'ThinkCancer!' - Randomised feasibility trial of a novel practice-based early cancer diagnosis intervention

BACKGROUND

UK cancer deaths remain high; primary care is key for earlier cancer diagnosis as half of avoidable delays occur here. Improvement is possible through lower referral thresholds, better guideline adherence, and better safety netting systems. Few interventions target whole practice teams. We developed a novel whole practice team intervention to address this.

AIM

To test the feasibility and acceptability of a novel, complex behavioural intervention 'ThinkCancer!' for assessment in a subsequent Phase III trial.

DESIGN & SETTING

Pragmatic, superiority pilot RCT with an embedded process evaluation and feasibility economic analysis in Welsh general practices.

METHOD

Clinical outcome data were collected from practices (the unit of randomisation). Practice characteristics and cancer safety netting systems were assessed. Individual practice staff completed evaluation and feedback forms, and qualitative interviews. The intervention was adapted and refined.

RESULTS

Trial recruitment and workshop deliveries took place between March 2020 to May 2021. Trial progression criteria for recruitment, intervention fidelity and routine data collection were met. Staff-level fidelity, retention and individual level data collection processes were reviewed and amended. Interviews highlighted positive participant views on all aspects of the intervention. All practices set out to liberalise referral thresholds appropriately, implement guidelines, and address safety netting plans in detail.

CONCLUSION

'ThinkCancer!' appears feasible and acceptable; the new iteration of the workshops was completed, and the Phase III trial has been funded to assess the effectiveness and cost effectiveness of this novel professional behaviour change intervention. Delivery at scale to multiple practices will likely improve fidelity and reach.

Earlier cancer diagnosis in primary care: a feasibility economic analysis of ThinkCancer!

BACKGROUND

UK cancer survival rates are much lower compared with other high-income countries. In primary care, there are opportunities for GPs and other healthcare professionals to act more quickly in response to presented symptoms that might represent cancer. ThinkCancer! is a complex behaviour change intervention aimed at primary care practice teams to improve the timely diagnosis of cancer.

AIM

To explore the costs of delivering the ThinkCancer! intervention to expedite cancer diagnosis in primary care.

DESIGN & SETTING

Feasibility economic analysis using a micro-costing approach, which was undertaken in 19 general practices in Wales, UK.

METHOD

From an NHS perspective, micro-costing methodology was used to determine whether it was feasible to gather sufficient economic data to cost the ThinkCancer!

INTERVENTION

Owing to the COVID-19 pandemic, ThinkCancer! was mainly delivered remotely online in a digital format. Budget impact analysis (BIA) and sensitivity analysis were conducted to explore the costs of face-to-face delivery of the ThinkCancer! intervention as intended pre-COVID-19.

RESULTS

The total costs of delivering the ThinkCancer! intervention across 19 general practices in Wales was £25 030, with an average cost per practice of £1317 (standard deviation [SD]: 578.2). Findings from the BIA indicated a total cost of £34 630 for face-to-face delivery.

CONCLUSION

Data collection methods were successful in gathering sufficient health economics data to cost the ThinkCancer!

INTERVENTION

Results of this feasibility study will be used to inform a future definitive economic evaluation alongside a pragmatic randomised controlled trial (RCT).

The intricacy of interactions: qualitative exploration of preferences and perceptions of advance care planning among healthcare professionals, patients and those close to them

Objectives:

Advance care planning (ACP) is a way of documenting preferences in case of a change or decline in health via verbal discussion and may include a written document. ACP relates not only to treatment preferences but to all aspects of future care such as place of death, plans for dependents and spiritual beliefs. Research has shown that ACP can have a positive impact but needs further understanding to enhance communication and increase uptake. This article focusses on the importance and intricacy of interactions and why a preference-based approach may be beneficial for the future.

Methods:

This article reports two separate, but related, pieces of qualitative research. First, focus groups to evaluate perspectives of healthcare professionals (HCPs) following their attendance at a North Wales ACP training workshop. The second study comprised interviews exploring the views of patients, those close to them and HCPs regarding ACP.

Results:

ACP interactions are complex and intricate. There is an association with end of life rather than changes in health among patients and HCPs often view discussions as akin to ‘breaking bad news’. Good communication between patients, loved ones and HCPs is essential to reduce distress and ensure preferences are understood. Trust between patients and HCPs is of high importance and often a patient will have a preferred HCP who they feel comfortable discussing ACP with.

Conclusion:

A preference-based approach to ACP has potential to widen participation in ACP, relieve anxiety and ease burden for patients and carers. Further research is needed to identify ways to increase inclusivity.

Protocol for a feasibility study of a cancer symptom awareness campaign to support the rapid diagnostic centre referral pathway in a socioeconomically deprived area: Targeted Intensive Community-based campaign To Optimise Cancer awareness (TIC-TOC)

INTRODUCTION

Rapid diagnostic centres (RDCs) are being implemented across the UK to accelerate the assessment of vague suspected cancer symptoms. Targeted behavioural interventions are needed to augment RDCs that serve socioeconomically deprived populations who are disproportionately affected by cancer, have lower cancer symptom awareness and are less likely to seek help for cancer symptoms. The aim of this study is to assess the feasibility and acceptability of delivering and evaluating a community-based vague cancer symptom awareness intervention in an area of high socioeconomic deprivation.

METHODS AND ANALYSIS

Intervention materials and messages were coproduced with local stakeholders in Cwm Taf Morgannwg, Wales. Cancer champions will be trained to deliver intervention messages and distribute intervention materials using broadcast media (eg, local radio), printed media (eg, branded pharmacy bags, posters, leaflets), social media (eg, Facebook) and attending local community events. A cross-sectional questionnaire will include self-reported patient interval (time between noticing symptoms to contacting the general practitioner), cancer symptom recognition, cancer beliefs and barriers to presentation, awareness of campaign messages, healthcare resource use, generic quality of life and individual and area-level deprivation indicators. Consent rates and proportion of missing data for patient questionnaires (n=189) attending RDCs will be measured. Qualitative interviews and focus groups will assess intervention acceptability and barriers/facilitators to delivery.

ETHICS AND DISSEMINATION

Ethical approval for this study was given by the London-West London & GTAC Research Ethics (21/LO/0402). This project will inform a potential future controlled study to assess intervention effectiveness in reducing the patient interval for vague cancer symptoms. The results will be critical to informing national policy and practice regarding behavioural interventions to support RDCs in highly deprived populations.

The juxtaposition of the natural and the medical perspectives in noisy breathing at the end of life

BACKGROUND

Noisy breathing is common at the end of life. Management of noisy breathing aims to reduce the noise via repositioning the person, suctioning the person's airways and using antimuscarinic drugs. Dying people are generally thought not to be distressed by noisy breathing at the end of life, but the noise may distress others. There is doubt on whether antimuscarinic drugs are any more effective than a placebo for noisy breathing. However, antimuscarinics are still commonly administered to people at the end of life.

AIM

To illuminate reasons behind decision making and noisy breathing at the end of life.

METHODS

Semi-structured interviews and 'self-recorded brief accounts' with healthcare professionals.

FINDINGS

Noisy breathing at the end of life is viewed as both a natural and a medical phenomenon. However, while most participants in the interviews thought that antimuscarinics were uneffective, the prescription and administration of antimuscarinics were embedded within professional culture.

CONCLUSION

Managing noisy breathing is a complex issue that incorporates natural and medical viewpoints and has a long-standing culture of practice. Research should aim to determine best practice and reduce a person's distress at the end of life.

