Browsing by Author "McDonald, Alison Mary"

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Clinical and cost-effectiveness of internal limiting membrane peeling for patients with idiopathic full thickness macular hole. Protocol for a Randomised Controlled Trial : FILMS (Full-thickness macular hole and Internal Limiting Membrane peeling Study)
(BMC, 2008-11-03) Lois, Noemi; Burr, Jennifer Margaret; Norrie, John David; Vale, Luke David; Cook, Jonathan Alistair; McDonald, Alison Mary; FILMS Group; University of Aberdeen, School of Medicine & Dentistry, Division of Applied Health Sciences
Background: A full-thickness macular hole (FTMH) is a common retinal condition associated with impaired vision. Randomised controlled trials (RCTs) have demonstrated that surgery, by means of pars plana vitrectomy and post-operative intraocular tamponade with gas, is effective for stage 2, 3 and 4 FTMH. Internal limiting membrane (ILM) peeling has been introduced as an additional surgical manoeuvre to increase the success of the surgery; i.e. increase rates of hole closure and visual improvement. However, little robust evidence exists supporting the superiority of ILM peeling compared with no-peeling techniques. The purpose of FILMS (Fullthickness macular hole and Internal Limiting Membrane peeling Study) is to determine whether ILM peeling improves the visual function, the anatomical closure of FTMH, and the quality of life of patients affected by this disorder, and the cost-effectiveness of the surgery. Methods/Design: Patients with stage 2–3 idiopathic FTMH of less or equal than 18 months duration (based on symptoms reported by the participant) and with a visual acuity ≤ 20/40 in the study eye will be enrolled in this FILMS from eight sites across the UK and Ireland. Participants will be randomised to receive combined cataract surgery (phacoemulsification and intraocular lens implantation) and pars plana vitrectomy with postoperative intraocular tamponade with gas, with or without ILM peeling. The primary outcome is distance visual acuity at 6 months. Secondary outcomes include distance visual acuity at 3 and 24 months, near visual acuity at 3, 6, and 24 months, contrast sensitivity at 6 months, reading speed at 6 months, anatomical closure of the macular hole at each time point (1, 3, 6, and 24 months), health related quality of life (HRQOL) at six months, costs to the health service and the participant, incremental costs per quality adjusted life year (QALY) and adverse events. Discussion: FILMS will provide high quality evidence on the role of ILM peeling in FTMH surgery. Trial registration: This trial is registered with Current Controlled Trials ISRCTN number 33175422 and Clinical Trials.gov identifier NCT00286507.
Effectiveness and cost-effectiveness of arthroscopic lavage in the treatment of osteoarthritis of the knee: a mixed methods study of the feasibility of conducting a surgical placebo-controlled trial (the KORAL study)
(2010-01-01) Campbell, Marion Kay; Skea, Zoe Christina; Sutherland, Alasdair George; Cuthbertson, Brian; Entwistle, Vikki Ann; McDonald, Alison Mary; Norrie, John David Taylor; Carlson, R V; Bridgman, S; KORAL study group; University of Aberdeen.Other Applied Health Sciences; University of Aberdeen.Institute of Applied Health Sciences; University of Aberdeen.Applied Medicine; University of Aberdeen.Aberdeen Centre for Evaluation
Financial considerations in the conduct of multi-centre randomised controlled trials: evidence from a qualitative study.
