The tyranny of non-inferiority trials.

Opportunities to decrease the toxicity and cost of approved treatment regimens with lower dose, less frequent, or shorter duration alternative regimens have been limited by the perception that alternatives must be non-inferior to approved regimens. Non-inferiority trials are large and expensive to do, because they must show statistically that the alternative and approved therapies differ in a single outcome, by a margin far smaller than that required to demonstrate superiority. Non-inferiority's flaws are manifest: it ignores variability expected to occur with repeated evaluation of the approved therapy, fails to recognise that a trial of similar design will be labelled as superiority or non-inferiority depending on whether it is done prior to or after initial registration of the approved treatment, and relegates endpoints such as toxicity and cost. For example, while a less toxic and less costly regimen of 3 months duration would typically be required to demonstrate efficacy that is non-inferior to that of a standard regimen of 6 months to displace it, the longer duration therapy has no such obligation to prove its superiority. This situation is the tyranny of the non-inferiority trial: its statistics perpetuate less cost-effective regimens, which are not patient-centred, even when less intensive therapies confer survival benefits nearly identical to those of the standard, by placing a disproportionately large burden of proof on the alternative. This approach is illogical. We propose that the designation of trials as superiority or non-inferiority be abandoned, and that randomised, controlled trials should henceforth be described simply as "comparative".

Evaluating the effectiveness of a multi-component lifestyle therapy program versus psychological therapy for managing mood disorders (HARMON-E): protocol of a randomised non-inferiority trial.

BACKGROUND: Mood disorders, including unipolar and bipolar depression, contribute significantly to the global burden of disease. Psychological therapy is considered a gold standard non-pharmacological treatment for managing these conditions; however, a growing body of evidence also supports the use of lifestyle therapies for these conditions. Despite some clinical guidelines endorsing the application of lifestyle therapies as a first-line treatment for individuals with mood disorders, there is limited evidence that this recommendation has been widely adopted into routine practice. A key obstacle is the insufficient evidence on whether lifestyle therapies match the clinical and cost effectiveness of psychological therapy, particularly for treating those with moderate to severe symptoms. The HARMON-E Trial seeks to address this gap by conducting a non-inferiority trial evaluating whether a multi-component lifestyle therapy program is non-inferior to psychological therapy on clinical and cost-effectiveness outcomes over 8-weeks for adults with major depressive disorder and bipolar affective disorder. METHODS: This trial uses an individually randomised group treatment design with computer generated block randomisation (1:1). Three hundred and seventy-eight adults with clinical depression or bipolar affective disorder, a recent major depressive episode, and moderate-to-severe depressive symptoms are randomised to receive either lifestyle therapy or psychological therapy (adjunctive to any existing treatments, including pharmacotherapies). Both therapy programs are delivered remotely, via a secure online video conferencing platform. The programs comprise an individual session and six subsequent group-based sessions over 8-weeks. All program aspects (e.g. session duration, time of day, and communications between participants and facilitators) are matched except for the content and program facilitators. Lifestyle therapy is provided by a dietitian and exercise physiologist focusing on four pillars of lifestyle (diet, physical activity, sleep, and substance use), and the psychological therapy program is provided by two psychologists using a cognitive behavioural therapy approach. Data collection occurs at baseline, 8-weeks, 16-weeks, and 6 months with research assistants blinded to allocation. The primary outcome is depressive symptoms at 8 weeks, measured using the Montgomery-Åsberg Depression Rating Scale (MADRS) (minimal clinically important difference = 1.6). A pre-specified within-trial economic evaluation will also be conducted. DISCUSSION: Should lifestyle therapy be found to be as clinically and cost effective as psychological therapy for managing mood disorders, this approach has potential to be considered as an adjunctive treatment for those with moderate to severe depressive symptoms. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12622001026718, registered 22nd July 2022. PROTOCOL VERSION:  4.14, 26/06/2024.

A randomized controlled non-inferiority trial of placebo versus macrolide antibiotics for Mycoplasma pneumoniae infection in children with community-acquired pneumonia: trial protocol for the MYTHIC Study.

