15 research outputs found

    A Bayesian test for excess zeros in a zero-inflated power series distribution

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    Power series distributions form a useful subclass of one-parameter discrete exponential families suitable for modeling count data. A zero-inflated power series distribution is a mixture of a power series distribution and a degenerate distribution at zero, with a mixing probability pp for the degenerate distribution. This distribution is useful for modeling count data that may have extra zeros. One question is whether the mixture model can be reduced to the power series portion, corresponding to p=0p=0, or whether there are so many zeros in the data that zero inflation relative to the pure power series distribution must be included in the model i.e., p≥0p\geq0. The problem is difficult partially because p=0p=0 is a boundary point. Here, we present a Bayesian test for this problem based on recognizing that the parameter space can be expanded to allow pp to be negative. Negative values of pp are inconsistent with the interpretation of pp as a mixing probability, however, they index distributions that are physically and probabilistically meaningful. We compare our Bayesian solution to two standard frequentist testing procedures and find that using a posterior probability as a test statistic has slightly higher power on the most important ranges of the sample size nn and parameter values than the score test and likelihood ratio test in simulations. Our method also performs well on three real data sets.Comment: Published in at http://dx.doi.org/10.1214/193940307000000068 the IMS Collections (http://www.imstat.org/publications/imscollections.htm) by the Institute of Mathematical Statistics (http://www.imstat.org

    Amivantamab compared with real-world therapies in patients with advanced non-small cell lung cancer harboring EGFR exon 20 insertion mutations who progressed after platinum-based chemotherapy

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    BACKGROUND: In the single-arm CHRYSALIS study, amivantamab showed durable responses and manageable safety in patients with advanced non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) exon 20 insertion mutations (ex20ins) who progressed on prior platinum-based chemotherapy. External controls can provide context for interpreting amivantamab efficacy. METHODS: External controls were selected from three US-based databases (ConcertAI, COTA, and Flatiron). Key inclusion criteria were diagnosis of EGFR ex20ins advanced NSCLC, prior platinum-based chemotherapy, and performance status score ≤ 1. Duplicate external controls were identified using a tokenization procedure and removed, and adjustment for differences in baseline characteristics between amivantamab-treated and external control cohorts was achieved using propensity score weighting. RESULTS: Amivantamab-treated and pooled external control cohorts included 81 and 125 patients, respectively. Baseline characteristics were generally similar across cohorts, except more amivantamab-treated patients were Asian (56% vs 13%). Most common therapies received by external controls were non-platinum-based chemotherapy (25.1%), immuno-oncology therapies (24.2%), EGFR tyrosine kinase inhibitors (16.3%), and platinum-based chemotherapy (16.3%). Overall response rate was 40% among amivantamab-treated patients and 16% among external controls. Amivantamab-treated patients had longer progression-free survival (median 8.3 vs 2.9 months; hazard ratio [HR; 95% CI]: 0.47 [0.34-0.65]), time to next therapy (median 14.8 vs 4.8 months; HR [95% CI]: 0.40 [0.28-0.57]), and overall survival (median 22.8 vs 12.8 months; HR [95% CI]: 0.49 [0.31-0.77]) than external controls. Results were consistent in sensitivity analyses comparing each external control dataset against the amivantamab-treated group separately. CONCLUSION: Among post-platinum patients with EGFR ex20ins advanced NSCLC, those treated with amivantamab had improved outcomes, including 10-month longer overall survival, versus external controls

    Association between ultrasound-detected synovitis and knee pain: a population-based case-control study with both cross-sectional and follow-up data

