Room for Improvement in Conducting and Reporting Non-Inferiority Randomized Controlled Trials on Drugs: A Systematic Review

BACKGROUND: A non-inferiority (NI) trial is intended to show that the effect of a new treatment is not worse than the comparator. We conducted a review to identify how NI trials were conducted and reported, and whether the standard requirements from the guidelines were followed. METHODOLOGY AND PRINCIPAL FINDINGS: From 300 randomly selected articles on NI trials registered in PubMed at 5 February 2009, we included 227 NI articles that referred to 232 trials. We excluded studies on bioequivalence, trials on healthy volunteers, non-drug trials, and articles of which the full-text version could not be retrieved. A large proportion of trials (34.0%) did not use blinding. The NI margin was reported in 97.8% of the trials, but only 45.7% of the trials reported the method to determine the margin. Most of the trials used either intention to treat (ITT) (34.9%) or per-protocol (PP) analysis (19.4%), while 41.8% of the trials used both methods. Less than 10% of the trials included a placebo arm to confirm the efficacy of the new drug and active comparator against placebo, and less than 5.0% were reporting the similarity of the current trial with the previous comparator's trials. In general, no difference was seen in the quality of reporting before and after the release of the CONSORT statement extension 2006 or between the high-impact and low-impact journals. CONCLUSION: The conduct and reporting of NI trials can be improved, particularly in terms of maximizing the use of blinding, the use of both ITT and PP analysis, reporting the similarity with the previous comparator's trials to guarantee a valid constancy assumption, and most importantly reporting the method to determine the NI margin

Some considerations in the design and interpretation of antimalarial drug trials in uncomplicated falciparum malaria

BACKGROUND: Treatments for uncomplicated falciparum malaria should have high cure rates. The World Health Organization has recently set a target cure rate of 95% assessed at 28 days. The use of more effective drugs, with longer periods of patient follow-up, and parasite genotyping to distinguish recrudescence from reinfection raise issues related to the design and interpretation of antimalarial treatment trials in uncomplicated falciparum malaria which are discussed here. METHODS: The importance of adequate follow-up is presented and the advantages and disadvantages of non-inferiority trials are discussed. The different methods of interpreting trial results are described, and the difficulties created by loss to follow-up and missing or indeterminate genotyping results are reviewed. CONCLUSION: To characterize cure rates adequately assessment of antimalarial drug efficacy in uncomplicated malaria requires a minimum of 28 days and as much as 63 days follow-up after starting treatment. The longer the duration of follow-up in community-based assessments, the greater is the risk that this will be incomplete, and in endemic areas, the greater is the probability of reinfection. Recrudescence can be distinguished from reinfection using PCR genotyping but there are commonly missing or indeterminate results. There is no consensus on how these data should be analysed, and so a variety of approaches have been employed. It is argued that the correct approach to analysing antimalarial drug efficacy assessments is survival analysis, and patients with missing or indeterminate PCR results should either be censored from the analysis, or if there are sufficient data, results should be adjusted based on the identified ratio of new infections to recrudescences at the time of recurrent parasitaemia. Where the estimated cure rates with currently recommended treatments exceed 95%, individual comparisons with new regimens should generally be designed as non-inferiority trials with sample sizes sufficient to determine adequate precision of cure rate estimates (such that the lower 95% confidence interval bound exceeds 90%)

Methodological standards in non-inferiority AIDS trials: moving from adherence to compliance

