265 research outputs found
Evaluating non-randomised intervention studies
No full textBackground
In the absence of randomised controlled trials (RCTs), healthcare practitioners and policy-makers rely on non-randomised studies to provide evidence of the effectiveness of healthcare interventions. However, there is controversy over the validity of non-randomised evidence, related to the existence and magnitude of selection bias.
Objectives
To consider methods and related evidence for evaluating bias in non-randomised intervention studies.
Methods
1. Three reviews were conducted to consider:
empirical evidence of bias associated with non-randomised studies
the content of quality assessment tools for non-randomised studies
the use of quality assessment in systematic reviews of non-randomised studies.
These reviews were conducted systematically, identifying relevant literature through comprehensive searches across electronic databases, handsearches and contact with experts.
2. New empirical investigations were conducted generating non-randomised studies from two large, multicentre RCTs by selectively resampling trial participants according to allocated treatment, centre and period. These were used to examine:
systematic bias introduced by the use of historical and non-randomised concurrent controls
whether results of non-randomised studies are more variable than results of RCTs
the ability of case-mix adjustment methods to correct for selection bias introduced by non-random allocation.
The resampling design overcame particular problems of meta-confounding and variability of direction and magnitude of bias that hinder the interpretation of previous reviews.
Results
Empirical comparisons of randomised and non-randomised evidence
Eight studies compared results of randomised and non-randomised studies across multiple interventions using meta-epidemiological techniques. The studies reached conflicting conclusions, explicable by differences in:
whether data were sourced from primary studies or systematic reviews
consideration of meta-confounding
inclusion of studies of varying quality
criterion for classifying discrepancies in results.
The only deducible conclusions were (a) results of randomised and non-randomised studies sometimes, but not always, differ and (b) both similarities and differences may often be explicable by other confounding factors.
Quality assessment tools for evaluating non-randomised studies
We identified 194 tools that could be or had been used to assess non-randomised studies. Around half were scales and half checklists, most were published within systematic reviews and most were poorly developed with scant attention paid to principles of scale development.
Sixty tools covered at least five of six pre-specified internal validity domains (creation of groups, blinding, soundness of information, follow-up, analysis of comparability, analysis of outcome), although the degree of coverage varied. Fourteen tools covered three of four core items of particular importance for non-randomised studies (How allocation occurred? Was the study designed to generate comparable groups? Were prognostic factors identified? Was case-mix adjustment used?). Six tools were thought suitable for use in systematic reviews.
Use of quality assessment in systematic reviews of non-randomised studies
Of 511 systematic reviews that included non-randomised studies, only 169 (33%) assessed study quality. Many used quality assessment tools designed for RCTs or developed by the authors themselves, and did not include key quality criteria relevant to non-randomised studies. Sixty-nine reviews investigated the impact of quality on study results in a quantitative manner.
Empirical estimates of bias associated with non-random allocation
The bias introduced by non-random allocation was noted to have two components. First, the bias could lead to consistent over- or underestimations of treatment effects. This occurred for historical controls, the direction of bias depending on time trends in the case-mix of participants recruited to the study. Second, the bias increased variation in results for both historical and concurrent controls, owing to haphazard differences in case-mix between groups. The biases were large enough to lead studies falsely to conclude significant findings of benefit or harm.
Empirical evaluation of case-mix adjustment methods
Four strategies for case-mix adjustment were evaluated: none adequately adjusted for bias in historically and concurrently controlled studies. Logistic regression on average increased bias. Propensity score methods performed better, but were not satisfactory in most situations. Detailed investigation revealed that adequate adjustment can only be achieved in the unrealistic situation when selection depends on a single factor. Omission of important confounding factors can explain underadjustment. Correlated misclassifications and measurement error in confounding variables may explain the observed increase in bias with logistic regression, as may differences between conditional and unconditional odds ratio estimates of treatment effects.
Conclusions
Results of non-randomised studies sometimes, but not always, differ from results of randomised studies of the same intervention. Non-randomised studies may still give seriously misleading results when treated and control groups appear similar in key prognostic factors. Standard methods of case-mix adjustment do not guarantee removal of bias. Residual confounding may be high even when good prognostic data are available, and in some situations adjusted results may appear more biased than unadjusted results.
Although many quality assessment tools exist and have been used for appraising non-randomised studies, most omit key quality domains. Six tools were considered potentially suitable for use in systematic reviews, but each requires revision to cover all relevant quality domains.
