Data Sharing in Clinical Trials – Practical guidance on anonymizing trial datasets

There is an increasing demand by non-commercial funders that trialists should provide access to trial data once the primary analysis is completed. This has to take into account concerns about identifying individual trial participants, and the legal and regulatory requirements. Using the good practice guidelines on data sharing laid out by the work funded by the MRC Network of Hubs for Trials Methodology Research, we have devised a processes and mechanisms for user access control, anonymisation and sharing of clinical trial data. As part of this, we have anonymised a dataset from the TOPPIC trial. Using this example, we will present practical guidance on how to anonymise a dataset, and describe rules that could be used on other trial datasets. We will describe how these might differ if the trial was to be made freely available to all, or if the data could only be accessed with specific permission and data usage agreements in place

Divergent confidence intervals among pre-specified analyses in the HiSTORIC stepped wedge trial:an exploratory post-hoc investigation

BACKGROUND: The high-sensitivity cardiac troponin on presentation to rule out myocardial infarction (HiSTORIC) study was a stepped-wedge cluster randomised trial with long before-and-after periods, involving seven hospitals across Scotland. Results were divergent for the binary safety endpoint (type 1 or type 4b myocardial infarction or cardiac death) across certain pre-specified analyses, which warranted further investigation. In particular, the calendar-matched analysis produced an odds ratio in the opposite direction to the primary logistic mixed-effects model analysis. METHODS: Several post-hoc statistical models were fitted to each of the co-primary outcomes of length of hospital stay and safety events, which included adjusting for exposure time, incorporating splines, and fitting a random time effect. We improved control of patient characteristics over time by adjusting for multiple additional covariates using different methods: direct inclusion, regression adjustment for propensity score, and weighting. A data augmentation approach was also conducted aiming to reduce the effect of sparse data bias. Finally, the raw data was examined. RESULTS: The new statistical models confirmed the results of the pre-specified trial analysis. In particular, the observed divergence between the calendar-matched and other analyses remained, even after performing the covariate adjustment methods, and after using data augmentation. Divergence was particularly acute for the safety endpoint, which had an event rate of 0.36% overall. Examining the raw data was particularly helpful to assess the sensitivity of the results to small changes in event rates and identify patterns in the data. CONCLUSIONS: Our experience reveals the importance of conducting multiple pre-specified sensitivity analyses and examining the raw data, particularly for stepped wedge trials with low event rates or with a small number of sites. Before-and-after analytical approaches that adjust for differences in patient populations but avoid direct modelling of the time trend should be considered in future stepped wedge trials with similar designs

Data sharing in clinical trials - practical guidance on anonymising trial datasets

Asthma UK Centre for Applied Research (AUKCAR

A restrictive versus liberal transfusion strategy to prevent myocardial injury in patients undergoing surgery for fractured neck of femur:a feasibility randomised controlled trial (RESULT-NOF)

BackgroundThe optimum transfusion strategy in patients with fractured neck of femur is uncertain, particularly if there is coexisting cardiovascular disease. MethodsWe conducted a prospective, single-centre, randomised feasibility trial of two transfusion strategies. We randomly assigned patients undergoing surgery for fractured neck of femur to a restrictive (haemoglobin, 70–90 g L −1) or liberal (haemoglobin, 90–110 g L −1) transfusion strategy throughout their hospitalisation. Feasibility outcomes included: enrolment rate, protocol compliance, difference in haemoglobin, and blood exposure. The primary clinical outcome was myocardial injury using troponin estimations. Secondary outcomes included major adverse cardiac events, postoperative complications, duration of hospitalisation, mortality, and quality of life. ResultsWe enrolled 200 (22%) of 907 eligible patients, and 62 (31%) showed decreased haemoglobin (to 90 g L −1 or less) and were thus exposed to the intervention. The overall protocol compliance was 81% in the liberal group and 64% in the restrictive group. Haemoglobin concentrations were similar preoperatively and at postoperative day 1 but lower in the restrictive group on day 2 (mean difference [MD], 7.0 g L −1; 95% confidence interval [CI], 1.6–12.4). Lowest haemoglobin within 30 days/before discharge was lower in the restrictive group (MD, 5.3 g L −1; 95% CI, 1.7–9.0). Overall, 58% of patients in the restrictive group received no transfusion compared with 4% in the liberal group (difference in proportion, 54.5%; 95% CI, 36.8–72.2). The proportion with the primary clinical outcome was 14/26 (54%, liberal) vs 24/34 (71%, restrictive), and the difference in proportion was –16.7% (95% CI, –41.3 to 7.8; P=0.18). ConclusionA clinical trial of two transfusion strategies in hip fracture with a clinically relevant cardiac outcome is feasible

Troponin in Acute chest pain to Risk stratify and Guide EffecTive use of Computed Tomography Coronary Angiography (TARGET-CTCA):A randomised controlled trial

Background: The majority of patients with suspected acute coronary syndrome presenting to the emergency department will be discharged once myocardial infarction has been ruled out, although a proportion will have unrecognised coronary artery disease. In this setting, high-sensitivity cardiac troponin identifies those at increased risk of future cardiac events. In patients with intermediate cardiac troponin concentrations in whom myocardial infarction has been ruled out, this trial aims to investigate whether outpatient computed tomography coronary angiography (CTCA) reduces subsequent myocardial infarction or cardiac death. Methods: TARGET-CTCA is a multicentre prospective randomised open label with blinded endpoint parallel group event driven trial. After myocardial infarction and clear alternative diagnoses have been ruled out, participants with intermediate cardiac troponin concentrations (5 ng/L to 99th centile upper reference limit) will be randomised 1:1 to outpatient CTCA plus standard of care or standard of care alone. The primary endpoint is myocardial infarction or cardiac death. Secondary endpoints include clinical, patient-centred, process and cost-effectiveness. Recruitment of 2270 patients will give 90% power with a two-sided P value of 0.05 to detect a 40% relative risk reduction in the primary endpoint. Follow-up will continue until 97 primary outcome events have been accrued in the standard care arm with an estimated median follow-up of 36 months. Discussion: This randomised controlled trial will determine whether high-sensitivity cardiac troponin-guided CTCA can improve outcomes and reduce subsequent major adverse cardiac events in patients presenting to the emergency department who do not have myocardial infarction. Trial registration: ClinicalTrials.gov Identifier: NCT03952351. Registered on May 16, 2019