BACKGROUND: Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in school-aged children. Macrolides are the first-line treatment for this infection. However, it is unclear whether macrolides are effective in treating M. pneumoniae CAP, mainly due to limitations in microbiological diagnosis of previous studies. The extensive global use of macrolides has led to increasing antimicrobial resistance. The overall objective of this trial is to produce efficacy data for macrolide treatment in children with M. pneumoniae CAP. METHODS: The MYTHIC Study is a randomized, double-blind, placebo-controlled, multicenter, non-inferiority trial in 13 Swiss pediatric centers. Previously healthy ambulatory and hospitalized children aged 3-17 years with clinically diagnosed CAP will be screened with a sensitive and commercially available M. pneumoniae-specific IgM lateral flow assay from capillary blood. Mycoplasma pneumoniae infection in screened patients will be verified retrospectively by respiratory PCR (reference test) and IgM antibody-secreting cell enzyme-linked immunospot (ELISpot) assay (confirmatory test for distinguishing between carriage and infection). Patients will be randomized 1:1 to receive a 5-day treatment of macrolides (azithromycin) or placebo. The co-primary endpoints are (1) time to normalization of all vital signs, including body temperature, respiratory rate, heart rate, and saturation of peripheral oxygen (efficacy), and (2) CAP-related change in patient care status (i.e., admission, re-admission, or intensive care unit transfer) within 28 days (safety). Secondary outcomes include adverse events (AEs), as well as antimicrobial and anti-inflammatory effects. For both co-primary endpoints, we aim to show non-inferiority of placebo compared to macrolide treatment. We expect no macrolide effect (hazard ratio of 1, absolute risk difference of 0) and set the corresponding non-inferiority margins to 0.7 and -7.5%. The "at least one" success criterion is used to handle multiplicity with the two co-primary endpoints. With a power of 80% to reject at least one null hypothesis at a one-sided significance level of 1.25%, 376 patients will be required. DISCUSSION: This trial will produce efficacy data for macrolide treatment in children with M. pneumoniae CAP that might help to reduce the prescription of antibiotics and therefore contribute to the global efforts toward reducing antimicrobial resistance. TRIAL REGISTRATION: ClinicalTrials.gov, NCT06325293. Registered on 24 April 2024.

Remote monitoring of rheumatoid arthritis (REMORA): study protocol for a stepped wedge cluster randomized trial and process evaluation of an integrated symptom tracking intervention.

BACKGROUND: Management of rheumatoid arthritis (RA) relies on symptoms reported by patients during infrequent outpatient clinic visits. These reports are often incomplete and inaccurate due to poor recall, leading to suboptimal treatment decisions and outcomes. Asking people to track symptoms in-between visits and integrating the data into clinical pathways may improve this. However, knowledge on how to implement this into practice and its impact on services and outcomes remains scarce in RA. Therefore, we evaluate the comparative effectiveness and cost-effectiveness of integrated symptom tracking in people with RA over and above usual care, while generating insights on factors for successful implementation. METHODS: In this superiority stepped wedge cluster-randomized controlled trial with continuous recruitment short exposure design, 16 rheumatology outpatient departments (clusters) recruit a total of 732 people with active RA. They initially offer clinic visits according to standard of care before switching in pairs to visits with integrated symptom tracking. Clusters switch in randomized order every 3 weeks. Integrated symptom tracking consists of (1) a mobile app for patients to track their symptoms daily and other RA aspects weekly/monthly, and (2) an interactive dashboard visualizing the app data, which healthcare professionals access from their electronic health record system. Clinic visits happen according to usual practice, with tracked symptom data only reviewed during visits. Our primary outcome is a difference in marginal mean disease activity score at 12 ± 3 months between standard of care and integrated symptom tracking, after accounting for baseline values, cluster, and other covariates. Secondary outcomes include patient-reported disease activity, quality of life and quality-adjusted life-years, medication/resource use, consultation and decision-making experience, self-management, and illness perception. We also conduct interviews and observations as part of a parallel process evaluation to gather information on implementation. DISCUSSION: Our trial will generate high-quality evidence of comparative and cost-effectiveness of integrated symptom tracking compared to standard of care in people with RA, with our process evaluation delivering knowledge on successful implementation. This optimizes the chances of integrated symptom tracking being adopted more widely if we find it is (cost-) effective. TRIAL REGISTRATION: Registered 4-Jun-2024 on https://www.isrctn.com/ , ISRCTN51539448. TRIAL OPEN SCIENCE FRAMEWORK REPOSITORY: https://osf.io/sj9ha/ .

Treat-to-target fixed dose rituximab retreatment versus fixed interval retreatment with disease activity-guided rituximab dose optimisation for patients with rheumatoid arthritis: study protocol for a multicentre randomised controlled superiority trial focusing on long-term disease impact (RITUXERA).