BACKGROUND: The interpretation of the results of active-control trials regarding the efficacy and safety of a new drug is important for drug registration and following clinical use. It has been suggested that non-inferiority and equivalence studies are not reported with the same quantitative rigor as superiority studies. METHODS: Standard methodological criteria for non-inferiority and equivalence trials including design, analysis and interpretation issues were applied to 18 recently conducted large non-inferiority (15) and equivalence (3) randomized trials in the field of AIDS antiretroviral therapy. We used the continuity-corrected non-inferiority chi-square to test 95% confidence interval treatment difference against the predefined non-inferiority margin. RESULTS: The pre-specified non-inferiority margin ranged from 10% to 15%. Only 4 studies provided justification for their choice. 39% of the studies (7/18) reported only intent-to-treat (ITT) analysis for the primary endpoint. When on-treatment (OT) and ITT statistical analyses were provided, ITT was favoured over OT for results interpretation for all but one study, inappropriately in this statistical context. All but two of the studies concluded there was "similar" efficacy of the experimental group. However, 9/18 had inconclusive results for non-inferiority. CONCLUSION: Conclusions about non-inferiority should be drawn on the basis of the confidence interval analysis of an appropriate primary endpoint, using the predefined criteria for non-inferiority, in both OT and ITT, in compliance with the non-inferiority and equivalence CONSORT statement. We suggest that the use of the non-inferiority chi-square test may provide additional useful information

Treatment of chronic back pain by sensory discrimination training. A Phase I RCT of a novel device (FairMed) vs. TENS

Background: The causes of chronic low back pain (CLBP) remain obscure and effective treatment of symptoms remains elusive. A mechanism of relieving chronic pain based on the consequences of conflicting unpleasant sensory inputs to the central nervous system has been hypothesised. As a result a device was generated to deliver sensory discrimination training (FairMed), and this randomised controlled trial compared therapeutic effects with a comparable treatment modality, TENS. Methods: 60 patients with CLBP were recruited from physiotherapy referrals to a single-blinded, randomised controlled, non-inferiority trial. They were randomised to receive either FairMed or TENS and asked to use the allocated device for 30 minutes, twice a day, for 3 weeks. The primary outcome variable measured at 0 and 3 weeks was pain intensity measured using a visual analogue scale averaged over 7 days. Secondary outcome measures were Oswestry Disability Index, 3 timed physical tests, 4 questionnaires assessing different aspects of emotional coping and a global measure of patient rating of change. Data were analysed for the difference in change of scores between groups using one-way ANOVA. Results: Baseline characteristics of the two groups were comparable. The primary outcome, change in pain intensity (VAS) at 3 weeks showed a mean difference between groups of -0.1, (non significant p = 0.82). The mean difference in change in ODI scores was 0.4; (non significant p = 0.85). Differences in change of physical functioning showed that no significant difference in change of scores for any of these test (p = 0.58 – 0.90). Changes in scores of aspects of emotional coping also demonstrated no significant difference in change scores between the groups (p = 0.14 – 0.94). Conclusion: FairMed was not inferior to TENS treatment. The findings have implications for further research on current chronic pain theories and treatments. Further work to explore these mechanisms is important to expand our understanding of chronic pain and the role of neuro-modulation

Probiotic prophylaxis in patients with predicted severe acute pancreatitis (PROPATRIA): design and rationale of a double-blind, placebo-controlled randomised multicenter trial [ISRCTN38327949]

BACKGROUND: Infectious complications are the major cause of death in acute pancreatitis. Small bowel bacterial overgrowth and subsequent bacterial translocation are held responsible for the vast majority of these infections. Goal of this study is to determine whether selected probiotics are capable of preventing infectious complications without the disadvantages of antibiotic prophylaxis; antibiotic resistance and fungal overgrowth. METHODS/DESIGN: PROPATRIA is a double-blind, placebo-controlled randomised multicenter trial in which 200 patients will be randomly allocated to a multispecies probiotic preparation (Ecologic 641) or placebo. The study is performed in all 8 Dutch University Hospitals and 7 non-University hospitals. The study-product is administered twice daily through a nasojejunal tube for 28 days or until discharge. Patients eligible for randomisation are adult patients with a first onset of predicted severe acute pancreatitis: Imrie criteria 3 or more, CRP 150 mg/L or more, APACHE II score 8 or more. Exclusion criteria are post-ERCP pancreatitis, malignancy, infection/sepsis caused by a second disease, intra-operative diagnosis of pancreatitis and use of probiotics during the study. Administration of the study product is started within 72 hours after onset of abdominal pain. The primary endpoint is the total number of infectious complications. Secondary endpoints are mortality, necrosectomy, antibiotic resistance, hospital stay and adverse events. To demonstrate that probiotic prophylaxis reduces the proportion of patients with infectious complications from 50% to 30%, with alpha 0,05 and power 80%, a total sample size of 200 patients was calculated. CONCLUSION: The PROPATRIA study is aimed to show a reduction in infectious complications due to early enteral use of multispecies probiotics in severe acute pancreatitis

