Consortium on DLB International Workshop. Neurology, 47, 113-124. http://dx.doi.org/10.1212/WNL.47.5.1113

40. Gardner, G., Carryer, J., Dunn, S. and Gardner, A. (2004) The Nurse Practitioner Standards Project. Australian Nursing and Midwifery Council, Canberra.

41. Anthony, S. and Jack, S. (2009) Qualitative Case Study Methodology in Nursing Research: An Integrative Review. Journal of Advanced Nursing, 65, 1171-1181. http://dx.doi.org/10.1111/j.1365-2648.2009.04998.x

42. Yin, R.K. (2008) Case Study Research: Design and Methods. 4th Edition, Sage Publications, Thousand Oaks.

43. Bergen, A. and While, A. (2000) A Case for Case Studies: Exploring the Use of Case Study Design in Community Nursing Research. Journal of Advanced Nursing, 31, 926-934. http://dx.doi.org/10.1046/j.1365-2648.2000.01356.x

44. Caris-Verhallen, W.M.C.M., Kerkstra, A., Bensing, J.M. and Grypdonck, M.H.F. (2000) Effects of Video Interaction Analysis Training on Nurse-Patient Communication in the Care of the Elderly. Patient Education and Counseling, 39, 91-103. http://dx.doi.org/10.1016/S0738-3991(99)00094-4

45. Cameron N. and McMillan, R ,et al. (2006)Enhancing Communication Skills by Peer Review of Consultation Videos Education for Primary Care 17, 40-48.

46. Martin-Khan M., Varghese, P., Wootton, R. and Gray, L. (2008) Physical Examination and Diagnosis of Dementia for Video Consultation. Journal of the American Geriatrics Society, 56, 947-949.http://dx.doi.org/10.1111/j.1532-5415.2008.01658.x

47. Fine, E., Reid, M.C., Shengelia, R. and Adelman, R.D. (2010) Directly Observed Patient-Physician Discussions in Palliative and End-of-Life Care: A Systematic Review of the Literature. Journal of Palliative Medicine, 13, 595-603. http://dx.doi.org/10.1089/jpm.2009.0388

48. Roter, D. and Larson, S. (2002) The Roter Interaction Analysis System (RIAS): Utility and Flexibility for Analysis of Medical Interactions. Patient Education and Counseling, 46, 243-251.http://dx.doi.org/10.1016/S0738-3991(02)00012-5

49. Salih, S.A., Wootton, R., Beller, E. and Gray, L. (2007) The Validity of Video Clips in the Diagnosis of Gait Disorder. Journal of Telemedicine and Telecare, 13, 333-336. http://dx.doi.org/10.1258/135763307782215406

50. Gilbert, D.A. and Hayes, E. (2009) Communication and Outcomes of Visits between Older Patients and Nurse Practitioners. Nursing Research, 58, 283-293. http://dx.doi.org/10.1097/NNR.0b013e3181ac1413

51. Hayes, E. (2006) Promoting Nurse Practitioner Practice through Research: Opportunities, Challenges, and Lessons. Journal of the American Academy of Nurse Practitioners, 18, 180-186.http://dx.doi.org/10.1111/j.1745-7599.2006.00118.x

52. Riley, R.G. and Manias, E. (2004) The Uses of Photography in Clinical Nursing Practice and Research: A Literature Review. Journal of Advanced Nursing, 48, 397-405. http://dx.doi.org/10.1111/j.1365-2648.2004.03208.x

53. Coleman, T. (2000) Using Video-Recorded Consultations for Research in Primary Care: Advantages and Limitations. Family Practice, 17, 422-427. http://dx.doi.org/10.1093/fampra/17.5.422

54. Pearce, C., Arnold, M., Phillips, C. and Dwan, K. (2010) Methodological Considerations of Digital Video Observation: beyond Conversation Analysis. International Journal of Multiple Research Approaches, 4, 90-99.http://dx.doi.org/10.5172/mra.2010.4.2.090

55. Ritchie, J. and Spencer, L. (1993) Qualitative Data Analysis for Applied Policy Research. In: Bryman, A. and Burgess, R., Eds., Analysing Qualitative Data, Routledge, London, 173-194.

56. Pope, C., Ziebland, S. and Mays, N. (2000) Qualitative Research in Health Care. BMJ, 320, 114-116.http://dx.doi.org/10.1136/bmj.320.7227.114

57. Sharp, K. (1998) The Case for Case Studies in Nursing Research: The Problem of Generalization. Journal of Advanced Nursing, 27, 785-789. http://dx.doi.org/10.1046/j.1365-2648.1998.00604.x