BACKGROUND: The optimal retreatment strategy with rituximab for rheumatoid arthritis (RA) remains a point of discussion. Depending on local guidelines, rituximab can either be administered at fixed intervals or when losing disease control, balancing therapeutic effectiveness with drug overexposure. However, treatment based on loss of disease control may significantly affect patients' lives, provoking uncertainty and potentially leading to progressive joint damage. Moreover, as low-dose rituximab proved to be effective in treating RA while decreasing toxicity, drug exposure may be limited by tapering down rituximab doses guided by disease activity. METHODS: RITUXERA is a 104-week open-label multicentre randomised controlled superiority trial. In total, 134 patients with RA treated with rituximab will be 1:1 randomised when in need of retreatment (DAS28-CRP ≥ 3.2 with previous rituximab administration at least 24 weeks earlier) to either a treat-to-target-driven fixed dose retreatment strategy (usual care group) or fixed interval disease-activity guided dose optimisation strategy (experimental group). The usual care group will be retreated with fixed rituximab doses (1 × 1000 mg IV) in case of loss of disease control (DAS28-CRP ≥ 3.2). The experimental group will receive a 24-weekly rituximab treatment while tapering down the dose in a decreasing sequence if DAS28-CRP ≤ 3.2: 1 × 1000 mg IV (maximal dose), 1 × 500 mg IV, and 1 × 200 mg IV (minimal dose). If DAS28-CRP exceeds 3.2 at the six-monthly retreatment, patients will receive and remain on the previous effective dose. Study visits are planned every 12 weeks. Primary outcome is the comparison of longitudinal patient-reported disease impact over 104 weeks, measured with the Rheumatoid Arthritis Impact of Disease (RAID) instrument, analysed using a linear mixed model. Main secondary outcome is the comparison of longitudinal disease activity (DAS28-CRP) over 104 weeks. DISCUSSION: The RITUXERA trial aims to explore the optimal retreatment strategy with rituximab for RA in terms of long-term patient-reported disease impact, by proposing a fixed interval disease activity-guided dose optimisation strategy as compared to a treat-to-target fixed dose strategy. TRIAL REGISTRATION: CTIS 2023-506638-59-01 (registration date: 07 September 2023), ClinicalTrials.gov NCT06003283 (registration date: 17 August 2023).

Artificial intelligence-based CT-free quantitative thyroid SPECT for thyrotoxicosis: study protocol of a multicentre, prospective, non-inferiority study.

INTRODUCTION: Technetium thyroid uptake (TcTU) measured by single-photon emission CT/CT (SPECT/CT) is an important diagnostic tool for the differential diagnosis of Graves' disease and destructive thyroiditis. Artificial intelligence (AI) may reduce CT-induced radiation exposure by substituting the role of CT in attenuation correction (AC) and thyroid segmentation, thus realising CT-free SPECT. This study aims to compare the diagnostic accuracy for the differential diagnosis of thyrotoxicosis between CT-free SPECT and SPECT/CT. METHODS AND ANALYSIS: The AI-based CT-free SPECT is a single-blind, multicentre, prospective, non-inferiority, clinical trial with a paired design conducted in the Republic of Korea. Eligible participants are adult (≥19 years old) thyrotoxicosis patients without a previous history of hyperthyroidism or hypothyroidism. Approximately 160 subjects will be screened for quantitative thyroid SPECT/CT using Tc-99m pertechnetate. CT-free thyroid SPECT will be realised using only SPECT data by the trained convolutional neural networks. TcTU will be calculated by SPECT/CT and CT-free SPECT in each subject. The primary endpoint is the accuracy of diagnosing Graves' disease using TcTU. The trial will continue until 152 completed datasets have been enrolled to assess whether the 95% (two-sided) lower confidence limit of the accuracy difference (CT-free SPECT accuracy-SPECT/CT accuracy) for Graves' disease is greater than -0.1. The secondary endpoints include the accuracy of diagnosing destructive thyroiditis and predicting the need for antithyroid drug prescription within 1 month of the SPECT/CT. ETHICS AND DISSEMINATION: The study protocol has been approved by the institutional review board of Seoul National University Bundang Hospital (IRB No. B-2304-824-301), Konkuk University Medical Center (IRB No. 2023-05-022-006) and Chonnam National University Hospital (IRB No. CNUH-2023-108). Findings will be disseminated as reports, presentations and peer-reviewed journal articles. TRIAL REGISTRATION NUMBER: KCT0008387, Clinical Research Information Service of the Republic of Korea (CRIS).