Task shifting in maternal and newborn care: a non-inferiority study examining delegation of antenatal counseling to lay nurse aides supported by job aids in Benin

<p>Abstract</p> <p>Background</p> <p>Shifting the role of counseling to less skilled workers may improve efficiency and coverage of health services, but evidence is needed on the impact of substitution on quality of care. This research explored the influence of delegating maternal and newborn counseling responsibilities to clinic-based lay nurse aides on the quality of counseling provided as part of a task shifting initiative to expand their role.</p> <p>Methods</p> <p>Nurse-midwives and lay nurse aides in seven public maternities were trained to use job aids to improve counseling in maternal and newborn care. Quality of counseling and maternal knowledge were assessed using direct observation of antenatal consultations and patient exit interviews. Both provider types were interviewed to examine perceptions regarding the task shift. To compare provider performance levels, non-inferiority analyses were conducted where non-inferiority was demonstrated if the lower confidence limit of the performance difference did not exceed a margin of 10 percentage points.</p> <p>Results</p> <p>Mean percent of recommended messages provided by lay nurse aides was non-inferior to counseling by nurse-midwives in adjusted analyses for birth preparedness (β = -0.0, 95% CI: -9.0, 9.1), danger sign recognition (β = 4.7, 95% CI: -5.1, 14.6), and clean delivery (β = 1.4, 95% CI: -9.4, 12.3). Lay nurse aides demonstrated superior performance for communication on general prenatal care (β = 15.7, 95% CI: 7.0, 24.4), although non-inferiority was not achieved for newborn care counseling (β = -7.3, 95% CI: -23.1, 8.4). The proportion of women with correct knowledge was significantly higher among those counseled by lay nurse aides as compared to nurse-midwives in general prenatal care (β = 23.8, 95% CI: 15.7, 32.0), birth preparedness (β = 12.7, 95% CI: 5.2, 20.1), and danger sign recognition (β = 8.6, 95% CI: 3.3, 13.9). Both cadres had positive opinions regarding task shifting, although several preferred 'task sharing' over full delegation.</p> <p>Conclusions</p> <p>Lay nurse aides can provide effective antenatal counseling in maternal and newborn care in facility-based settings, provided they receive adequate training and support. Efforts are needed to improve management of human resources to ensure that effective mechanisms for regulating and financing task shifting are sustained.</p

INVESTIGATE-I (INVasive Evaluation before Surgical Treatment of Incontinence Gives Added Therapeutic Effect?): study protocol for a mixed methods study to assess the feasibility of a future randomised controlled trial of the clinical utility of invasive urodynamic testing