Promoting physical activity and physical function in people with long-term conditions in primary care: the Function First realist synthesis with co-design

Background

As people age and accumulate long-term conditions, their physical activity and physical function declines, resulting in disability and loss of independence. Primary care is well placed to empower individuals and communities to reduce this decline; however, the best approach is uncertain.

Objectives

To develop a programme theory to explain the mechanisms through which interventions improve physical activity and physical function in people with long-term conditions in different primary care contexts, and to co-design a prototype intervention.

Data sources

Systematic literature searches of relevant databases with forwards and backwards citation tracking, grey literature searches and further purposive searches were conducted. Qualitative data were collected through workshops and interviews.

Design

Realist evidence synthesis and co-design for primary care service innovation.

Setting

Primary care in Wales and England.

Participants

Stakeholders included people with long-term conditions, primary care professionals, people working in relevant community roles and researchers.

Methods

The realist evidence synthesis combined evidence from varied sources of literature with the views, experiences and ideas of stakeholders. The resulting context, mechanism and outcome statements informed three co-design workshops and a knowledge mobilisation workshop for primary care service innovation.

Results

Five context, mechanism and outcome statements were developed. (1) Improving physical activity and function is not prioritised in primary care (context). If the practice team culture is aligned to the elements of physical literacy (mechanism), then physical activity promotion will become routine and embedded in usual care (outcome). (2) Physical activity promotion is inconsistent and unco-ordinated (context). If specific resources are allocated to physical activity promotion (in combination with a supportive practice culture) (mechanism), then this will improve opportunities to change behaviour (outcome). (3) People with long-term conditions have varying levels of physical function and physical activity, varying attitudes to physical activity and differing access to local resources that enable physical activity (context). If physical activity promotion is adapted to individual needs, preferences and local resources (mechanism), then this will facilitate a sustained improvement in physical activity (outcome). (4) Many primary care practice staff lack the knowledge and confidence to promote physical activity (context). If staff develop an improved sense of capability through education and training (mechanism), then they will increase their engagement with physical activity promotion (outcome). (5) If a programme is credible with patients and professionals (context), then trust and confidence in the programme will develop (mechanism) and more patients and professionals will engage with the programme (outcome). A prototype multicomponent intervention was developed. This consisted of resources to nurture a culture of physical literacy, materials to develop the role of a credible professional who can promote physical activity using a directory of local opportunities and resources to assist with individual behaviour change.

Limitations

Realist synthesis and co-design is about what works in which contexts, so these resources and practice implications will need to be modified for different primary care contexts.

Conclusions

We developed a programme theory to explain how physical activity could be promoted in primary care in people with long-term conditions, which informed a prototype intervention.

Future work

A future research programme could further develop the prototype multicomponent intervention and assess its acceptability in practice alongside existing schemes before it is tested in a feasibility study to inform a future randomised controlled trial.

Study registration

This study is registered as PROSPERO CRD42018103027.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 9, No. 16. See the NIHR Journals Library website for further project information.

'Function First': how to promote physical activity and physical function in people with long-term conditions managed in primary care? A study combining realist and co-design methods

OBJECTIVES

To develop a taxonomy of interventions and a programme theory explaining how interventions improve physical activity and function in people with long-term conditions managed in primary care. To co-design a prototype intervention informed by the programme theory.

DESIGN

Realist synthesis combining evidence from a wide range of rich and relevant literature with stakeholder views. Resulting context, mechanism and outcome statements informed co-design and knowledge mobilisation workshops with stakeholders to develop a primary care service innovation.

RESULTS

A taxonomy was produced, including 13 categories of physical activity interventions for people with long-term conditions.

ABRIDGED REALIST PROGRAMME THEORY

Routinely addressing physical activity within consultations is dependent on a reinforcing practice culture, and targeted resources, with better coordination, will generate more opportunities to address low physical activity. The adaptation of physical activity promotion to individual needs and preferences of people with long-term conditions helps affect positive patient behaviour change. Training can improve knowledge, confidence and capability of practice staff to better promote physical activity. Engagement in any physical activity promotion programme will depend on the degree to which it makes sense to patients and professions, and is seen as trustworthy.

CO-DESIGN

The programme theory informed the co-design of a prototype intervention to: improve physical literacy among practice staff; describe/develop the role of a physical activity advisor who can encourage the use of local opportunities to be more active; and provide materials to support behaviour change.

CONCLUSIONS

Previous physical activity interventions in primary care have had limited effect. This may be because they have only partially addressed factors emerging in our programme theory. The co-designed prototype intervention aims to address all elements of this emergent theory, but needs further development and consideration alongside current schemes and contexts (including implications relevant to COVID-19), and testing in a future study. The integration of realist and co-design methods strengthened this study.

Protocol for a feasibility study incorporating a randomised pilot trial with an embedded process evaluation and feasibility economic analysis of ThinkCancer!: a primary care intervention to expedite cancer diagnosis in Wales

BACKGROUND

Compared to the rest of Europe, the UK has relatively poor cancer outcomes, with late diagnosis and a slow referral process being major contributors. General practitioners (GPs) are often faced with patients presenting with a multitude of non-specific symptoms that could be cancer. Safety netting can be used to manage diagnostic uncertainty by ensuring patients with vague symptoms are appropriately monitored, which is now even more crucial due to the ongoing COVID-19 pandemic and its major impact on cancer referrals. The ThinkCancer! workshop is an educational behaviour change intervention aimed at the whole general practice team, designed to improve primary care approaches to ensure timely diagnosis of cancer. The workshop will consist of teaching and awareness sessions, the appointment of a Safety Netting Champion and the development of a bespoke Safety Netting Plan and has been adapted so it can be delivered remotely. This study aims to assess the feasibility of the ThinkCancer! intervention for a future definitive randomised controlled trial.

METHODS

The ThinkCancer! study is a randomised, multisite feasibility trial, with an embedded process evaluation and feasibility economic analysis. Twenty-three to 30 general practices will be recruited across Wales, randomised in a ratio of 2:1 of intervention versus control who will follow usual care. The workshop will be delivered by a GP educator and will be adapted iteratively throughout the trial period. Baseline practice characteristics will be collected via questionnaire. We will also collect primary care intervals (PCI), 2-week wait (2WW) referral rates, conversion rates and detection rates at baseline and 6 months post-randomisation. Participant feedback, researcher reflections and economic costings will be collected following each workshop. A process evaluation will assess implementation using an adapted Normalisation Measure Development (NoMAD) questionnaire and qualitative interviews. An economic feasibility analysis will inform a future economic evaluation.

DISCUSSION

This study will allow us to test and further develop a novel evidenced-based complex intervention aimed at general practice teams to expedite the diagnosis of cancer in primary care. The results from this study will inform the future design of a full-scale definitive phase III trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04823559 .

Carer administration of as-needed subcutaneous medication for breakthrough symptoms in people dying at home: the CARiAD feasibility RCT

BACKGROUND

Most people who are dying want to be cared for at home, but only half of them achieve this. The likelihood of a home death often depends on the availability of able and willing lay carers. When people who are dying are unable to take oral medication, injectable medication is used. When top-up medication is required, a health-care professional travels to the dying person's home, which may delay symptom relief. The administration of subcutaneous medication by lay carers, although not widespread UK practice, has proven to be key in achieving better symptom control for those dying at home in other countries.