Unilateral biportal endoscopic versus microscopic transforaminal lumbar interbody fusion for degenerative lumbar spinal stenosis in China: study protocol for a prospective, randomised, controlled, non-inferiority trial.

INTRODUCTION: Degenerative lumbar spinal stenosis is a common cause of low back or leg pain and disability in the elderly population. Patients with spinal stenosis who fail to respond to conservative treatment often require surgical interventions. Minimally invasive transforaminal lumbar interbody fusion (TLIF) with microscopic tubular technique (MT-TLIF) is a well-established procedure for lumbar spinal stenosis. Recently, a novel MIS technique, unilateral biportal endoscopic TLIF (UBE-TLIF), has been frequently performed to treat spinal stenosis. However, the efficacy and safety of using UBE-TLIF in this population have not been well examined. METHODS AND ANALYSIS: A total of 96 patients with lumbar spinal stenosis will be randomly assigned to the UBE-TLIF group or the MT-TLIF group at a 1:1 ratio to receive UBE-TLIF or MT-TLIF treatment respectively. The primary outcome is the Oswestry Disability Index (ODI) score at 1 year after receiving the surgery. Secondary outcomes include the ODI scores at additional time points, Visual Analogue Scale score, 36-Item Short Form Survey questionnaire, EuroQol 5 Dimensions questionnaire, radiological measurements (disc height, lumbar lordosis angles and vertebral fusion rate) and general condition during hospitalisation. ETHICS AND DISSEMINATION: This protocol is approved by the Medical Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University. All participants of the study will be well informed and written informed consent will be requested. Findings from this trial will be published in peer-reviewed publications, specifically in orthopedic and spinal journals. The completion of this study will not only examine the use of UBE-TLIF in lumbar spinal stenosis but also provide helpful clinical references. TRIAL REGISTRATION NUMBER: ChiCTR2300069333.

Impact of increasing post-filter ionised calcium target on regional citrate anticoagulation efficacy in ICU continuous renal replacement therapy: the non-inferiority randomised controlled Ca-CIBLE protocol.

INTRODUCTION: Continuous renal replacement therapy (CRRT) is a critical therapeutic intervention for patients with severe acute kidney injury in intensive care. However, premature filter clotting remains a significant challenge during CRRT, impacting treatment efficacy, costs and patient outcomes. Anticoagulation is essential to maintain circuit patency, with regional citrate anticoagulation (RCA) emerging as a preferred strategy due to its favourable bleeding profile. The standard target for post-filter ionised calcium (iCa) concentration during RCA-CRRT is set between 0.25 and 0.35 mmol/L, although evidence supporting this range is limited. We hypothesise that a higher post-filter iCa target (0.35-0.45 mmol/L) can provide comparable circuit patency while potentially reducing adverse effects associated with citrate administration. METHODS AND ANALYSIS: This multicentre randomised controlled non-inferiority trial will compare a low post-filter iCa target (0.25-0.35 mmol/L) with a higher post-filter iCa target (0.35-0.45 mmol/L) in patients undergoing RCA-CRRT in the intensive care unit. A total of 412 CRRT sessions will be randomised with a 1:1 ratio into these two groups. The primary outcome is the incidence of filter clotting. Secondary outcomes include filter lifespan, post-filter iCa levels, citrate infusion rates, the occurrence of metabolic adverse effects, financial costs and blood loss. ETHICS AND DISSEMINATION: The study has obtained approval from the ethics committee (Ethics Committee Est III, Nancy, France) and patients will be included after providing informed consent. The results will be disseminated at academic conferences and in peer-reviewed publications. All procedures were developed in order to assure data protection and confidentiality. TRIAL REGISTRATION NUMBER: NCT05814341.

SAME day amBulatory c (SAMBA): a multicenter, prospective, randomized clinical trial protocol.

