A computer-aided detection system in the everyday setting of diagnostic, screening and surveillance colonoscopy: an international, randomized trial.

BACKGROUND AND STUDY AIM: Computer-aided detection (CADe) has been developed to improve detection during colonoscopy. After initial reports of high efficacy, there has been an increasing recognition of variability in the effectiveness of CADe systems. The aim of this study was to evaluate a CADe system (PENTAX Medical, Tokyo, Japan) in a varied colonoscopy population. PATIENTS AND METHODS: A multicenter, randomized trial was conducted at 7 hospitals (both university and non-university) in Europe and Canada. Participants referred for diagnostic, non-iFOBT screening, or surveillance colonoscopy were randomized (1:1) to undergo CADe-assisted or conventional colonoscopy (CC) by experienced endoscopists. Participants with insufficient bowel preparation were excluded from the analysis. Primary outcome was adenoma detection rate (ADR). Secondary outcomes included adenomas per colonoscopy (APC) and sessile serrated lesions per colonoscopy (SSLPC). RESULTS: In total, 581 participants were enrolled, of which 497 were included in the final analysis: 250 in the CADe-arm and 247 in the CC-arm. Surveillance was the indication in 202/497 (40.6%) colonoscopies, diagnostic in 199/497 (40.0%), and non-iFOBT screening in 96/497 (19.3%). Overall, ADR (38.4% vs. 37.7%; p=0.43) and APC (0.66 vs. 0.66; p=0.97) were similar between CADe and CC. SSLPC was increased (0.30 vs. 0.19; p=0.049) in the CADe-arm vs. CC. CONCLUSIONS: In this study conducted by experienced endoscopists, CADe did not result in a statistically significant increase in ADR. However, the ADR of our control group substantially surpassed our sample size assumptions, increasing the risk of an underpowered trial. (Trialsearch.who.int:NL9135).

Relative Efficacies of Interventions to Improve the Quality of Screening-Related Colonoscopy: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials.

BACKGROUND & AIMS: Significant variability exists in colonoscopy quality indicators, including adenoma detection rate (ADR). We synthesized evidence from randomized trials in a network meta-analysis on interventions to improve colonoscopy quality. METHODS: We included trials from database inceptions to September 25, 2023, of patients undergoing screening-related colonoscopy and presented efficacies of interventions within domains (periprocedural parameters, endoscopist-directed interventions, intraprocedural techniques, endoscopic technologies, distal attachment devices, and additive substances) compared to standard colonoscopy. The primary outcome was ADR. We used a Bayesian random-effects model using Markov-chain Monte Carlo simulation, with 10,000 burn-ins and 100,000 iterations. We calculated odds ratios with 95% credible intervals and present surface under the cumulative ranking (SUCRA) curves. RESULTS: We included 124 trials evaluating 37 interventions for the primary outcome. Nine interventions resulted in statistically significant improvements in ADR compared to standard colonoscopy (9-minute withdrawal time, dual observation, water exchange, iScan, linked color imaging, computer-aided detection, Endocuff, Endocuff Vision, and oral methylene blue). Dual observation (SUCRA, 0.84) and water exchange (SUCRA, 0.78) ranked highest among intraprocedural techniques; iScan (SUCRA, 0.95), linked color imaging (SUCRA, 0.85), and computer-aided detection (SUCRA, 0.78) among endoscopic technologies; WingCap (SUCRA, 0.87) and Endocuff (SUCRA, 0.85) among distal attachment devices and oral methylene blue (SUCRA, 0.94) among additive substances. No interventions improved detection of advanced adenomas, and only narrow-band imaging improved detection of serrated lesions (odds ratio, 2.94; 95% credible interval, 1.46-6.25). CONCLUSIONS: Several interventions are effective in improving adenoma detection and overall colonoscopy quality, many of which are cost-free. These results can inform endoscopists, unit managers, and endoscopy societies on relative efficacies.

Development and validation of a practical clinical risk prediction model for post-endoscopic retrograde cholangiopancreatography pancreatitis.