OBJECTIVES

To determine if carer administration of as-needed subcutaneous medication for common breakthrough symptoms in people dying at home is feasible and acceptable in the UK, and if it would be feasible to test this intervention in a future definitive randomised controlled trial.

DESIGN

We conducted a two-arm, parallel-group, individually randomised, open pilot trial of the intervention versus usual care, with a 1 : 1 allocation ratio, using convergent mixed methods.

SETTING

Home-based care without 24/7 paid care provision, in three UK sites.

PARTICIPANTS

Participants were dyads of adult patients and carers: patients in the last weeks of their life who wished to die at home and lay carers who were willing to be trained to give subcutaneous medication. Strict risk assessment criteria needed to be met before approach, including known history of substance abuse or carer ability to be trained to competency.

INTERVENTION

Intervention-group carers received training by local nurses using a manualised training package.

MAIN OUTCOME MEASURES

Quantitative data were collected at baseline and 6-8 weeks post bereavement and via carer diaries. Interviews with carers and health-care professionals explored attitudes to, experiences of and preferences for giving subcutaneous medication and experience of trial processes. The main outcomes of interest were feasibility, acceptability, recruitment rates, attrition and selection of the most appropriate outcome measures.

RESULTS

In total, 40 out of 101 eligible dyads were recruited (39.6%), which met the feasibility criterion of recruiting > 30% of eligible dyads. The expected recruitment target (≈50 dyads) was not reached, as fewer than expected participants were identified. Although the overall retention rate was 55% (22/40), this was substantially unbalanced [30% (6/20) usual care and 80% (16/20) intervention]. The feasibility criterion of > 40% retention was, therefore, considered not met. A total of 12 carers (intervention, n = 10; usual care, n = 2) and 20 health-care professionals were interviewed. The intervention was considered acceptable, feasible and safe in the small study population. The context of the feasibility study was not ideal, as district nurses were seriously overstretched and unfamiliar with research methods. A disparity in readiness to consider the intervention was demonstrated between carers and health-care professionals. Findings showed that there were methodological and ethics issues pertaining to researching last days of life care.

CONCLUSION

The success of a future definitive trial is uncertain because of equivocal results in the progression criteria, particularly poor recruitment overall and a low retention rate in the usual-care group. Future work regarding the intervention should include understanding the context of UK areas where this has been adopted, ascertaining wider public views and exploring health-care professional views on burden and risk in the NHS context. There should be consideration of the need for national policy and of the most appropriate quantitative outcome measures to use. This will help to ascertain if there are unanswered questions to be studied in a trial.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN11211024.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 25. See the NIHR Journals Library website for further project information.

'Function First-Be Active, Stay Independent'-promoting physical activity and physical function in people with long-term conditions by primary care: a protocol for a realist synthesis with embedded co-production and co-design

INTRODUCTION

People with long-term conditions typically have reduced physical functioning, are less physically active and therefore become less able to live independently and do the things they enjoy. However, assessment and promotion of physical function and physical activity is not part of routine management in primary care. This project aims to develop evidence-based recommendations about how primary care can best help people to become more physically active in order to maintain and improve their physical function, thus promoting independence.

METHODS AND ANALYSIS

This study takes a realist synthesis approach, following RAMESES guidance, with embedded co-production and co-design. Stage 1 will develop initial programme theories about physical activity and physical function for people with long-term conditions, based on a review of the scientific and grey literature, and two multisector stakeholder workshops using LEGO® SERIOUS PLAY®. Stage 2 will involve focused literature searching, data extraction and synthesis to provide evidence to support or refute the initial programme theories. Searches for evidence will focus on physical activity interventions involving the assessment of physical function which are relevant to primary care. We will describe 'what works', 'for whom' and 'in what circumstances' and develop conjectured programme theories using context, mechanism and outcome configurations. Stage 3 will test and refine these theories through individual stakeholder interviews. The resulting theory-driven recommendations will feed into Stage 4 which will involve three sequential co-design stakeholder workshops in which practical ideas for service innovation in primary care will be developed.

ETHICS AND DISSEMINATION

Healthcare and Medical Sciences Academic Ethics Committee (Reference 2018-16308) and NHS Wales Research Ethics Committee 5 approval (References 256 729 and 262726) have been obtained. A knowledge mobilisation event will address issues relevant to wider implementation of the intervention and study findings. Findings will be disseminated through peer-reviewed journal publications, conference presentations and formal and informal reports.

PROSPERO REGISTRATION NUMBER

CRD42018103027.

The development of the Primary Care Clusters Multidimensional Assessment (PCCMA): A mixed-methods study

A strong primary care (PC) system is essential for an efficient and high-quality healthcare service. Many countries have adopted a model of PC that encourages different healthcare providers to work together, at scale, in multidisciplinary/multiagency teams (PC clusters). The aim of the present work was to develop a quantitative instrument for the systematic and comprehensive assessment of PC clusters. This was a non-experimental, mixed-methods study grouping four work packages (WP), and involving PC cluster leads and a wide range of key stakeholders from across Wales. Interviews with 22 PC cluster leads (34 %) investigated the clusters' functioning (WP1). A systematic review identified relevant PC assessment frameworks and instruments (WP2). An expert group reviewed the evidence and drafted the new assessment tool, further evaluated and amended in two stakeholder workshops (WP3). Thirty-eight cluster leads (62 %) completed the newly developed online assessment (WP4). The final instrument consisted of 53 indicators, across 11 systemic dimensions of PC and produced a comprehensive assessment of the functioning of PC clusters in Wales. This rigorous early development of an innovative instrument to evaluate PC at a scaled-up (cluster) level (particularly in the format of a 360-degree assessment) can inform healthcare policy decisions regarding the expansion and ongoing adjustment of the model in response to local needs and challenges.

Percutaneous venting gastrostomy/gastrojejunostomy for malignant bowel obstruction: a qualitative study

OBJECTIVE

Malignant bowel obstruction (MBO) is a complication of advanced malignancy and is associated with a short prognosis. MBO can infrequently be reversed by surgery or stenting. The focus of treatment is usually symptomatic management, of which percutaneous venting gastrostomy/gastrojejunostomy (PVG) is one consideration. There is little data considering the impact of PVG on quality of life; we therefore aimed to explore this.

METHODS

We identified patients with a PVG inserted for MBO and those who consented to participate were interviewed. The interviews were audio recorded, transcribed and analysed using Framework. Alongside patient interviews, a data collection tool was designed and used to record patient demographics and medical information, enabling us to contextualise individual patients' experiences.

RESULTS

11 patients were interviewed and 10 patients' data were analysed (1 patient withdrew). No patients regretted having a PVG and many benefitted symptomatically and psychosocially. Challenges encountered included practical issues, pain and PVG tube complications.

CONCLUSIONS

The analysis provided a detailed insight into the impact of PVG insertion and demonstrated that each patient's experience is shaped by a complex interplay of individual factors, thereby highlighting the need to improve referral criteria and individualise patient selection. Other service improvements include enhancing information provision for patients and training for healthcare professionals, thus aiming to mitigate the challenges experienced. Our study is the first in-depth exploration of patients' experiences of PVG at a tertiary cancer centre. Ensuring that the insights from this study are fed back to guide future service provision is critical in enhancing future patient experiences.