Healthcare policies based upon non-randomised studies or systematic reviews of non-randomised studies may need re-evaluation if the uncertainty in the true evidence base was not fully appreciated when policies were made.
The inability of case-mix adjustment methods to compensate for selection bias and our inability to identify non-randomised studies which are free of selection bias indicate that non-randomised studies should only be undertaken when RCTs are infeasible or unethical
Development and pilot evaluation of a complex intervention to improve experienced continuity of care in patients with cancer
No full textHigh experienced continuity of care in patients with cancer is associated with lower needs for care, better quality of life and better psychological outcomes. We developed and evaluated an intervention to improve experienced continuity. The intervention, consisted of (1) a 17-item patient-completed continuity assessment; (2) feedback to clinical nurse specialists and action to address the needs identified. Multidisciplinary team meetings and oncology outpatient clinics were observed, and patients and staff were interviewed. After qualitative work and reliability testing, the intervention was evaluated in a feasibility trial. Sixty-one patients provided data for analysis. No statistically significant differences were found in patients' experienced continuity between the trial arms, but important trends were seen in measures of needs for care in favour of those receiving the intervention. Feeding back findings from the continuity assessment to clinicians reduced patients' needs for care. Our results indicate that an intervention to target patients' experiences of continuity can reduce their subsequent needs for care. However, overcoming barriers to organisational change and addressing some patients' hesitation to report their continuity difficulties must be considered when implementing such an intervention. A phase III trial targeting patients with inadequate experienced continuity of care is recommended
Extended scope of nursing practice: a multicentre randomised controlled trial of appropriately trained nurses and pre-registration house officers in pre-operative assessment in elective general surgery
No full textAim/ Principal Research Question:1) To determine whether pre-operative assessment carried out by an appropriately trained nurse (ATN) is equivalent in quality to that carried out by a pre-registration house officer (PRHO).2) To assess whether pre-assessments carried out by ATNs and PRHOs are equivalent in terms of cost.3) To determine whether assessments carried out by ATNs are acceptable to patients.4) To investigate the quality of communication between senior medical staff and ATNs.Factors of Interest:The extended role of appropriately trained nurses and pre-registration house officers in pre-operative assessment in elective general surgery.Methods:The study design was principally a prospective randomised equivalence trial but was accompanied by additional qualitative assessment of patient and staff perceptions, and an economic evaluation.The intervention consisted of a pre-operative assessment carried out by either an ATN or a PRHO. Of the patients who completed the study with a full evaluation, 926 patients were randomised to the PRHO arm of the trial and 948 to the ATN arm. Three ATNs took part in the study, one from each centre, together with a total of 87 PRHOs.Immediately following the initial assessment of a patient by a PRHO or an ATN, one of a number of clinical research fellows, all specialist registrars in anaesthetics, repeated the assessment and recorded it on a study form, together with a list of investigations required. The clinical research fellow then evaluated the competency of the initial assessor by comparing the quality of their assessment with their own. Any deficiencies in ordering of investigations and referral to other specialities were met in order to maximise patient care.Sample groups:All patients attending at one site for assessment prior to general anaesthetic for elective general, vascular, urological or breast surgery were potentially included in the study. Of 1907 patients who were randomised, 1874 completed the study with a full evaluation.The study was carried out at four NHS hospitals, three of which were teaching hospitals, in three NHS Trusts in Southampton, Sheffield and Doncaster.Outcome measures:Three areas of ATN and PRHO performance were judged separately, history taking, examination and ordering of tests, and each was graded into one of four categories, the most important of which was under-assessment, which would possibly have affected peri-operative management. In the case of ordering of tests, it was possible to have both over- and under-assessed a patient on different tests.Findings:The pre-operative assessments carried out by the ATNs were essentially equivalent to those performed by the PRHOs in terms of under-assessment that might possibly have affected peri-operative management, although there was variation between the ATNs in terms of the quality of history taking. This may be related to the low number of patients seen at one study site.PRHOs ordered significantly more unnecessary tests than the ATNs. The substitution of ATNs for PRHOs was calculated to be cost neutral.The results of the qualitative assessment showed that the use of ATNs for pre-operative assessment was acceptable to patients; however, there was no evidence that communication between senior medical staff and those carrying out pre-operative assessments was improved by their introduction.Conclusions:This study demonstrated no reason to inhibit the development of fully nurse-led pre-operative assessment, provided that the nurses are appropriately trained and maintain sufficient workload to retain skills.Implications for Further Research:Further research is needed in the following areas:1) the extent and type of training needed for nurses undertaking the pre-operative assessment role2) the use, costs and benefits of routine pre-operative testing.<br/
Achieving teamwork: a grounded theory investigation in selected stroke units in the north of England
No full textThe development of collaborative interdisciplinary working is a key element of contemporary health policy. Future healthcare workers will need to work. individually, collaboratively and in teams if they are to meet the complex and changing needs of the patients they serve. The literature related to health professional team working identifies many barriers and sources of potential
conflict, but there is also evidence that effective interdisciplinary teamwork can be achieved and is
associated with improved health outcomes. The specialised and co-ordinated multidisciplinary team care provided in stroke units was considered to contribute directly to the improved patient outcomes seen in these units. However, the ways in which stroke unit team members co-ordinate their work was not clearly understood.