Background: Pancreatitis following endoscopic retrograde cholangiopancreatography (ERCP) can lead to significant morbidity and mortality. We aimed to develop an accurate post-ERCP pancreatitis risk prediction model using easily obtainable variables. Methods: Using prospective multi-center ERCP data, we performed logistic regression using stepwise selection on several patient-, procedure-, and endoscopist-related factors that were determined a priori. The final model was based on a combination of the Bayesian information criterion and Akaike's information criterion performance, balancing the inclusion of clinically relevant variables and model parsimony. All available data were used for model development, with subsequent internal validation performed on bootstrapped data using 10-fold cross-validation. Results: Data from 3021 ERCPs were used to inform models. There were 151 cases of post-ERCP pancreatitis (5.0% incidence). Variables included in the final model included female sex, pancreatic duct cannulation, native papilla status, pre-cut sphincterotomy, increasing cannulation time, presence of biliary stricture, patient age, and placement of a pancreatic duct stent. The final model was discriminating, with a receiver operating characteristic curve statistic of 0.79, and well-calibrated, with a predicted risk-to-observed risk ratio of 1.003. Conclusions: We successfully developed and internally validated a promising post-ERCP pancreatitis clinical prediction model using easily obtainable variables that are known at baseline or observed during the ERCP procedure. The model achieved an area under the curve of 0.79. External validation is planned as additional data becomes available.

Per-oral cholangioscopy in patients with primary sclerosing cholangitis: a 12-month follow-up study.

Background and study aims Patients with primary sclerosing cholangitis (PSC) have a 9% to 20% lifetime incidence of cholangiocarcinoma (CCA). Per-oral cholangioscopy (POCS) added to endoscopic retrograde cholangiography (ERC) could potentially improve detection of CCA occurrence. We prospectively assessed POCS identification of 12-month CCA incidence in PSC patients undergoing ERC. Patients and methods Consecutive patients with PSC, an indication for ERC, and no prior liver transplantation were enrolled. During the index procedure, POCS preceded planned therapeutic maneuvers. The primary endpoint was ability for POCS visualization with POCS-guided biopsy to identify CCA during 12-month follow-up. Secondary endpoints included ability of ERC/cytology to identify CCA, repeat ERC, liver transplantation, and serious adverse events (SAEs). Results Of 42 patients enrolled, 36 with successful cholangioscope advancement were analyzed. Patients had a mean age 43.5±15.6 years and 61% were male. Three patients diagnosed with CCA had POCS visualization impressions of benign/suspicious/suspicious, and respective POCS-guided biopsy findings of suspicious/positive/suspicious for malignancy at the index procedure. The three CCA cases had ERC visualization impressions of benign/benign/suspicious, and respective cytology findings of atypical/atypical/suspicious for malignancy. No additional patients were diagnosed with CCA during median 11.5-month follow-up. Twenty-three repeat ERCs (5 including POCS) were performed in 14 patients. Five patients had liver transplantation, one after CCA diagnosis and four after benign cytology at the index procedure. Three patients (7.1%) had post-ERC pancreatitis. No SAEs were POCS-related. Conclusions In PSC patients, POCS visualization/biopsy and ERC/cytology each identified three cases of CCA. Some patients had a repeat procedure and none experienced POCS-related SAEs.

The Bethesda ERCP Skills Assessment Tool (BESAT) can reliably differentiate endoscopists of different experience levels.

Background and study aims The Bethesda ERCP Skill Assessment Tool (BESAT) is a video-based assessment tool of technical endoscopic retrograde cholangiopancreatography (ERCP) skill with previously established validity evidence. We aimed to assess the discriminative validity of the BESAT in differentiating ERCP skill levels. Methods Twelve experienced ERCP practitioners from tertiary academic centers were asked to blindly rate 43 ERCP videos using the BESAT. ERCP videos consisted of native biliary cannulation and sphincterotomy and were recorded from 10 unique endoscopists of various ERCP experience (from advanced endoscopy fellow to > 10 years of ERCP experience). Inter-rater reliability, discriminative validity, and internal structure validity were subsequently assessed. Results The BESAT was found to reliably differentiate between endoscopists of varying levels of ERCP experience with experienced ERCPists scoring higher than novice ERCPists in 11 of 13 (85%) instrument items. Inter-rater reliability for BESAT items ranged from good to excellent (intraclass correlation range: 0.86 to 0.93). Internal structure validity was assessed with item-total correlations ranging from 0.53 to 0.83. Conclusions Study findings demonstrate that the BESAT, a video-based ERCP skill assessment tool, has high inter-rater reliability and has discriminative validity in differentiating novice from expert ERCP skill. Further investigations are needed to determine the role of video-based assessment in improving trainee learning curves and patient outcomes.