(Trials, 2006-12-21) Snowdon, Claire; Elbourne, Diana R.; Garcia, Jo; Campbell, Marion Kay; Entwistle, Vikki; Francis, David; Grant, Adrian Maxwell; Knight, Rosemary C.; McDonald, Alison Mary; Roberts, Ian; University of Aberdeen, School of Medicine & Dentistry, Division of Applied Health Sciences
Marketing and clinical trials : a case study
(BioMed Central, 2007-11-20) Francis, David; Roberts, Ian; Elbourne, Diana R.; Shakur, Haleema; Knight, Rosemary C.; Garcia, Jo; Snowdon, Claire; Entwistle, Vikki; McDonald, Alison Mary; Grant, Adrian Maxwell; Campbell, Marion Kay; University of Aberdeen, School of Medicine & Dentistry, Division of Applied Health Sciences
Background: Publicly funded clinical trials require a substantial commitment of time and money. To ensure that sufficient numbers of patients are recruited it is essential that they address important questions in a rigorous manner and are managed well, adopting effective marketing strategies. Methods: Using methods of analysis drawn from management studies, this paper presents a structured assessment framework or reference model, derived from a case analysis of the MRC's CRASH trial, of 12 factors that may affect the success of the marketing and sales activities associated with clinical trials. Results: The case study demonstrates that trials need various categories of people to buy in – hence, to be successful, trialists must embrace marketing strategies to some extent. Conclusion: The performance of future clinical trials could be enhanced if trialists routinely considered these factors.
Recruitment to randomised trials : Strategies for Trial Enrolment and Participation Study. The STEPS study
(Gray Publishing, 2007-11) Campbell, Marion Kay; Snowdon, Claire; Francis, David; Elbourne, Diana R.; McDonald, Alison Mary; Knight, Rosemary C.; Entwistle, Vikki; Garcia, Jo; Roberts, Ian; Grant, Adrian Maxwell; STEPS Group; University of Aberdeen, School of Medicine & Dentistry, Division of Applied Health Sciences
Objectives: 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.
Single imputation methods were inadequate for missing not at random (MNAR) quality of life data
(BMC, 2008-08-04) Fielding, Shona; Fayers, Peter; McDonald, Alison Mary; McPherson, Gladys Campbell; Campbell, Marion Kay; RECORD Study Group; University of Aberdeen, School of Medicine & Dentistry, Division of Applied Health Sciences
Objective: QoL data were routinely collected in a randomised controlled trial (RCT), which employed a reminder system, retrieving about 50% of data originally missing. The objective was to use this unique feature to evaluate possible missingness mechanisms and to assess the accuracy of simple imputation methods. Methods: Those patients responding after reminder were regarded as providing missing responses. A hypothesis test and a logistic regression approach were used to evaluate the missingness mechanism. Simple imputation procedures were carried out on these missing scores and the results compared to the actual observed scores. Results: The hypothesis test and logistic regression approaches suggested the reminder data were missing not at random (MNAR). Reminder-response data showed that simple imputation procedures utilising information collected close to the point of imputation (last value carried forward, next value carried backward and last-and-next), were the best methods in this setting. However, although these methods were the best of the simple imputation procedures considered, they were not sufficiently accurate to be confident of obtaining unbiased results under imputation. Conclusion: The use of the reminder data enabled the conclusion of possible MNAR data. Evaluating this mechanism was important in determining if imputation was useful. Simple imputation was shown to be inadequate if MNAR are likely and alternative strategies should be considered.
Treatment of Advanced Glaucoma Study : a multicentre randomised controlled trial comparing primary medical treatment with primary trabeculectomy for people with newly diagnosed advanced glaucoma—study protocol
(2018-07) King, Anthony J.; Fernie, Gordon; Azuara-Blanco, Augusto; Burr, Jennifer M.; Garway-Heath, Ted; Sparrow, John M.; Vale, Luke; Hudson, Jemma; MacLennan, Graeme; McDonald, Alison Mary; Barton, Keith; Norrie, John; University of Aberdeen.Aberdeen Centre for Evaluation; University of Aberdeen.Medicine, Medical Sciences & Nutrition; University of Aberdeen.Institute of Applied Health Sciences; University of Aberdeen.Other Applied Health Sciences
What influences recruitment to randomised controlled trials? A review of trials funded by two UK funding agencies.
(Trials, 2006-04-07) McDonald, Alison Mary; Knight, Rosemary C.; Campbell, Marion Kay; Entwistle, Vikki; Grant, Adrian Maxwell; Cook, Jonathan Alistair; Elbourne, Diana R.; Francis, David; Garcia, Jo; Roberts, Ian; Snowdon, Claire; University of Aberdeen, School of Medicine & Dentistry, Division of Applied Health Sciences