This study utilised a grounded theory approach to develop an explanation of the ways in which health professionals in two stroke rehabilitation units in the North of England achieved teamwork. Data were generated through over 200 hours of participant observation and thirty four semistructured interviews with a range of team members.
The findings of the study identified a basic social process which was common to team working in both stroke units; this process was termed 'opportunistic dialogue'. This represented an interactional process through which the division of labour in respect of specific rehabilitation
activities was worked out and agreed by team members on a day-to-day basis. Co-location of most team members in both units led to repeated engagement in sharing and validating patient information and in exploring different perspectives. Opportunistic dialoguing contributed to mutual
learning in the stroke unit teams and explained the shift in thinking and team culture which occurred as team members moved from concern with discrete disciplinary actions to dialogue and negotiations focused on collaboration to meet the needs of stroke patients.
Negotiations played a major role in opportunistic dialogue and coming to agreement on the teams' rehabilitation work. The study findings emphasised the interrelatedness and interdependence of these concepts as core interactional processes contributing to the achievement of teamwork in
stroke units. The study confirmed the utility of the negotiated order perspective in understanding and explaining workplace interactions, but identified that whilst negotiations were a key feature of opportunistic dialogue, other processes also contributed to achieving and maintaining teamwork. Focussing on dialogue demonstrated that patterned talk-in-interaction processes maximised the
contribution of opportunistic dialogue to coordinating the skills and knowledge of the different disciplines participating in stroke rehabilitation. The achievement of teamwork in these units occurred through access to and participation in opportunistic dialogue
First steps: study protocol for a randomized controlled trial of the effectiveness of the Group Family Nurse Partnership (gFNP) program compared to routine care in improving outcomes for high-risk mothers and their children and preventing abuse.
No full textBACKGROUND: Evidence from the USA suggests that the home-based Family Nurse Partnership program (FNP), extending from early pregnancy until infants are 24 months, can reduce the risk of child abuse and neglect throughout childhood. FNP is now widely available in the UK. A new variant, Group Family Nurse Partnership (gFNP) offers similar content but in a group context and for a shorter time, until infants are 12 months old. Each group comprises 8 to 12 women with similar expected delivery dates and their partners. Its implementation has been established but there is no evidence of its effectiveness. METHODS/DESIGN: The study comprises a multi-site randomized controlled trial designed to identify the benefits of gFNP compared to standard care. Participants (not eligible for FNP) must be either aged < 20 years at their last menstrual period (LMP) with one or more previous live births, or aged 20 to 24 at LMP with low educational qualifications and no previous live births. 'Low educational qualifications' is defined as not having both Maths and English Language GCSE at grade C or higher or, if they have both, no more than four in total at grade C or higher. Exclusions are: under 20 years and previously received home-based FNP and, in either age group, severe psychotic mental illness or not able to communicate in English. Consenting women are randomly allocated (minimized by site and maternal age group) when between 10 and 16 weeks pregnant to either to the 44 session gFNP program or to standard care after the collection of baseline information. Researchers are blind to group assignment.The primary outcomes at 12 months are child abuse potential based on the revised Adult-Adolescent Parenting Inventory and parent/infant interaction coded using the CARE Index based on a video-taped interaction. Secondary outcomes are maternal depression, parenting stress, health related quality of life, social support, and use of services. DISCUSSION: This is the first study of the effectiveness of gFNP in the UK. Results should inform decision-making about its delivery alongside universal services, potentially enabling a wider range of families to benefit from the FNP curriculum and approach to supporting parenting. TRIAL REGISTRATION: ISRCTN78814904
74 Trial-CARE: Centralized Support Services for Investigator-Initiated Multi-Site Clinical Trials