Indomethacin with or without prophylactic pancreatic stent placement to prevent pancreatitis after ERCP: a randomised non-inferiority trial.

BACKGROUND: The combination of rectally administered indomethacin and placement of a prophylactic pancreatic stent is recommended to prevent pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP) in high-risk patients. Preliminary evidence suggests that the use of indomethacin might eliminate or substantially reduce the need for stent placement, a technically complex, costly, and potentially harmful intervention. METHODS: In this randomised, non-inferiority trial conducted at 20 referral centres in the USA and Canada, patients (aged ≥18 years) at high risk for post-ERCP pancreatitis were randomly assigned (1:1) to receive rectal indomethacin alone or the combination of indomethacin plus a prophylactic pancreatic stent. Patients, treating clinicians, and outcomes assessors were masked to study group assignment. The primary outcome was post-ERCP pancreatitis. To declare non-inferiority, the upper bound of the two-sided 95% CI for the difference in post-ERCP pancreatitis (indomethacin alone minus indomethacin plus stent) would have to be less than 5% (non-inferiority margin) in both the intention-to-treat and per-protocol populations. This trial is registered with ClinicalTrials.gov (NCT02476279), and is complete. FINDINGS: Between Sept 17, 2015, and Jan 25, 2023, a total of 1950 patients were randomly assigned. Post-ERCP pancreatitis occurred in 145 (14·9%) of 975 patients in the indomethacin alone group and in 110 (11·3%) of 975 in the indomethacin plus stent group (risk difference 3·6%; 95% CI 0·6-6·6; p=0·18 for non-inferiority). A post-hoc intention-to-treat analysis of the risk difference between groups showed that indomethacin alone was inferior to the combination of indomethacin plus prophylactic stent (p=0·011). The relative benefit of stent placement was generally consistent across study subgroups but appeared more prominent among patients at highest risk for pancreatitis. Safety outcomes (serious adverse events, intensive care unit admission, and hospital length of stay) did not differ between groups. INTERPRETATION: For preventing post-ERCP pancreatitis in high-risk patients, a strategy of indomethacin alone was not as effective as a strategy of indomethacin plus prophylactic pancreatic stent placement. These results support prophylactic pancreatic stent placement in addition to rectal indomethacin administration in high-risk patients, in accordance with clinical practice guidelines. FUNDING: US National Institutes of Health.

Effectiveness and safety of thin vs. thick cold snare polypectomy of small colorectal polyps: Systematic review and meta-analysis.

Background and study aims Cold-snare polypectomy (CSP) is considered the standard of care for resection of colorectal polyps ≤10 mm. Data on the efficacy of CSP performed with thin-wire snares compared0 with thick-wire snares are conflicting. We performed a meta-analysis comparing complete resection (CR) and adverse event rates of CSP using thin-wire and thick-wire snares. Patients and methods Comparative studies of adult patients with ≧1 colorectal polyp(s) ≦10 mm who underwent CSP with thin-wire or thick-wire snares were included. We collected data on study, patient, polyp, and snare characteristics. The primary outcome was CR rate. Secondary outcomes were polyp retrieval rate, intraprocedural bleeding, delayed post-polypectomy bleeding, deep mural injury or perforation, patient discomfort, total sedation, and procedure time. We used random-effects models to calculate risk ratios for outcomes. We performed risk of bias assessments, rated the certainty of evidence, and assessed publication bias for all studies. Results We included four randomized controlled trials (RCTs) and two observational studies including 1316 patients with 1679 polyps (826 thin-wire CSPs and 853 thick-wire CSPs). There was no significant difference between thin-wire CSP (92.1%) and thick-wire CSP (87.7%) for RCTs (risk ratio [RR] 1.05, 95% confidence interval [CI] 0.94-1.16) or observational studies (78.1% versus 79.6%, RR 1.03, 95% CI 0.99-1.08). There were no significant differences in polyp retrieval rate or intraprocedural bleeding. There were no cases of delayed bleeding or perforation. Conclusions We found no differences in CR rates for CSP between thin-wire and thick-wire snares. CSP, regardless of snare type, is safe and effective for resection of small colorectal polyps.