BACKGROUND: A recent meta-analysis concluded that outpatient appendectomy appears feasible and safe, but there is a lack of high-quality evidence and a randomized trial is needed. The aim of this trial is to demonstrate that outpatient appendectomy is non-inferior to conventional inpatient appendectomy in terms of overall morbi-mortality on the 30th postoperative day (D30). METHODS: SAMBA is a prospective, randomized, controlled, multicenter non-inferiority trial. We will include 1400 patients admitted to 15 French hospitals between January 2023 and June 2025. Inclusion criteria are patients aged between 15 and 74 years presenting acute uncomplicated appendicitis suitable to be operated by laparoscopy. Patients will be randomized to receive outpatient care (day-surgery) or conventional inpatient care with overnight hospitalization in the surgery department. The primary outcome is postoperative morbi-mortality at D30. Secondary outcomes include time from diagnosis to appendectomy, length of total hospital stay, re-hospitalization, interventional radiology, re-interventions until D30, conversion from outpatient to inpatient, and quality of life and patient satisfaction using validated questionnaires. DISCUSSION: The SAMBA trial tests the hypothesis that outpatient surgery (i.e., without an overnight hospital stay) of uncomplicated acute appendicitis is a feasible and reliable procedure in establishments with a technical platform able to support this management strategy. TRIAL REGISTRATION: ClinicalTrials.gov NCT05691348. Registered on 20 January 2023.

Breaking the cycle of reoccurring low back pain with integrated motivational interviewing and cognitive behavioural therapy to facilitate education and exercise advice: a superiority randomised controlled trial study protocol.

BACKGROUND: Non-specific low back pain is a common and costly global issue. Many people with low back pain live for years with ongoing symptom recurrence and disability, making it crucial to find effective prevention strategies. Motivational interviewing (MI) is an evidence-based patient-centred counselling style that helps motivate individuals to change their behaviours. In combination, MI and cognitive-behavioural therapy (MI-CBT) has the potential to yield long term improvements in pain and disability and reduce incidence of recurrence. METHOD: This is a two-arm superiority randomised controlled trial comparing MI-CBT and Education (n = 83) with Education only (n = 83). Participants that have recovered from a recent episode of non-specific low back pain (7th consecutive day with pain ≤ 2 on a 0-10 numeric pain rating scale) will be eligible for inclusion into the study. Both groups will receive five 30-min sessions over a 10-week period as well as the Navigating Pain booklet, homework book and a standardised exercise programme. In the intervention group, MI-CBT techniques will be used to provide individualised support, identify beliefs, and increase engagement with the resources provided. Outcomes measures include pain (current and in the last 7 days) as rated on the numeric pain rating scale. This will be used to determine recurrence (number of participants who report back pain ≥ 3 out of 10 on the numeric pain rating scale). Furthermore, self-reported (1) pain intensity; (2) pain catastrophizing; (3) fear-avoidance beliefs; (4) pain self-efficacy; (5) depression and anxiety; (6) disability will be measured. All outcomes will be measured at baseline, and again at 3-, 6-, and 12-months post allocation. DISCUSSION: The effective delivery of self-management strategies to prevent recurrence of low back pain is an important aspect that requires urgent attention. This study will provide new information on the effectiveness of using an MI-CBT approach to facilitate self-management through education and exercise to improve low back pain outcomes. Evidence emerging from this trial has the potential to inform clinical practice and healthcare management of non-specific low back pain. TRIAL REGISTRATION: Prospectively registered with Australian New Zealand Clinical Trials Registry: ACTRN12623000746639 (10/07/2023).

A multi-center, double-blind, placebo-controlled, randomized, parallel-group, non-inferiority study to compare the efficacy of goal-directed tranexamic acid administration based on viscoelastic test versus preemptive tranexamic acid administration on postoperative bleeding in cardiovascular surgery (GDT trial).