<p>Abstract</p> <p>Background</p> <p>Urinary incontinence is an important health problem to the individual sufferer and to health services. Stress and stress predominant mixed urinary incontinence are increasingly managed by surgery due to advances in surgical techniques. Despite the lack of evidence for its clinical utility, most clinicians undertake invasive urodynamic testing (IUT) to confirm a functional diagnosis of urodynamic stress incontinence before offering surgery for this condition. IUT is expensive, embarrassing and uncomfortable for women and carries a small risk. Recent systematic reviews have confirmed the lack of high quality evidence of effectiveness.</p> <p>The aim of this pilot study is to test the feasibility of a future definitive randomised control trial that would address whether IUT alters treatment decisions and treatment outcome in these women and would test its clinical and cost effectiveness.</p> <p>Methods/design</p> <p>This is a mixed methods pragmatic multicentre feasibility pilot study with four components:-</p> <p>(a) A multicentre, external pilot randomised trial comparing basic clinical assessment with non-invasive tests and IUT. The outcome measures are rates of recruitment, randomisation and data completion. Data will be used to estimate sample size necessary for the definitive trial.</p> <p>(b) Qualitative interviews of a purposively sampled sub-set of women eligible for the pilot trial will explore willingness to participate, be randomised and their overall trial experience.</p> <p>(c) A national survey of clinicians to determine their views of IUT in this context, the main outcome being their willingness to randomise patients into the definitive trial.</p> <p>(d) Qualitative interviews of a purposively sampled group of these clinicians will explore whether and how they use IUT to inform their decisions.</p> <p>Discussion</p> <p>The pilot trial will provide evidence of feasibility and acceptability and therefore inform the decision whether to proceed to the definitive trial. Results will inform the design and conduct of the definitive trial and ensure its effectiveness in achieving its research aim.</p> <p>Trial registration number</p> <p>Current Controlled Trials <a href="http://www.controlled-trials.com/ISRCTN71327395">ISRCTN71327395</a> assigned 7^thJune 2010.</p

Equivalence and noninferiority trials – are they viable alternatives for registration of new drugs? (III)

The scientific community's reliance on active-controlled trials is steadily increasing, as widespread agreement emerges concerning the role of these trials as viable alternatives to placebo trials. These trials present substantial challenges with regard to design and interpretation as their complexity increases, and the potential need for larger sample sizes impacts the cost and time variables of the drug development process. The potential efficacy and safety benefits derived from these trials may never be demonstrated by other methods. Active-controlled trials can develop valuable data to inform both prescribers and patients about the dose- and time-dependent actions of any new drug and can contribute to the management and communication of risks associated with the relevant therapeutic products

TEAM-UP for quality: a cluster randomized controlled trial protocol focused on preventing pressure ulcers through repositioning frequency and precipitating factors

Background: Pressure ulcers/injuries (PrUs), a critical concern for nursing homes (NH), are responsible for chronic wounds, amputations, septic infections, and premature deaths. PrUs occur most commonly in older adults and NH residence is a risk factor for their development, with at least one of every nine U.S. NH residents experiencing a PrU and many NHs having high incidence and prevalence rates, in some instances well over 20%. PrU direct treatment costs are greater than prevention costs, making prevention-focused protocols critical. Current PrU prevention protocols recommend repositioning residents at moderate, high, and severe risk every 2 h. The advent of visco- elastic (VE) high-density foam support-surfaces over the past decade may now make it possible to extend the repositioning interval to every 3 or 4 h without increasing PrU development. The TEAM-UP (Turn Everyone And Move for Ulcer Prevention) study aims to determine: 1) whether repositioning interval can be extended for NH residents without compromising PrU incidence and 2) how changes in medical severity interact with changes in risk level and repositioning schedule to predict PrU development. Methods: In this proposed cluster randomized study, 9 NHs will be randomly assigned to one of three repositioning intervals (2, 3, or 4 h) for a 4-week period. Each enrolled site will use a single NH-wide repositioning interval as the standard of care for residents at low, moderate, and high risk of PrU development (N = 951) meeting the following criteria: minimum 3-day stay, without PrUs, no adhesive allergy, and using VE support surfaces (mattresses). An FDA-cleared patient monitoring system that records position/movement of these residents via individual wireless sensors will be used to visually cue staff when residents need repositioning and document compliance with repositioning protocols. Discussion: This study will advance knowledge about repositioning frequency and clinically assessed PrU risk level in relation to PrU incidence and medical severity. Outcomes of this research will contribute to future guidelines for more precise preventive nursing practices and refinement of PrU prevention guidelines. Trial registration: Clinical Trial Registration: NCT02996331