Post-ERCP cholecystitis: Incidence, characteristics, and outcomes from a prospective multicenter biliary endoscopy registry.

BACKGROUND AND AIMS: The incidence, risk factors, and outcomes of post-ERCP cholecystitis are poorly described. We aimed to describe cases of post-ERCP cholecystitis from a prospective multicenter registry with protocolized 30-day follow-up. METHODS: Patient- and procedure-related data from 7 centers were obtained. The primary outcome was post-ERCP cholecystitis, defined according to a Delphi-based criteria and causal attribution system. Risk factors and outcomes were described for all cases. RESULTS: Seventeen cases of post-ERCP cholecystitis were identified among 4428 patients with gallbladders undergoing ERCP between 2018 and 2023 (incidence, 0.38%; 95% confidence interval, 0.20-0.57). In ERCPs with covered metal stenting, 7 of 467 resulted in cholecystitis (incidence, 1.50%; 95% confidence interval, 0.40-2.60). Patients had symptoms at a median of 5 days (interquartile range, 5) after ERCP. Management strategies included cholecystectomy, percutaneous cholecystostomy, and endoscopic stent removal/exchange. CONCLUSIONS: Estimates of post-ERCP cholecystitis incidence can inform discussions around procedural risk.

Aspirin exposure and its association with metal stent patency in malignant distal biliary obstruction: a large international multicenter propensity score-matched study.

BACKGROUND AND AIMS: Stent dysfunction is common after ERCP with self-expandable metal stent (SEMS) insertion for malignant distal biliary obstruction (MDBO). Chronic aspirin (acetylsalicylic acid; ASA) exposure has been previously shown to potentially decrease this risk. We aim to further ascertain the protective effect of ASA and to identify other predictors of stent dysfunction. METHODS: This multicenter retrospective cohort study was conducted at 9 sites in Canada and 1 in the United States. Patients with MDBO who underwent ERCP with SEMS placement between January 2014 and December 2019 were included and divided into 2 cohorts: ASA exposed (ASA-E) and ASA unexposed (ASA-U). Propensity-score matching (PSM) was performed to limit selection bias. Matched variables were age, sex, tumor stage, and type of metal stent. The primary outcome was the hazard rate of stent dysfunction. A multivariable Cox proportional hazards model was used to identify independent predictors of stent dysfunction. RESULTS: Of 1396 patients assessed, after PSM 496 patients were analyzed (248 ASA-E and 248 ASA-U). ERCP with SEMS placement was associated with a high clinical success of 82.2% in ASA-E and 81.2% in ASA-U cohorts (P = .80). One hundred eighty-four patients had stent dysfunction with a mean stent patency time of 229.9 ± 306.2 days and 245.4 ± 241.4 days in ASA-E and ASA-U groups, respectively (P = .52). On multivariable analysis, ASA exposure did not protect against stent dysfunction (hazard ratio [HR], 1.25; 95% confidence interval [CI], .96-1.63). An etiology of pancreatic cancer (HR, 1.36; 95% CI, 1.15-1.61) predicted stent dysfunction, whereas cancer therapy was protective (HR, .73; 95% CI, .55-.96). Chronic ASA use was not associated with an increased risk for adverse events including bleeding, post-ERCP pancreatitis, and perforation. CONCLUSIONS: In this large, multicenter study using PSM, chronic exposure to ASA did not protect against stent dysfunction in MDBO. Instead, the analysis revealed that the etiology of pancreatic cancer was an independent predictor of stent dysfunction and cancer therapy was protective.

Geometry of cold snare polypectomy and risk of incomplete resection.