No full textOBJECTIVES/GOALS: To describe the impact of Trial-CARE (Coordination, Acceleration, and Recruitment Enhancement), a centralized service core at Washington University (WU), aimed at enhancing the capability of investigator-initiated multi-site clinical trials at WU and partner CTSA institutions. METHODS/STUDY POPULATION: Through review of our marketing materials and service tracking system we defined the following Trial-CARE offerings: Infrastructure: Trial-CARE is a centralized service core at WU. Whereby, a team member is sourced to an investigator-initiated multi-site clinical trial (II-MCT) to ensure the achievement of study milestones across any phase of the clinical trial life cycle. Team: Our team consists of research professionals with expertise in II-MCT project management, data management, and administrative/regulatory management. Services: * One free 60-minute case consultation * Tiers of Service * Academic Research Organization (ARO) support * Clinical Coordinating Center * Data Coordinating Center * II-MCT project management support * Time-limited targeted support RESULTS/ANTICIPATED RESULTS: Trial-CARE has completed 94 consultations in support of WU and partner CTSA institutions enabling the streamlining of study start-up; guidance for study recruitment, implementation, and operations; and offering resources to foster career development. Consultations can be completed at any phase in the clinical trial lifecycle, with Trial-CARE completing: * 12% in the idea phase * 45% in the grant development and submission stage * 28% after funding has been awarded Top reasons researchers connect with Trial-CARE about II-MCTs: * regulatory guidance (40%) * general information about Trial-CARE Services and II-MCTs (35%) * protocol development (21%) * data management (20%) * study budgeting (20%) DISCUSSION/SIGNIFICANCE: In response to a WU wide survey, Trial-CARE plans to generate informational webinars and is creating a clinical trial tracking dashboard, to pro-actively offer support services to researchers prior to grant funding. The goal is also to increase the percentage of consultations completed in the idea phase and the grant development and submission stage
Recruitment to randomised trials : Strategies for Trial Enrolment and Participation Study. The STEPS study
No full textObjectives: To identify factors associated with good and poor recruitment to multicentre trials.
Data sources: Part A: database of trials started in or after 1994 and were due to end before 2003 held by the Medical Research Council and Health Technology Assessment Programmes. Part B: interviews with people playing a wide range of roles within four trials that their funders identified as ‘exemplars’. Part C: a large multicentre trial (the CRASH trial) of treatment for head injury.
Review methods: The study used a number of different perspectives (‘multiple lenses’), and three components. Part A: an epidemiological review of a cohort of trials. Part B: case studies of trials that appeared to have particularly interesting lessons for recruitment. Part C: a single, in-depth case study to examine the feasibility of applying a businessorientated analytical framework as a reference model in future trials.
Results: In the 114 trials found in Part A, less than one-third recruited their original target within the time originally specified, and around one-third had extensions. Factors observed more often in trials that recruited successfully were: having a dedicated trial manager, being a cancer or drug trial, and having interventions only available inside the trial. The most commonly reported strategies to improve recruitment were newsletters and mailshots, but it was not possible to assess whether they were causally linked to changes in recruitment. The analyses in Part B suggested that successful trials were those addressing clinically important questions at a timely point. The investigators were held in high esteem by the interviewees, and the trials were firmly grounded in existing clinical practices, so that the trial processes were not alien to clinical collaborators, and the results could be easily applicable to future practice. The interviewees considered that the needs of patients were well served by participation in the trials. Clinical collaborators particularly appreciated clear delineation of roles, which released them from much of the workload associated with trial participation. There was a strong feeling from interviewees that they were proud to be part of a successful team. This pride fed into further success. Good groundwork and excellent communications across many levels of complex trial structures were considered to be extremely important, including training components for learning about trial interventions and processes, and team building. All four trials had faced recruitment problems, and extra insights into the working of trials were afforded by strategies invoked to address them. The process of the case study in Part C was able to draw attention to a body of research and practice in a different discipline (academic business studies). It generated a reference model derived from a combination of business theory and work within CRASH. This enabled identification of weaker managerial components within CRASH, and initiatives to strengthen them. Although it is not clear, even within CRASH, whether the initiatives that follow from developing and applying the model will be effective in increasing recruitment or other aspects of the success of the trial, the reference model could provide a template, with potential for those managing other trials to use or adapt it, especially at foundation stages. The model derived from this project could also be used as a diagnostic tool if trials have difficulties and hence as a basis for deciding what type of remedial action to take. It may also be useful for auditing the progress of trials, such as during external review.