Engaging high-risk groups in early lung cancer diagnosis: a qualitative study of symptom presentation and intervention preferences among the UK's most deprived communities

OBJECTIVES

People at high-risk for lung cancer-current/former smokers, aged 40+ years, with serious lung comorbidity (ie, chronic obstructive pulmonary disease) and living in highly deprived areas-are more likely to delay symptom presentation. This qualitative study aimed to understand the influences on early presentation with lung cancer symptoms in high-risk individuals and intervention preferences.

METHODS

Semi-structured qualitative interviews with 37 high-risk individuals (without a cancer diagnosis), identified through seven GP practices in socioeconomically deprived areas of England, Scotland and Wales (most deprived 20%). A symptom attribution task was used to explore lung symptom perception and help seeking, developed using Leventhal's Common Sense Model. Four focus groups with 16 high-risk individuals and 12 local stakeholders (healthcare professionals and community partners) were conducted to explore preferences for an intervention to promote early lung cancer symptom presentation. Data were synthesised using Framework analysis.

RESULTS

Individual and area level indicators of deprivation confirmed that interview participants were highly deprived. Interviews. Preoccupation with managing 'treatable' short-term conditions (chest infections), led to avoidance of acting on 'inevitable and incurable' long-term conditions (lung cancer). Feeling judged and unworthy of medical help because of their perceived social standing or lifestyle deterred medical help seeking, particularly when difficult life circumstances and traumatic events led to tobacco and alcohol addiction. Focus groups. Participants recommended multifaceted interventions in community venues, with information about lung cancer symptoms and the benefits of early diagnosis, led by a trained and non-judgemental facilitator.

CONCLUSIONS

This study was novel in engaging a high-risk population to gain an in-depth understanding of the broader contextual influences on lung cancer symptom presentation. Perceived lack of health service entitlement and complex lives facilitated avoidance of recognising and presenting with lung cancer symptoms. Community-based interventions have the potential to empower disadvantaged populations to seek medical help for lung symptoms.

CARer-ADministration of as-needed subcutaneous medication for breakthrough symptoms in homebased dying patients (CARiAD): study protocol for a UK-based open randomised pilot trial

Background

While the majority of seriously ill people wish to die at home, only half achieve this. The likelihood of someone dying at home often depends on the availability of able and willing lay carers to support them.

Dying people are usually unable to take oral medication. When top-up symptom relief medication is required, a clinician travels to the home to administer injectable medication, with attendant delays. The administration of subcutaneous injections by lay carers, though not widespread practice in the UK, has proven key in achieving home deaths in other countries.

Our aim is to determine if carer-administration of as-needed subcutaneous medication for four frequent breakthrough symptoms (pain, nausea, restlessness and noisy breathing) in home-based dying patients is feasible and acceptable in the UK.

Methods

This paper describes a randomised pilot trial across three UK sites, with an embedded qualitative study. Dyads of adult patients/carers are eligible, where patients are in the last weeks of life and wish to die at home, and lay carers who are willing to be trained to give subcutaneous medication. Dyads who do not meet strict risk assessment criteria (including known history of substance abuse or carer ability to be trained to competency) will not be approached. Carers in the intervention arm will receive a manualised training package delivered by their local nursing team. Dyads in the control arm will receive usual care. The main outcomes of interest are feasibility, acceptability, recruitment rates, attrition and selection of the most appropriate outcome measures. Interviews with carers and healthcare professionals will explore attitudes to, experiences of and preferences for giving subcutaneous medication and experience of trial processes. The study has obtained full ethical approval.

Discussion

This study will rehearse the procedures and logistics which will be undertaken in a future definitive randomised controlled trial and will inform the design of such a study. Findings will illuminate methodological and ethical issues pertaining to researching last days of life care.

The study is funded by the National Institute for Health Research (Health Technology Assessment [HTA] project 15/10/37).

Trial registration

ISRCTN, ISRCTN 11211024. Registered on 27 September 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3179-9) contains supplementary material, which is available to authorized users.

A lifestyle management programme focused on exercise, diet and physiotherapy support for patients with hip or knee osteoarthritis and a body mass index over 35: A qualitative study

The Lifestyle Management Programme (LMP) is an exercise and weight management programme with physiotherapy support for people with hip or knee osteoarthritis (OA) and a body mass index (BMI) over 35. This qualitative study explored views and experiences of the LMP among patients and professionals, and offers insight for future programmes. Five referring clinicians and six delivering professionals participated in focus groups. Three referring GPs and nine patients who attended the LMP took part in semi-structured interviews. Topics included: referral, reasons for taking up and continuing the programme or not, and experiences and outcomes. Framework method was used to analyse the qualitative data. Overall, patients and professionals valued the multidisciplinary nature of the LMP. However, professionals explained feeling guilty about delaying patients on the orthopaedic waiting list and believed that the programme should be redirected to those with less severe OA and a lower BMI. Referring clinicians differed in their interpretation of the referral criteria and expressed varying levels of autonomy when making referrals. Patients referred after a consultation with their general practitioner appeared to be more satisfied with the referral process. Patients were also encouraged by the opportunity to improve health, their likelihood of surgery and social benefits. However, patients were discouraged by inconvenience, cost, lack of readiness to change and embarrassment. In conclusion, shared decision-making about lifestyle management without delaying orthopaedic opinion is preferable, and more psychological support may increase participation. Importantly, the programme may be better focused on rehabilitation for patients with a lower BMI and less severe symptoms.

Trial of personalised care after treatment-Prostate cancer: A randomised feasibility trial of a nurse-led psycho-educational intervention

OBJECTIVE

The present parallel randomised control trial evaluated the feasibility of a nurse-led psycho-educational intervention aimed at improving the self-management of prostate cancer survivors.

METHODS

We identified 305 eligible patients from a district general hospital, diagnosed 9-48 months previously, who completed radical treatment, or were monitored clinically (ineligible for treatment). Ninety-five patients were recruited by blinded selection and randomised to Intervention (N = 48) and Control (N = 47) groups. Participant allocation was revealed to patients and researchers after recruitment was completed. For 36 weeks, participants received augmented usual care (Control) or augmented usual care and additional nurse support (Intervention) provided in two community hospitals and a university clinic, or by telephone.

RESULTS

Data from 91 participants (Intervention, N = 45; Control, N = 46) were analysed. All feasibility metrics met predefined targets: recruitment rate (31.15%; 95% CI: 25.95%-36.35%), attrition rate (9.47%; 95% CI: 3.58%-15.36%) and outcome measures completion rates (77%-92%). Forty-five patients received the intervention, with no adverse events. The Extended Prostate Cancer Index Composite can inform the minimum sample size for a future effectiveness trial. The net intervention cost was £317 per patient.

CONCLUSIONS

The results supported the feasibility and acceptability of the intervention, suggesting that it should be evaluated in a fully powered trial to assess its effectiveness and cost-effectiveness.

Development of an intervention to expedite cancer diagnosis through primary care: a protocol

BACKGROUND

GPs can play an important role in achieving earlier cancer diagnosis to improve patient outcomes, for example through prompt use of the urgent suspected cancer referral pathway. Barriers to early diagnosis include individual practitioner variation in knowledge, attitudes, beliefs, professional expectations, and norms.

AIM

This programme of work (Wales Interventions and Cancer Knowledge about Early Diagnosis [WICKED]) will develop a behaviour change intervention to expedite diagnosis through primary care and contribute to improved cancer outcomes.

DESIGN & SETTING

Non-experimental mixed-method study with GPs and primary care practice teams from Wales.