BACKGROUND: Cold snare polypectomy (CSP) is safer than and equally efficacious as hot snare polypectomy (HSP) for the removal of small (<10mm) colorectal polyps. The maximum polyp size that can be effectively managed by piecemeal CSP (p-CSP) without an excessive burden of recurrence is unknown. METHODS: Resection error risks (RERs), defined as the estimated likelihood of incomplete removal of adenomatous tissue for a single snare resection pass, for CSP and HSP were calculated, based on an incomplete resection rate. Polyp area, snare size, estimated number of resections, and optimal resection defect area were modeled. Overall risk of incomplete resection (RIR) was defined as RIR=1 - (1 - p)n, where p is the RER and n the number of resections. RESULTS: A 40-mm polyp has a four times greater area than a 20-mm polyp (314.16mm2 vs. 1256.64mm2), and requires three times more resections (11 vs. 33, respectively, assuming 8-mm piecemeal resection pieces for p-CSP). RIRs for a 40-mm polyp by HSP and p-CSP were 15.1%-23% and 40.74%-60.60% respectively. CONCLUSION: RER is more important with p-CSP than with HSP. The number of resections, n, and consequently RIR increases with increasing polyp size. Given the overwhelming safety of CSP, specific techniques to minimize the RER should be studied and developed.

EUS-guided gastroenterostomy using a novel through-the-scope exchangeable dual-balloon enteroclysis catheter: a potentially secure and scalable approach.

Video 1Clinical case of dual-balloon through-the-scope exchangeable enteroclysis catheter-assisted EUS-guided gastroenterostomy.

Prolonged Gastrointestinal Manifestations After Recovery From COVID-19.

BACKGROUND & AIMS: Acute enteric infections are well known to result in long-term gastrointestinal (GI) disorders. Although COVID-19 is principally a respiratory illness, it demonstrates significant GI tropism, possibly predisposing to prolonged gut manifestations. We aimed to examine the long-term GI impact of hospitalization with COVID-19. METHODS: Nested within a large-scale observational cohort study of patients hospitalized with COVID-19 across North America, we performed a follow-up survey of 530 survivors 12-18 months later to assess for persistent GI symptoms and their severity, and for the development of disorders of gut-brain interaction (DGBIs). Eligible patients were identified at the study site level and surveyed electronically. The survey instrument included the Rome IV Diagnostic Questionnaire for DGBI, a rating scale of 24 COVID-related symptoms, the Gastrointestinal Symptoms Rating Scale, and the Impact of Events-Revised trauma symptom questionnaire (a measure of posttraumatic stress associated with the illness experience). A regression analysis was performed to explore the factors associated with GI symptom severity at follow-up. RESULTS: Of the 530 invited patients, 116 responded (52.6% females; mean age, 55.2 years), and 73 of those (60.3%) met criteria for 1 or more Rome IV DGBI at follow-up, higher than the prevalence in the US general population (P < .0001). Among patients who experienced COVID-related GI symptoms during the index hospitalization (abdominal pain, nausea, vomiting, or diarrhea), 42.1% retained at least 1 of these symptoms at follow-up; in comparison, 89.8% of respondents retained any (GI or non-GI) COVID-related symptom. The number of moderate or severe GI symptoms experienced during the initial COVID-19 illness by self-report correlated with the development of DGBI and severity of GI symptoms at follow-up. Posttraumatic stress disorder (Impact of Events-Revised score ≥33) related to the COVID-19 illness experience was identified in 41.4% of respondents and those individuals had higher DGBI prevalence and GI symptom severity. Regression analysis revealed that higher psychological trauma score (Impact of Events-Revised) was the strongest predictor of GI symptom severity at follow-up. CONCLUSIONS: In this follow-up survey of patients 12-18 months after hospitalization with COVID-19, there was a high prevalence of DGBIs and persistent GI symptoms. Prolonged GI manifestations were associated with the severity of GI symptoms during hospitalization and with the degree of psychological trauma related to the illness experience.

ERCP-related adverse events: incidence, mechanisms, risk factors, prevention, and management.

INTRODUCTION: Endoscopic retrograde cholangiopancreatography (ERCP) is a commonly performed procedure for pancreaticobiliary disease. While ERCP is highly effective, it is also associated with the highest adverse event (AE) rates of all commonly performed endoscopic procedures. Thus, it is critical that endoscopists and caregivers of patients undergoing ERCP have clear understandings of ERCP-related AEs. AREAS COVERED: This narrative review provides a comprehensive overview of the available evidence on ERCP-related AEs. For the purposes of this review, we subdivide the presentation of each ERCP-related AE according to the following clinically relevant domains: definitions and incidence, proposed mechanisms, risk factors, prevention, and recognition and management. The evidence informing this review was derived in part from a search of the electronic databases PubMed, Embase, and Cochrane, performed on 1 May 20231 May 2023. EXPERT OPINION: Knowledge of ERCP-related AEs is critical not only given potential improvements in peri-procedural quality and related care that can ensue but also given the importance of reviewing these considerations with patients during informed consent. The ERCP community and researchers should aim to apply standardized definitions of AEs. Evidence-based knowledge of ERCP risk factors should inform patient care decisions during training and beyond.