A preoperative package of care for osteoarthritis, consisting of weight loss, orthotics, rehabilitation, topical and oral analgesia (OPPORTUNITY): A two centre open label randomised controlled feasibility trial

Background Osteoarthritis of the knee is a major cause of disability worldwide. Non-operative treatments can reduce the morbidity but adherence is poor. We hypothesised that adherence could be optimised if behavioural change was established in the preoperative period. Therefore, we aimed to assess feasibility, acceptability, and recruitment and retention rates of a preoperative package of non-operative care in patients awaiting knee replacement surgery. Methods We did an open-label, randomised controlled, feasibility trial in two secondary care centres in the UK. Eligible participants were aged 15–85 years, on the waiting list for a knee arthroplasty for osteoarthritis, and met at least one of the thresholds for one of the four components of the preoperative package of non-operative care intervention (ie, weight loss, exercise therapy, use of insoles, and analgesia adjustment). Participants were randomly assigned (2:1) to either the intervention group or the standard of care (ie, control) group. All four aspects of the intervention were delivered weekly over 12 weeks. Participants in the intervention group were reviewed regularly to assess adherence. The primary outcome was acceptability and feasibility of delivering the intervention, as measured by recruitment rate, retention rate at follow-up review after planned surgery, health-related quality of life, joint-specific scores, and adherence (weight change and qualitative interviews). This study is registered with ISRCTN, ISRCTN96684272. Findings Between Sept 3 2018, and Aug 30, 2019, we screened 233 patients, of whom 163 (73%) were excluded and 60 (27%) were randomly assigned to either the intervention group (n=40) or the control group (n=20). 34 (57%) of 60 participants were women, 26 (43%) were men, and the mean age was 66·8 years (SD 8·6). Uptake of the specific intervention components varied: 31 (78%) of 40 had exercise therapy, 28 (70%) weight loss, 22 (55%) analgesia adjustment, and insoles (18 [45%]). Overall median adherence was 94% (IQR 79·5–100). At the final review, the intervention group lost a mean of 11·2 kg (SD 5·6) compared with 1·3 kg (3·8) in the control group (estimated difference –9·8 kg [95% CI –13·4 to –6·3]). A clinically significant improvement in health-related quality o life (mean change 0·078 [SD 0·195]) were reported, and joint-specific scores showed greater improvement in the intervention group than in the control group. No adverse events attributable to the intervention occurred. Interpretation Participants adhered well to the non-operative interventions and their health-related quality of life improved. Participant and health professional feedback were extremely positive. These findings support progression to a full-scale effectiveness trial

Osteoarthritis Preoperative Package for care of Orthotics, Rehabilitation, Topical and oral agent Usage and Nutrition to Improve ouTcomes at a Year (OPPORTUNITY); a feasibility study protocol for a randomised controlled trial

BackgroundPatients’ pre-operative health and physical function is known to influence their post-operative outcomes. In patients with knee osteoarthritis, pharmacological and non-pharmacological options are often not optimised prior to joint replacement. This results in some patients undergoing surgery when they are not as fit as they could be. The aim of this study is to assess the feasibility and acceptability of a pre-operative package of non-operative care versus standard care prior to joint replacement.Methods/designThis is a multicentre, randomised controlled feasibility trial of patients undergoing primary total knee replacement for osteoarthritis. Sixty patients will be recruited and randomised (2:1) to intervention or standard care arms. Data will be collected at baseline (before the start of the intervention), around the end of the intervention period and a minimum of 90 days after the planned date of surgery. Adherence will be reviewed each week during the intervention period (by telephone or in person). Participants will be randomised to a pre-operative package of non-operative care or standard care. The non-operative care will consist of (1) a weight-loss programme, (2) a set of exercises, (3) provision of advice on analgesia use and (4) provision of insoles. The intervention will be started as soon as possible after patients have been added to the waiting list for joint replacement surgery to take advantage of the incentive for behavioural change that this will create. The primary outcomes of this study are feasibility outcomes which will indicate whether the intervention and study protocol is feasible and acceptable and whether a full-scale effectiveness trial is warranted.The following will be measured and used to inform study feasibility: rate of recruitment, rate of retention at 90-day follow-up review after planned surgery date, and adherence to the intervention estimated through review questionnaires and weight change (for those receiving the weight-loss aspect of intervention). In addition the following information will be assessed qualitatively: analysis of qualitative interviews exploring acceptability, feasibility, adherence and possible barriers to implementing the intervention, and acceptability of the different outcome measures.DiscussionThe aims of the study specifically relate to testing the feasibility and acceptability of the proposed effectiveness trial intervention and the feasibility of the trial methods.This study forms the important first step in developing and assessing whether the intervention has the potential to be assessed in a future fully powered effectiveness trial. The findings will also be used to refine the design of the effectiveness trial.Trial registrationISRCTN registry, ID: ISRCTN96684272. Registered on 18 April 2018