BACKGROUND: Tranexamic acid (TXA) effectively attenuates hyperfibrinolysis and preemptive administration has been employed to reduce bleeding and blood transfusions in various surgical settings. However, TXA administration could be associated with adverse effects, such as seizures and thromboembolic risks. While patients with fibrinolysis shutdown showed greater thromboembolic complications and mortality, TXA administration may aggravate the degree of shutdown in these patients. Selective TXA administration based on the results of rotational thromboelastometry (ROTEM) would be non-inferior to preemptive TXA administration in reducing postoperative bleeding and beneficial in reducing its risks in patients undergoing cardiovascular surgery. METHODS: This non-inferiority, randomized, double-blind, placebo-controlled, multicenter trial will be performed in 3 tertiary university hospitals from August 2023 to March 2025. Seven hundred sixty-four patients undergoing cardiovascular surgery will be randomly allocated to get TXA as a preemptive (Group-P) or goal-directed strategy (Group-GDT) in each institution (with a 1:1 allocation ratio). After anesthesia induction, TXA (10 mg/kg and 2 mg/kg/h) and a placebo are administered after anesthesia induction in Group-P and Group-GDT, respectively. ROTEM tests are performed immediately before weaning from CPB and at the considerable bleeding post-CPB period. After getting the test results, a placebo is administered in Group-P (regardless of the test results). In Group-GDT, placebo or TXA is administered according to the results: placebo is administered if the amplitude at 10 min (A10-EXTEM) is ≥ 40 mm and lysis within 60 min (LI60-EXTEM) of EXTEM assay is ≥ 85%, or TXA (20 mg/kg) is administered if A10-EXTEM is < 40 mm or LI60-EXTEM is < 85%. The primary outcome is inter-group comparisons of postoperative bleeding (for 24 h). The secondary measures include comparisons of perioperative blood transfusion, coagulation profiles, reoperation, thromboembolic complications, seizures, in-hospital mortality, fibrinolysis phenotypes, and hospital costs. DISCUSSION: The absence of inter-group differences in postoperative bleeding would support the selective strategy's non-inferiority in reducing postoperative bleeding in these patients. The possible reduction in thromboembolic risks, seizures, and fibrinolysis shutdown in Group-GDT would support its superiority in reducing TXA-induced adverse events and the cost of their management. TRIAL REGISTRATION: This trial was registered at ClinicalTrials.gov with the registration number NCT05806346 on March 28, 2023. TRIAL STATUS: recruiting. Issue date: 2023 March 28 (by Tae-Yop Kim, MD, PhD). The trial was registered in the clinical registration on March 28, 2023 (ClinicalTrials.gov, NCT05806346) and revised to the latest version of its protocol (version no. 8, August 26, 2024) approved by the institutional review boards (IRBs) of all 3 university hospitals (Konkuk University Medical Center, 2023-07-005-001, Asan Medical Center, 2023-0248, and Samsung Medical Center, SMC 2023-06-048-002). Its recruitment was started on August 1, 2023, and will be completed on December 31, 2024. Protocol amendment number: 08 (protocol version 08, August 26, 2024). Revision chronology: 2023 March 28:Original. 2023 April 10:Amendment No 01. The primary reason for the amendment is the modification of Arms (adding one arm for sub-group analyses) and Interventions, Outcome Measures, Study Design, Study Description, Study Status, Eligibility, and Study Identification. 2023 May 03:Amendment No 02. The primary reason for the amendment is to modify the Outcome Measures and update the study status. 2023 July 06:Amendment No 03. The primary reason for amendment is to update the chronological study status. 2023 July 07:Amendment No 04. The primary reason for the amendment is the modification of study information (the treatment category was changed to diagnostic, and Phase 4 was changed to not applicable) and a chronological update on the study status. 2023 September 12:Amendment No 06. The primary reason for the amendment is a chronological update in the study status and the inclusion of additional information regarding contacts/locations and oversight. 2023 December 29:Amendment No 07. The primary reason for the amendment is to modify the outcome measures (including detailed information on outcome measures, addition of extra secondary measures, and chronological updates in study status). 2024 August 26:Amendment No 08. The primary reason for the amendment is to add detailed descriptions regarding data handling and the names and roles of the participating institutions and to update the chronological process of the trial.

Omentum preservation versus complete omentectomy in gastrectomy for gastric cancer (OMEGA trial): study protocol for a randomized controlled trial.

BACKGROUND: Potentially curative therapy for locally advanced gastric cancer consists of gastrectomy, usually in combination with perioperative chemotherapy. An oncological resection includes a radical (R0) gastrectomy and modified D2 lymphadenectomy; generally, a total omentectomy is also performed, to ensure the removal of possible microscopic disease. However, the omentum functions as a regulator of regional immune responses to prevent infections and prevents adhesions which could lead to bowel obstructions. Evidence supporting a survival benefit of routine complete omentectomy during gastrectomy is lacking. METHODS: OMEGA is a randomized controlled, open, parallel, non-inferiority, multicenter trial. Eligible patients are operable (ASA < 4) and have resectable (≦ cT4aN3bM0) primary gastric cancer. Patients will be 1:1 randomized between (sub)total gastrectomy with omentum preservation distal of the gastroepiploic vessels versus complete omentectomy. For a power of 80%, the target sample size is 654 patients. The primary objective is to investigate whether omentum preservation in gastrectomy for cancer is non-inferior to complete omentectomy in terms of 3-year overall survival. Secondary endpoints include intra- and postoperative outcomes, such as blood loss, operative time, hospital stay, readmission rate, quality of life, disease-free survival, and cost-effectiveness. DISCUSSION: The OMEGA trial investigates if omentum preservation during gastrectomy for gastric cancer is non-inferior to complete omentectomy in terms of 3-year overall survival, with non-inferiority being determined based on results from both the intention-to-treat and the per-protocol analyses. The OMEGA trial will elucidate whether routine complete omentectomy could be omitted, potentially reducing overtreatment. TRIAL REGISTRATION: ClinicalTrials.gov NCT05180864. Registered on 6th January 2022.