METHOD

Four work packages will inform the development of the behaviour change intervention. Work package 1 will identify relevant evidence-based interventions (systematic review of reviews) and will determine why interventions do or do not work, for whom, and in what circumstances (realist review). Work package 2 will assess cancer knowledge, attitudes, and behaviour of GPs, as well as primary care teams' perspectives on cancer referral and investigation (GP survey, discrete choice experiment [DCE], interviews, and focus groups). Work package 3 will synthesise findings from earlier work packages using the behaviour change wheel as an overarching theoretical framework to guide intervention development. Work package 4 will test the feasibility and acceptability of the intervention, and determine methods for measuring costs and effects of subsequent behaviour change in a randomised feasibility trial.

RESULTS

The findings will inform the design of a future effectiveness trial, with concurrent economic evaluation, aimed at earlier diagnosis.

CONCLUSION

This comprehensive, evidence-based programme will develop a complex GP behaviour change intervention to expedite the diagnosis of symptomatic cancer, and may be applicable to countries with similar healthcare systems.

Talking about human papillomavirus and cancer: development of consultation guides through lay and professional stakeholder coproduction using qualitative, quantitative and secondary data

BACKGROUND

High-risk human papillomaviruses (HPVs) cause all cervical cancer and the majority of vulvar, vaginal, anal, penile and oropharyngeal cancers. Although HPV is the most common sexually transmitted infection, public awareness of this is poor. In addition, many clinicians lack adequate knowledge or confidence to discuss sexual transmission and related sensitive issues. Complex science needs to be communicated in a clear, digestible, honest and salient way. Therefore, the aim of this study was to coproduce with patients who have cancer appropriate resources to guide these highly sensitive and difficult consultations.

METHODS

A matrix of evidence developed from a variety of sources, including a systematic review and telephone interviews with clinicians, supported the production of a draft list of approximately 100 potential educational messages. These were refined in face-to-face patient interviews using card-sorting techniques, and tested in cognitive debrief interviews to produce a ‘fast and frugal’ knowledge tool.

RESULTS

We developed three versions of a consultation guide, each comprising a clinician guidance sheet and patient information leaflet for gynaecological (cervical, vaginal, vulvar), anal or oropharyngeal cancers. That cancer could be caused by a sexually transmitted virus acquired many years previously was surprising to many and shocking to a few patients. However, they found the information clear, helpful and reassuring. Clinicians acknowledged a lack of confidence in explaining HPV, welcomed the clinician guidance sheets and considered printed information for patients particularly useful.

CONCLUSION

Because of the ‘shock factor’, clinicians will need to approach the discussion of HPV with sensitivity and take individual needs and preferences into account, but we provide a novel, rigorously developed and tested resource which should have broad applicability in the UK National Health Service and other health systems.

Dying at home of cancer: whose needs are being met? The experience of family carers and healthcare professionals (a multiperspective qualitative study)

Objectives

Supporting patients to die in the place of their choosing is an important aspect of end of life care. Our study set out to answer the question: ‘How does the home environment influence perceptions of quality of death, and the experience of caring for the dying at home, for family carers and healthcare professionals (HCPs)?

Methods

A qualitative approach, using multiperspective interviews with bereaved family carers (n=15) and a nominated HCP (n=13) ensured depth of insight gained into supporting a home death. The semistructured interviews were audio recorded, transcribed verbatim and analysed using Framework.

Results

We found that the home environment enabled normality, a sense of control and individualised care which family carers often perceived as contributing towards a good death. However, the home environment created challenges for both family carers and HCPs, due to the differing and at times conflicting needs of the dying person and their family carers.

Conclusions

We have shed light on the complexity of balancing the demands and the satisfaction of caring for someone dying at home. The ability to manage these conflicting needs influenced whether carers perceived the home setting as the best place for the person to have received care in their last days of life.

Perceptions of risk as a barrier to the use of telemedicine

There is little published information about the perceptions of risk in the use of telemedicine services. The present study drew on data from two separate research projects. The data comprised interviews with health professionals, technologists, managers and patient advocates involved in telemedicine. The interviews were recorded, transcribed and analysed thematically. Key themes included the need to balance risks against potential benefits and the suggestion that risk was a method of resisting change. Another theme was trust, both in health professionals and the technology itself. It appears that risk management issues may be an important barrier to the implementation of telemedicine services.

Talking about human papillomavirus and cancer: protocol for a patient-centred study to develop scripted consultations

INTRODUCTION

Persistent infection with sexually transmitted, high-risk human papillomavirus (HPV) types is the cause of all cervical cancers and some anogenital and oropharyngeal cancers. HPV is an extremely common asymptomatic infection but little known and poorly understood by the public. Patients with HPV-related cancers have new and challenging information needs due to the complex natural history of HPV and the stigma of sexual transmission. They may ask questions that are outside the remit of the traditional cancer consultation, and there is a lack of guidance on how to counsel them. This study aims to fulfil that need by developing and testing cancer site-specific scripted consultations.

METHODS AND ANALYSIS

A synthesis of findings generated from previous work, a systematic review of information-based interventions for patients with HPV-related cancers, and interviews with cancer clinicians will provide the evidence base underpinning provisional messages. These will be explored in three phases of face-to-face interviews with 75-90 purposively selected patients recruited in cancer clinics to: (1) select and prioritise the most salient messages, (2) phrase the messages appropriately in plain English and, (3) test their acceptability and usefulness. Phases 1 and 2 will draw on card-sorting methods used in website design. In phase three, we will create cancer site-specific versions of the script and test them using cognitive interviewing techniques.

ETHICS AND DISSEMINATION

The study has received ethical approval. Findings will be published in a peer-reviewed journal. The final product will be cancer-specific scripted consultations, most likely in the form of a two-sided information sheet with the most important messages to be conveyed in a consultation on one side, and frequently asked questions for later reading on the reverse. However, they will also be appropriate and readily adaptable to web-based uses.

A pilot randomised controlled trial of personalised care after treatment for prostate cancer (TOPCAT-P): nurse-led holistic-needs assessment and individualised psychoeducational intervention: study protocol

INTRODUCTION

Prostate cancer is common and the incidence is increasing, but more men are living longer after diagnosis, and die with their disease rather than of it. Nonetheless, specific and substantial physical, sexual, emotional and mental health problems often lead to a poor quality of life. Urology services increasingly struggle to cope with the demands of follow-up care, and primary care is likely to play the central role in long-term follow-up. The present phase II trial will evaluate the feasibility and acceptability of a nurse-led, person-centred psychoeducational intervention, delivered in community or primary care settings.

METHODS AND ANALYSIS

Prostate cancer survivors diagnosed in the past 9-48 months and currently biochemically stable will be identified from hospital records by their treating clinician. Eligible men would have either completed radical treatment, or would be followed up with prostate specific antigen monitoring and symptom reporting. We will recruit 120 patients who will be randomised to receive either an augmented form of usual care, or an additional nurse-led intervention for a period of 36 weeks. Following the health policy in Wales, the intervention is offered by a key worker, is promoting prudent healthcare and is using a holistic needs assessment. Outcome measures will assess physical symptoms, psychological well-being, confidence in managing own health and quality of life. Healthcare service use will be measured over 36 weeks. Feedback interviews with patients and clinicians will further inform the acceptability of the intervention. Recruitment, attrition, questionnaire completion rates and outcome measures variability will be assessed, and results will inform the design of a future phase III trial and accompanying economic evaluation.