Conclusions: While not producing sufficiently definitive results to make strong recommendations, the work here suggests that future trials should consider the different needs at different phases in the life of trials, and place greater emphasis on ‘conduct’ (the process of actually doing trials). This implies learning lessons from successful trialists and trial managers, with better training for issues relating to trial conduct. The complexity of large trials means that unanticipated difficulties are highly likely at some time in every trial. Part B suggested that successful trials were those flexible and robust enough to adapt to unexpected issues. Arguably, the trialists should also expect agility from funders within a proactive approach to monitoring ongoing trials. Further research into different recruitment patterns (including ‘failures’) may help to clarify whether the patterns seen in the ‘exemplar’ trials differ or are similar. The reference model from Part C needs to be further considered in other similar and different trials to assess its robustness. These and other strategies aimed at increasing recruitment and making trials more successful need to be formally evaluated for their effectiveness in a range of trials.Not peer reviewedPublisher PD
Do UK based weight management programmes cause weight loss maintenance in adults? A systematic review
No full textThe aim of this dissertation was to examine whether UK based weight management programmes promote weight loss maintenance (follow up of 12 months to assess effectiveness of intervention in weight loss) in adults through the process of a systematic review. The World Health Organisation (WHO) has described obesity as a "global epidemic". Weight management comprises two phases; weight loss and weight loss maintenance. The latter phase is the true goal for obesity and the most difficult element of weight management to achieve. However much less is know about this as compared with the weight loss phase. There is little purpose in committing time and money to reducing obesity if the weight is regained. This is counter-productive and weight loss maintenance is essential to combat the obesity epidemic. Searches were made for relevant information from a variety of scientific online databases and journals,. Seven articles met the inclusion criteria and were analysed in the review. All studies incorporated a multi-component (diet, exercise, behaviur modification) intervention approach. All control and internvetion groups reported weight loss at 12 months when compared with baseline. All groups recieved an intervention. One study reported a significant difference (P<0.05) between groups. Four studies reported on at least one component (diet, physical activity, behaviour modification) however there was not enough information to conclude whether they complied with national guidelines (NICE CG43 and SIGN 115). High attrition rates and loss to follow up are problematic for each study except one. Analysis on an intention to treat basis was common however this is problematic and there are alternative methods which may be more suitable for dealing with missing data
Identifying the key elements of effective leadership in interdisciplinary health and social care teams: Their impact on services, staff and patient outcomes
No full textAims
This study aimed to identify the key elements of effective leadership in interdisciplinary health and social care teams providing community rehabilitation and intermediate care in England, and investigate their impact on services, staff, team dynamics and patient outcomes.
Methods
This mixed methods health services research investigated workforce issues through the use of a range of methods including a literature review, qualitative study and a cross sectional quantitative study. Fifteen staff interviews were conducted during the qualitative study. Data was recorded, transcribed and analysed thematically using a template approach. The cross-sectional study generated data from 10 teams, including 210 staff and 2210 patients.
Results
The results of the qualitative study show that because of the interdisciplinary nature of the workforce in community rehabilitation and intermediate care services and the unique context in which they operate, interdisciplinary team leadership (IdTL) does require a distinctive form of leadership. However, IdTL does demonstrate many of the same elements as generic theories of team leadership.
The quantitative study found that there were significant associations between: Service structure and working practices and IdTL; IdTL and staff and team behavioural dynamics; staff behavioural dynamics and team behavioural dynamics.
No direct relationship was found between IdTL and patient outcomes. Weak statistical relationships were found between staff and team behavioural dynamics, and patient outcomes
Conclusions
The research shows that effective IdTL can significantly improve staff and team behavioural dynamics. There is some indicative evidence of the effect of staff and team behavioural dynamics on patient outcomes. These results were achieved with a sample of only 10 teams, which provides encouragement that leadership in IdTL is worthy of further investigation
Making co-enrolment feasible for randomised controlled trials in paediatric intensive care.
No full textEnrolling children into several trials could increase recruitment and lead to quicker delivery of optimal care in paediatric intensive care units (PICU). We evaluated decisions taken by clinicians and parents in PICU on co-enrolment for two large pragmatic trials: the CATCH trial (CATheters in CHildren) comparing impregnated with standard central venous catheters (CVCs) for reducing bloodstream infection in PICU and the CHIP trial comparing tight versus standard control of hyperglycaemia
- …