Non-inferiority, randomised, open-label clinical trial on the effectiveness of transurethral microwave thermotherapy compared to prostatic artery embolisation in reducing severe lower urinary tract symptoms in men with benign prostatic hyperplasia: study protocol for the TUMT-PAE-1 trial.

BACKGROUND: One-fourth of men older than 70 years have lower urinary tract symptoms (LUTS) that impair their quality of life. Transurethral resection of the prostate (TURP) is considered the gold standard for surgical treatment of LUTS caused by benign prostatic hyperplasia (BPH) that cannot be managed conservatively or pharmacologically. However, TURP is only an option for patients fit for surgery and can result in complications. Transurethral microwave thermotherapy (TUMT) and prostatic artery embolisation (PAE) are alternative minimally invasive surgical therapies (MISTs) performed in an outpatient setting. Both treatments have shown to reduce LUTS with a similar post-procedure outcome in mean International Prostate Symptom Score (IPSS). It is however still unknown if TUMT and PAE perform equally well as they have never been directly compared in a randomised clinical trial. The objective of this clinical trial is to assess if PAE is non-inferior to TUMT in reducing LUTS secondary to BPH. METHODS: This study is designed as a multicentre, non-inferiority, open-label randomised clinical trial. Patients will be randomised with a 1:1 allocation ratio between treatments. The primary outcome is the IPSS of the two arms after 6 months. The primary outcome will be evaluated using a 95% confidence interval against the predefined non-inferiority margin of + 3 points in IPSS. Secondary objectives include the comparison of patient-reported and functional outcomes at short- and long-term follow-up. We will follow the patients for 5 years to track long-term effect. Assuming a difference in mean IPSS after treatment of 1 point with an SD of 5 and a non-inferiority margin set at the threshold for a clinically non-meaningful difference of + 3 points, the calculated sample size was 100 patients per arm. To compensate for 10% dropout, the study will include 223 patients. DISCUSSION: In this first randomised clinical trial to compare two MISTs, we expect non-inferiority of PAE to TUMT. The most prominent problems with MIST BPH treatments are the unknown long-term effect and the lack of proper selection of candidates for a specific procedure. With analysis of the secondary outcomes, we aspire to contribute to a better understanding of durability and provide knowledge to guide treatment decisions. TRIAL REGISTRATION: ClinicalTrials.gov NCT05686525. Registered on January 17, 2023, https://clinicaltrials.gov/study/NCT05686525 .

3D printed versus milled stabilization splints for the management of bruxism and temporomandibular disorders: study protocol for a randomized prospective single-blinded crossover trial.

BACKGROUND: Nowadays, stabilization splints for the management of bruxism and temporomandibular disorders (TMD) can be produced utilizing a digital workflow comprising a digital impression of the teeth, digital splint design, and computer-aided manufacturing of the splints. The latter is usually a milling process, however, more recently 3D printing gained popularity due to its better cost and time efficiency. It remains unknown whether 3D printed stabilization splints are inferior to milled splints regarding clinical outcomes. METHODS: This clinical trial assesses the non-inferiority of 3D printed occlusal splints compared to milled occlusal splints in a monocentric prospective randomized single-blinded crossover trial with two cohorts. One cohort includes 20 participants with bruxism, the other 20 participants with pain-related TMD, i.e., myalgia, myofascial pain, or arthralgia of the jaw muscles/the temporomandibular joint(s) diagnosed according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Michigan-type stabilization splints are fabricated in a digital workflow by milling or 3D printing using CE-marked materials within their intended purpose. The participants wear a milled and a 3D printed splint in a randomized order for 3 months each, with follow-up visits after 2 weeks and 3 months. Investigated outcome parameters are oral health-related quality of life (OHRQoL) evaluated by the Oral Health Impact Profile (OHIP-G14), participant satisfaction as rated on a visual analog scale, therapeutic efficacy, and technical result of the splints. In this context, therapeutic efficacy means antagonist wear and-in the TMD group-reduction of pain/disability assessed by the Graded Chronic Pain Scale (GCPS v2.0) and clinical assessment following the DC/TMD standard, while technical outcome measures splint fit, wear and fracture rate. DISCUSSION: The trial will provide important information on the clinical outcome of 3D printed stabilization splints in comparison to milled splints and will, therefore, enable an evidence-based decision in favor of or against a manufacturing process. This, in turn, will guarantee for a maximum of the patient's OHRQoL during splint therapy, therapeutic efficacy, and longevity of the splints. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) DRKS00033904. Registered on March 15, 2024.