ETHICS AND DISSEMINATION

Ethics approval was granted by Bangor University and North Wales REC (13/WA/0291). Results will be reported in peer-reviewed publications, at scientific conferences, and directly through national cancer and primary care networks.

TRIAL REGISTRATION NUMBER

ISRCTN 34516019.

‘Carrying on the way we are is becoming shambolic’ – An interview study with prostate cancer specialists about their usual practice of follow-up

Aim:

This study aims to clarify what practice for the follow-up of prostate cancer is occurring at present and to explain the reasons behind any variation.

Background:

Prostate cancer has been increasing in incidence in the UK for several years. It has been suggested that men with prostate cancer could be better managed, and that some aspects of care are duplicated by primary and secondary care professionals.

Methods:

This study aimed to interview the prostate cancer specialists identified as working within the district general hospitals of a large health board. The interviews used a qualitative semi-structured approach. Analysis was performed using The Framework method.

Findings:

Current practice for the follow-up of prostate cancer is variable both within and between hospitals. Patients are followed up in secondary care for longer than National Institute for Health and Care Excellence (NICE) recommends due to a lack of trust of general practitioners’ management. This inevitably impacts upon waiting lists, and many patients’ appointments are long overdue. A remote prostate-specific antigen (PSA) surveillance system may be beneficial. It is generally thought that change to the usual practice of follow-up of prostate cancer patients is required.

Understanding factors that inhibit or promote the utilization of telecare in chronic lung disease

OBJECTIVES

To perform a process evaluation of a randomized controlled trial (RCT) of home telecare for the management of acute exacerbations of chronic obstructive pulmonary disease (COPD), using the normalization process model (NPM) as an explanatory framework.

METHODS

Semi-structured interviews were carried out with patients (n = 9) and nurses (n = 11) participating in a RCT. A framework approach to data analysis was used.

RESULTS

The telecare service did not provide an interactional advantage for the nurses providing this service and did not fit with the nurses' views of the most appropriate or preferred use of their skills. The telecare service seemed unlikely to become normalized as part of routine healthcare delivery, because the nursing team lacked confidence that it was a safe way to provide healthcare in this context and it was not perceived as improving efficiency.

DISCUSSION

The NPM effectively mapped onto the study findings and explained those factors that inhibited the routine delivery of COPD services by telecare.

Attitudes to the public release of comparative information on the quality of general practice care: qualitative study

OBJECTIVES

To examine the attitudes of service users, general practitioners, and clinical governance leads based in primary care trusts to the public dissemination of comparative reports on quality of care in general practice, to guide the policy and practice of public disclosure of information in primary care.

DESIGN

Qualitative focus group study using mock quality report cards as prompts for discussion.

SETTING

12 focus groups held in an urban area in north west England and a semirural area in the south of England.

PARTICIPANTS

35 service users, 24 general practitioners, and 18 clinical governance leads.

RESULTS

There was general support for the principle of publishing comparative information, but all three stakeholder groups expressed concerns about the practical implications. Attitudes were strongly influenced by experience of comparative reports from other sectors-for example, school league tables. Service users distrusted what they saw as the political motivation driving the initiative, expressed a desire to "protect" their practices from political and managerial interference, and were uneasy about practices being encouraged to compete against each other. General practitioners focused on the unfairness of drawing comparisons from current data and the risks of "gaming" the results. Clinical governance leads thought that public disclosure would damage their developmental approach to implementing clinical governance. The initial negative response to the quality reports seemed to diminish on reflection.

CONCLUSIONS

Despite support for the principle of greater openness, the planned publication of information about quality of care in general practice is likely to face considerable opposition, not only from professional groups but also from the public. A greater understanding of the practical implications of public reporting is required before the potential benefits can be realised.

Subcellular distribution of aquaporin 5 in salivary glands in primary Sjögren's syndrome

Secretions from salivary and lacrimal glands are reduced in patients with primary Sjögren's syndrome (PSS). Since aquaporin 5 is involved in transport of water and is present in salivary and lacrimal glands, this protein was thought to have a major role in the pathogenesis of PSS. We used indirect immunofluorescence and an immunoperoxidase technique to assess expression and subcellular localisation of aquaporin 5 in patients and controls. Our results suggest that the distribution and density of aquaporin 5 in salivary glands does not differ between patients with PSS and those without. Thus, the role of aquaporin 5 in the pathogenesis of PSS needs to be reassessed and alternative pathogenetic mechanisms investigated.

Neuropeptide Y-immunoreactive neurons in the retina of two Australian lizards

Wholemounts and sectioned retina from adults of two lizard species, Pogona vitticeps and Varanus gouldii, were studied by immunohistochemistry for neuropeptide Y (NPY)-like immunoreactivity. In both species the morphology of two classes of amacrine cells (types A and B) were described. Cell somata were located mostly in the inner nuclear layer (INL) but were occasionally displaced into the ganglion cell layer (GCL). In the Pogona retina, type A cells had large somata and dendritic arbor that branched in sublamina (S) 1 and 2/3 of the inner plexiform layer (IPL). Type B amacrine cells had smaller somata and dendritic arbor branching mostly in S5 of the IPL. In the Varanus retina, the levels of dendritic branching of types A and B amacrine cells in the IPL were similar to those in Pogona although branching in the middle of the IPL occurred at S3. NPY-immunoreactive cells with small somata and narrow to medium sized dendritic fields were predominant. Unclassified cells also displayed NPY-like immunoreactivity; however, their dendritic morphology could not be determined due to the faint and inconsistent staining. In transverse retinal sections three bands of NPY-like immunoreactivity were evident in the IPL of both species, to which the unclassified cells also contributed. In both species type A cells were most numerous. Total NPY-immunoreactive cells were estimated to be 8,600 in Pogona and 32,860 in Varanus. In both species types A and B cells were non-uniformly distributed across the retina. The most apparent non-uniformity in distribution was observed in type A cells in Varanus. Peak cell density was found across the horizontal meridian of the retina from where cell density decreased towards the dorsal and ventral retinal margins. The results of this study provide evidence for the presence of NPY-immunoreactive amacrine cells in the lizard retina of which two types were morphologically characterized. Cross-species comparisons were also made among NPY-immunoreactive amacrine cells, and their possible function/s discussed.

Children's understanding of conflicting emotions: a training study

Notwithstanding a substantial body of evidence indicating that young children have difficulty in understanding conflicting emotions, we predicted that training would likely be effective in promoting an ability to understand. This prediction was made in the light of recent research that has demonstrated young children's competence in understanding conflicting beliefs and desires, a competence that is seen as contingent upon the possession of a representational theory of mind (Perner, 1991). The experiment involved two groups of 6-year-olds, one of which had undergone brief training. Ten weeks following training, both groups watched a video recording of an event that could be seen to give rise to both positive and negative emotions. As predicted, children in the experimental group gave significantly more evidence of understanding conflicting emotions than did those in the control group. Surprisingly, even within the control group, many children understood conflicting emotions. Possible explanations for the precocious performance of children in the control group are discussed, as are caveats relating to the major findings of the study.