Endoscopic Submucosal Dissection Versus Surgery or Endoscopic Mucosal Resection for Metachronous Early Gastric Cancer: a Meta-analysis.

BACKGROUND: Resection options for early gastric cancer (EGC) include endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR), and surgery. In patients with metachronous EGC following previous resection, the optimal resection technique is not well elucidated. We conducted a systematic review and meta-analysis of studies comparing ESD to EMR, or ESD to surgery, in patients with metachronous EGC. METHODS: We conducted an electronic search of studies reporting on outcomes and AEs following ESD versus either EMR or surgery for patients with metachronous EGC. Pooled odds ratios (OR) of included studies were obtained using DerSimonian and Laird random effects models. Funnel plots were produced and visually inspected for evidence of publication bias. The quality of the evidence was assessed using GRADE. RESULTS: A total of 9367 abstracts were screened and 10 observational studies were included. The odds of complete resection were higher amongst patients undergoing ESD compared to EMR (OR 5.88, 95% confidence intervals, CI, 1.79-19.35), whereas the odds of complete resection were no different between ESD and surgery (OR 0.57, 95% CI 0.04-8.24). There were no differences in the odds of local recurrence with ESD versus surgery (OR 5.01, 95% CI 0.86-29.13). Post-procedural bleeding did not differ significantly between ESD and EMR (OR 0.70, 95% CI 0.16-3.00). There was no evidence of publication bias. DISCUSSION: For metachronous EGC, ESD or surgery is preferred over EMR depending on local expertise and patient preferences, largely due to a higher risk of incomplete resection with EMR. REVIEW REGISTRATION: PROSPERO CRD42021270445.

Endoscopic Ultrasound-Guided Biliary Drainage of First Intent With a Lumen-Apposing Metal Stent vs Endoscopic Retrograde Cholangiopancreatography in Malignant Distal Biliary Obstruction: A Multicenter Randomized Controlled Study (ELEMENT Trial).

BACKGROUND & AIMS: Endoscopic ultrasound-guided choledochoduodenostomy with a lumen-apposing metal stent (EUS-CDS) is a promising modality for management of malignant distal biliary obstruction (MDBO) with potential for better stent patency. We compared its outcomes with endoscopic retrograde cholangiopancreatography with metal stenting (ERCP-M). METHODS: In this multicenter randomized controlled trial, we recruited patients with MDBO secondary to borderline resectable, locally advanced, or unresectable peri-ampullary cancers across 10 Canadian institutions and 1 French institution. This was a superiority trial with a noninferiority assessment of technical success. Patients were randomized to EUS-CDS or ERCP-M. The primary end point was the rate of stent dysfunction at 1 year, considering competing risks of death, clinical failure, and surgical resection. Analyses were performed according to intention-to-treat principles. RESULTS: From February 2019 to February 2022, 144 patients were recruited; 73 were randomized to EUS-CDS and 71 were randomized to ERCP-M. The mean (SD) procedure time was 14.0 (11.4) minutes for EUS-CDS and 23.1 (15.6) minutes for ERCP-M (P < .01); 40% of the former was performed without fluoroscopy. Technical success was achieved in 90.4% (95% CI, 81.5% to 95.3%) of EUS-CDS and 83.1% (95% CI, 72.7% to 90.1%) of ERCP-M with a risk difference of 7.3% (95% CI, -4.0% to 18.8%) indicating noninferiority. Stent dysfunction occurred in 9.6% vs 9.9% of EUS-CDS and ERCP-M cases, respectively (P = .96). No differences in adverse events, pancreaticoduodenectomy and oncologic outcomes, or quality of life were noted. CONCLUSIONS: Although not superior in stent function, EUS-CDS is an efficient and safe alternative to ERCP-M in patients with MDBO. These findings provide evidence for greater adoption of EUS-CDS in clinical practice as a complementary and exchangeable first-line modality to ERCP in patients with MDBO. CLINICALTRIALS: gov, Number: NCT03870386.