Electroacupuncture versus solifenacin succinate for female overactive bladder: study protocol for a multicentre, randomised, controlled, double-dummy, non-inferiority trial.

INTRODUCTION: Overactive bladder (OAB) affects approximately 500 million people worldwide, with a higher prevalence in women than in men, significantly impacting the quality of life of female patients. Treatment options for OAB are currently limited. Previous research has proposed that electroacupuncture could be a viable treatment for OAB in women, but there is a lack of high-quality clinical evidence. This study aims to evaluate the effectiveness of electroacupuncture as a safe and efficient non-pharmacological treatment for female OAB by comparing it with solifenacin succinate. METHODS AND ANALYSIS: This study is a multicentre, single-blind, double-dummy randomised controlled non-inferiority clinical trial involving 204 eligible female participants with OAB. Participants will be randomly assigned in a 1:1 ratio to either the electroacupuncture group (receiving electroacupuncture and placebo) or the solifenacin succinate group (receiving sham electroacupuncture and solifenacin succinate). Each participant will undergo 12 sessions of electroacupuncture (or sham electroacupuncture) treatment and solifenacin succinate (or placebo) treatment over a 4-week period. The primary outcome measure will be the percentage change in the number of micturition episodes every 24 hours at week 4 compared with baseline. Secondary outcomes will include a percentage reduction in the number of micturition episodes every 24 hours at 2th, 8th and 16th weeks of the trial, Overactive Bladder Symptom Score, number of urinary incontinence and urgency episodes every 24 hours based on a 3-day voiding diary, OAB Questionnaire, Generalised Anxiety Disorder Scale-7, King's Health Questionnaire and Participant Self-evaluation of Therapeutic Effects. Adverse events will be monitored throughout the study. Efficacy analyses will be conducted on both the intention-to-treat population and the per-protocol set population. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Medical Ethics Committee of Longhua Hospital Shanghai University of Traditional Chinese Medicine (approval number: 2022LCSY097). Each participant will sign a written informed consent before randomisation. The results of this study will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER : NCT05798403.

Omission of sentinel lymph node biopsy in patients with clinically axillary lymph node-negative early breast cancer (OMSLNB): protocol for a prospective, non-inferiority, single-arm, phase II clinical trial in China.

INTRODUCTION: Sentinel lymph node biopsy (SLNB) is a standard procedure for patients with clinically assessed negative axillary lymph nodes (cN0) during early-stage breast cancer (EBC). However, the majority of EBC patients have a negative pathological confirmation of the sentinel lymph node (SLN), and axillary surgery is inevitably associated with postoperative complications. Considering that SLNB has no therapeutic benefit, this trial aims to determine the safety of omitting SLNB in patients with cN0 early invasive breast cancer. METHODS AND ANALYSIS: The OMSLNB trial is a prospective, single-arm, non-inferiority, phase II, open-label study design involving female breast cancer patients with a tumor of ≤3 cm in diameter, who are considered axillary lymph-node-negative based on two or more radiological examinations, including axillary lymph node ultrasonography. Eligible patients will avoid axillary surgery but will undergo breast surgery, which is not limited to breast-conserving surgery. The trial begins in 2023 and is scheduled to end in 2027. The primary endpoint is 3 year invasive disease-free survival (iDFS). The secondary endpoints include the incidence of breast cancer-related lymphoedema, patient-reported outcomes, locoregional recurrence, local recurrence and regional recurrence. It is expected that the 3 year iDFS in patients undergoing SLNB is about 90%, combined with a non-inferiority cut-off of 5%, 80% power, 95% CIs, 0.05 test level, and 10% loss to follow-up rate, the planned enrollment is 311 patients. All enrolled patients will be included in the intention-to-treat analysis. ETHICS AND DISSEMINATION: This trial was approved by the Ethics Committee of the First Affiliated Hospital of Nanjing Medical University (No.2023-SR-193). All participants must provide written informed consent to be eligible. The protocol will be described in a peer-reviewed manuscript, and the results will be published in scientific journals and/or at academic conferences. TRIAL REGISTRATION NUMBER: NCT05935150.