Substance P-immunoreactive neurons in the retina of two lizards

The dendritic morphology and retinal distribution of substance P(SP)-immunoreactive neurons was determined in two Australian lizard species Pogona vitticeps and Varanus gouldii, by using immunohistochemistry on retinal wholemounts and sectioned materials. In both species, two classes of SP-immunoreactive neurons were described in the inner nuclear layer (INL) and classified as amacrine cells (types A and B). Type A amacrine cells had large somata and wide-field, bistratified dendrites branching in sublaminas 1 and 5 of the inner plexiform layer (IPL). Their morphology and retinal distribution differed between the two species. Type B amacrine cells in both species had small somata and small-field dendritic branching. A population of SP-immunoreactive neurons with classical ganglion cell morphology were identified in the ganglion cell layer (GCL). Immunostained ganglion cells occurred in larger numbers of Varanus gouldii than in Pogona vitticeps. In both species type B SP cells were the most numerous and were estimated to be about 60,000-70,000. They were distributed non-uniformly with a high density band across the horizontal meridian of the retina, from where the density decreased towards the dorsal and ventral retinal margins. In both species type A amacrine cells occurred in small numbers distributed sparsely in the peripheral retina. The faint immunostaining of SP-immunoreactive neurons in the GCL, did not allow us to reliably determine their numbers and retinal distribution. The functional significance of SP-immunoreactive amacrine and ganglion cells in the lizard retina remains to be determined.

The changing distribution of neurons in the inner nuclear layer from metamorphosis to adult: a morphometric analysis of the anuran retina

The generation and changing distribution of neurons of the inner nuclear layer (INL) in the retina of two anuran species, Bufo marinus and Xenopus laevis, were studied from metamorphosis to adult. Morphometric studies were undertaken at six developmental stages in Bufo and four in Xenopus. The number and thickness of neurons in the INL were established in 29 predetermined retinal locations from serial sections of the eyes cut vertically or horizontally. The total number of neurons in the INL increased from metamorphosis to adult from 826,000 +/- 185 to 18,760,000 +/- 562 (mean +/- SD) in Bufo and from 308,000 +/- 25 to 877,000 +/- 31 in Xenopus. Over the same period the surface area of the INL increased about 50-fold from 2 mm2 to 96 mm2 in Bufo and 5-fold from 2.5 mm2 to 13 mm2 in Xenopus. In Bufo the difference between the highest cell number (central-temporal retina) and the lowest cell number in a sample area (dorsal and ventral peripheral retina) was 2.1:1 at metamorphosis. This ratio increased to 3.4:1 in the adult. Both the cell number and cell density per sample area in the INL was found to be higher along the nasotemporal meridian of the eye overlying the visual streak of the ganglion cell layer (GCL) of the retina. The retinal distribution of neurons in the INL did not change significantly during postmetamorphic growth in Xenopus. At metamorphosis a 1.7:1 difference was found between the highest neuron number (retinal ciliary margin) and lowest neuron number (retinal centre) decreasing to 1.5:1 in the adult. Retinae were labelled with 3H-thymidine in 15 mm Bufos and examined 2, 6, 12 and 18 weeks later. Higher rates of cell addition to the nasal and temporal poles of the INL were found compared with that at the dorsal and ventral poles. The retinal radial growth at the ciliary margin of the dorsal, ventral, nasal and temporal poles between the time of isotope injection and 18 weeks survival was found to be uneven; more radial elongation occurred at the nasal, dorsal and ventral poles and less at the temporal pole. These observations suggest that (a) the neuron distribution of the INL in adult animals approximates that of the GCL and (b) the visual streak-like area of the INL in Bufo develops by a sustained differential cell addition at the temporal and nasal poles of the retina.

Neuropeptide Y- and substance P-like immunoreactive amacrine cells in the retina of the developing Xenopus laevis

The development of neuropeptide Y-like (NPY-LI) and substance P-like (SP-LI) immunoreactive neurons was studied in retinas of Xenopus laevis from young tadpole through to adult animals. In adult retina these neuropeptides are present in wide-field amacrine cells located in the inner nuclear layer and the ganglion cell layer of the retina. Retinal wholemount preparations and sectioned material showed that immunoreactive cells appeared during early larval life and NPY-LI occurred earlier than SP-LI cells. The primary dendritic branching of NPY-LI neurons appeared from early larval life whilst SP-LI was evident in dendrites from mid-larval stages. In postmetamorphic animals the numbers of immunoreactive cells increased in proportion to retinal area growth with a relatively constant cell density of about 35 cells/mm2 for SP-LI and 45 cells/mm2 for NPY-LI. The maturation of dendritic morphology of both NPY- and SP-LI amacrine cells appeared later in larval development than the appearance of immunoreactivity in cell somas. However, the sequence of expression of NPY- or SP-LI and their dendritic maturation was different for the two classes of amacrine cells. It is suggested that the maturation of dendritic fields of amacrine cells is complete just prior to metamorphosis, consistent with the postmetamorphic onset of electrophysiological features of ganglion cells attributed to amacrine cells.

Neuropeptide Y-like immunoreactive amacrine cells in the retina of Bufo marinus

Neuropeptide Y-like immunoreactive (NPY-LI) amacrine cells of the Bufo marinus retina were morphologically characterized, and their retinal distribution was established using immunohistochemistry on retinal wholemount preparations and sectioned material. The somas of NPY-LI amacrine cells were situated in the innermost part of the inner nuclear layer and their dendrites branched primarily in the scleral sublamina of the inner plexiform layer. A subgroup of the NPY-LI cells had dendrites in both the scleral and vitreal sublamina. All immunoreactive cells had large dendritic fields (average 0.5 mm2) that resulted in a high dendritic overlap across the retina. NPY-LI amacrine cells were evenly distributed across the retina, with an average density of 30 cells/mm2, although higher densities were observed at regions adjacent to the ciliary margin. The dendritic field size of the NPY-LI cells, together with the previously characterized substance P-like immunoreactive (SP-LI) amacrine cells, indicates that they belong to the class of wide-field amacrine cells. However, unlike the SP-LI neurons whose dendrites branch in the vitreal sublamina of the inner plexiform layer, the dendrites of the majority of the NPY-LI neurons branch in the scleral sublamina.

Morphological characterization of substance P-like immunoreactive amacrine cells in the anuran retina

Using substance P immunohistochemistry it was possible to demonstrate a class of morphologically homogeneous group of neurons in the inner nuclear layer (INL) of the retina of two anuran species: Xenopus laevis and Bufo marinus. The number of cells with substance P-like immunoreactivity (SP-LI) was about 250 and 800 in juvenile and 600 and 2500 in adult Xenopus and Bufo, respectively, SP-LI cells had a small soma with one primary dendrite having up to four slender branches, located in the vitreal sublamina of the inner plexiform layer (IPL). Mean dendritic field sizes were 0.12 and 0.30 mm2 in juvenile and 0.29 and 0.65 mm2 in adult Xenopus and Bufo, respectively. The density of SP-LI cells was 40/mm2 in juvenile and 24/mm2 in adult Xenopus compared with 20/mm2 in juvenile and 13/mm2 in adult Bufo. Nearest neighbour distance measurements indicated that SP-LI cells were randomly distributed across the entire retina in both species. The location and the morphology of SP-LI cells indicated that they correspond to a subclass of wide-field amacrine cells, similar to types 20 and 21 described by Golgi techniques in the cat.

Neuropeptide Y-like immunoreactivity in neurons of the human retina

The distribution of neuropeptide Y-like immunoreactivity (NPY-LI) was investigated in wholemounts and in transverse sections of the human retina. NPY-LI was localized to the soma and axonal processes of large ganglion cells (GCs) and to the soma and dendritic arborization of amacrine cells (ACs). NPY-LI GCs were unevenly distributed across the retina, the highest density of 875 cells/mm2 was found in the fovea centralis and the lowest density of 15 cells/mm2 in the peripheral retina. The total number of NPY-LI GCs in the retina was estimated to be about 85,000. The soma sizes of NPY-LI GCs increased from 116 microns 2 +/- 23 (s.d.) in the retinal centre to 251 microns 2 +/- 57 in the retinal periphery. The soma size of NPY-LI ACs was in the range of 40 and 50 microns 2. In transverse sections NPY-LI was seen to be localized to the optic fibre layer, to the somata of GCs, to the scleral sublamina of the inner plexiform layer (AC dendrites) and to the innermost part of the inner nuclear layer (somata of ACs). The gradients of soma sizes and retinal distribution of NPY-LI GCs were taken as an indication that they correspond to the class of large to very large GCs, previously identified in the human retina by Golgi impregnation.

The formation of axonal projections of the mesencephalic trigeminal neurones in chick embryos

Horseradish peroxidase-wheat germ agglutinin conjugate (HRP) was injected into masticatory and eye muscles of 6- to 15-day-old chick embryos and posthatched chicks to establish the timetable of axonal outgrowth and distribution of central and peripheral terminations of mesencephalic trigeminal neurones (MTN). HRP-labelled MTN first appeared on the 10th day of incubation and by the 14th day most of MTN became labelled, indicating that axonic outgrowth to peripheral targets occurred between the 10th and 14th days of incubation. Peripheral targets included the pterygoideus lateralis and medialis, protractor quadratus, pseudotemporalis superficialis and profundus, and adductor mandibulae of jaw-closing muscles. HRP-filled central axonic processes of MTN were identified first on the 13th day of incubation and they terminated exclusively in the motor nucleus of the trigeminal nerve. Between the 10th and 13th days of incubation, at the peak of naturally occurring cell death in the MTN pool, a consistently lower percentage of neurones could be labelled with HRP than in older embryos and in posthatched chicks. This finding suggests that many MTN die before establishing contact with peripheral targets.

The development of the neurons of the glossopharyngeal (IX) and vagal (X) sensory ganglia in chick embryos

The timetable of cell generation, neuronal death and neuron numbers in the fused proximal glossopharyngeal (IX) and vagal (X) ganglion and distal IX and X ganglia were studied in normal and nerve growth factor (NGF) treated chick embryos. 3H-thymidine was injected between the 3rd and 7th days of incubation and embryos sacrificed on the 11th day. Neurons in the distal IX and X ganglia were generated between the 2nd and 5th days of incubation, the peak mitotic activity occurring on the 4th and 3rd days, respectively. Neurons of the proximal IX and X ganglion were generated between the 4th and 7th days, with maximum neuron generation on the 5th day of incubation. Counts of neurons in the 3 ganglia between the 5th and 18th days of incubation showed a maximum of 22,000 on the 8th day in the proximal IX and X ganglion and this decreased to 12,000 by the 13th day. In the distal IX ganglion, the neuron number decreased by 44% from 4,500 on the 6th day to 2,500 by the 11th day. A similar decrease of 43% was found in the distal X ganglion, the neuron number falling from 11,500 on the 7th day to 6,500 by the 11th day of incubation. Neuronal cell death in these ganglia extended from the 5th to the 12th day of incubation, maximum cell death occurring at or after the cessation of mitotic activity. NGF administration from the 5th to the 11th day of incubation did not have a measurable effect on the neurons of proximal IX and X and distal IX ganglia, but increased neuronal survival by 30% in the distal X ganglion.(ABSTRACT TRUNCATED AT 250 WORDS)

Post-metamorphic retinal growth in Xenopus

The postmetamorphic growth of the retina in Xenopus was studied using 3H-thymidine ( 3HT ) autoradiography and quantitative morphometric assays. 3HT was administered to tadpoles at stages 58, 62 and 66 and the animals sacrificed between 3 weeks and 12 months after metamorphosis. Reconstructions were made from serial sections and the position of labelled cell groups in the retina were established. On the reconstructed retina, regions formed up to stage 58, between stages 58 and 66 and after metamorphosis were measured. The area of the dorsal, ventral, temporal and nasal retinal halves was also determined from stage 58 through to adult. The entire retinal area increased 10-fold from stage 58 to 12 months after metamorphosis, the fastest growing region being the retinal periphery due to continuous cell addition at the ciliary margin. Concommitant with the retinal area growth, the number of ganglion cells increased from 20,000 to 85,000 over the time of investigation. Asymmetric cell addition to the ciliary margin from stage 58 onwards resulted in a predominantly crescentic retinal growth along the nasoventral ciliary margin. Consequently, the optic nerve head became displaced away from the geometric centre of the eye into the dorso-temporal retinal quadrant. These results suggest that besides a sustained cell production exclusively at the ciliary margin, a passive area expansion contributes to the overall retinal growth from the metamorphic climax to adulthood. It is also apparent that the steady increase of the number of retinal ganglion cells and optic fibers necessitates a continuous remodelling of the retinotectal connections throughout the lifespan of the animal.

Aberrant retinotectal projection induced by larval unilateral enucleation in Xenopus

The left eye was removed at late larval stages in Xenopus and the optic fibre projections of the remaining right eye assessed from 2 weeks to 13 months past metamorphosis. [3H]Proline autoradiography and electrophysiological recording of the visual field projection showed an aberrant optic fibre projection from the peripheral ventral retina to the right ipsilateral tectum. It is suggested that optic fibres, arising from the retina formed after the time of the operation, reach the ipsilateral tectum by following the axon debris of the removed eye.

Peripheral and central terminations of axons of the mesencephalic trigeminal neurons in Xenopus

Following injection into masticatory and extraocular muscles, the peripheral and central distributions of the axonic processes of mesencephalic trigeminal neurons (MTC) were studied with the aid of retrograde and anterograde transport of horseradish peroxidase. Peripheral projections included the superior rectus, inferior rectus, superior oblique and the temporalis muscles. Central axonic processes of MTC terminated in the oculomotor--trochlear nuclear complex and in the motor nucleus of the trigeminal nerve.

Temporo-nasal asymmetry in the accretion of retinal ganglion cells in late larval and postmetamorphic Xenopus

The spatial pattern of cell production and retinal growth were studied in Xenopus between stage 60 and two months after metamorphosis using 3H-proline and 3H-thymidine autoradiography. The position and the number of the ganglion cells labelled with 3H-thymidine were determined. The area of the unlabelled retina due to growth since 3H-proline administration at stage 60 was measured. Both retinal area measurements and counts of labelled ganglion cells showed 30-40% higher values in the temporal than in the nasal retinal half. The greater cell production and area accretion were even more pronounced between the temporal and the nasal retinal quadrants. The results on the temporoventral crescentic retinal growth rule out the possibility that from midlarval stages onwards the retinal and the tectal growth patterns are matched.

Segregation of optic fibre projections into eye-specific bands in dually innervated tecta in Xenopus

The restoration of the retinotectal projections following metamorphic bilateral optic nerve sections was studied in Xenopus 20 weeks after operation, using [3H]proline autoradiography and electrophysiological mapping. Optic fibre projections from each eye to both tecta segregated into eye-specific termination bands with some overlap at the borders. The bands were arranged rostrocaudally in the tecta such that each eye had an alternating representation. Despite the segregation of the optic fibres, each eye had a complete visual (retinal) projection with the normal nasotemporal and dorsoventral polarities of the visual field maintained. The results suggest competition for preferred terminal sites between the two sets of optic fibres in dually innervated tecta.