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    Background: Recently an important role for synovial pathology in the initiation and progression of knee osteoarthritis (OA) has been emphasised. This study aimed to examine whether ultrasonographydetected synovial changes (USSCs) associate with knee pain (KP) in a community population. Methods: A case-control study was conducted to compare people with early KP (n=298), established KP (n=100) or no KP (n=94) at baseline. Multinomial logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI) between groups adjusted for radiographic osteoarthritis (ROA) severity and other confounding factors. After one year 255 participants with early and established KP completed the followup questionnaire for changes in KP. Logistic regression with adjustment was used to determine predictors of KP worsening. Results: At baseline, effusion was associated with early (OR 2.64, 95%CI 1.57 to 4.45) and established KP (OR 5.07, 95%CI 2.74 to 9.38). Synovial hypertrophy was also associated with early (OR 5.43, 95%CI 2.12 to 13.92) and established KP (OR 13.27, 95%CI 4.97 to 35.43). The association with effusion diminished when adjusted for ROA. Power Doppler signal was uncommon (early KP 3%, established KP 2%, controls 0%). Baseline effusion predicted worsening of knee pain at one year (OR 1.95, 95% CI 1.05 to 3.64). However, after adjusting for ROA, the prediction was insignificant (aORs 0.95, 95%CI 0.44 to 2.02). Conclusion: US effusion and synovial hypertrophy are associated with KP, but only effusion predicts KP worsening. However, the association/prediction are not independent from ROA. Power Doppler signal is uncommon in people with KP. Further study is needed to understand whether synovitis is directly involved in different types of KP

    NLT fibre broadband: Unlocking the RAB model in telecom

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    SMU Faculty/Staff can download the case and teaching note with your SMU login ID and Password via the following links: · The Case (SMU-21-0040) · Teaching Note (SMU-21-0040TN) For purchase of the case and supplementary materials via The CMP Shop, please access the following link: The Case (SMU-21-0040) For purchase of the case and supplementary materials via The Case Centre, please access the following links: · The Case (SMU-21-0040) · Teaching Note (SMU-21-0040TN) For purchase of the case and supplementary materials via Harvard Business Publishing, please access the following links: · The Case (SMU-21-0040) · Teaching Note (SMU-21-0040TN) </ul

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    Not AvailableCapacity building and skill development of officials who work with fishermen at zrassroors level is of utmost importance for efficient inland fishery management. The present study aims at finding out the impact of training of trainers (To'T) conducted by ICAR-Central Inland Fisheries Research Institute in terms of knowledge, attitude and skill (KAS) development. A total of 105 trainees of five training programmes in several areas of inland fisheries management were interviewed using structured interview schedule and telephonic interview. Knowledge test and attitude scale were developed for the purpose of the study. Trainees mostly fell in the medium category (51.19%) of knowledge before training and in the high category (45.24%) after the training prgrammes. Overall level of attitude was found to be skewed towards neutral before the training programmes while after the training programmes it was found to be skewed towards favourable. Statistically significant gain in knowledge was noticed for all the training programmes, while in case of attitude significant change was found in case of two training programmes. Skill acquirement was measured based on trainees' perception. Most of the trainees stated that they had acquired skill either "to satisfactory extent" or "to some extent". The study also found significantly positive correlations between the three domains under investigation. The results of the study would help to design efficient training programmes in future and would pave the way for conducting further research in training impact assessment on job performance of trainees.Not Availabl

    Relative efficacy of topical non-steroidal anti-inflammatory drugs and topical capsaicin in osteoarthritis: Protocol for an individual patient data meta-analysis

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    Background: Pain is the most troubling issue to patients with osteoarthritis (OA), yet current pharmacological treatments offer only small-to-moderate pain reduction. Current guidelines therefore emphasise the need to identify predictors of treatment response. In line with these recommendations, an individual patient data (IPD) meta-analysis will be conducted. The study aims to investigate the relative treatment effects of topical non-steroidal anti-inflammatory drugs (NSAIDs) and topical capsaicin in OA and to identify patient-level predictors of treatment response. Methods: IPD will be collected from randomised controlled trials (RCTs) of topical NSAIDs and capsaicin in OA. Multilevel regression modelling will be conducted to determine predictors for the specific and the overall treatment effect. Discussion: Through the identification of treatment responders, this IPD meta-analysis may improve the current understanding of the pain mechanisms in OA and guide clinical decision-making. Identifying and prescribing the treatment most likely to be beneficial for an individual with OA will improve the efficiency of patient management

    Identifying placebo responders and predictors of response in osteoarthritis: a protocol for individual patient data meta-analysis

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    Background: The management of osteoarthritis (OA) is unsatisfactory, as most treatments are not clinically effective over placebo and most drugs have considerable side effects. On average, 75 % of the analgesic effect from OA treatments in clinical trials can be attributed to a placebo response, and this response varies greatly from patient to patient. This individual patient data (IPD) meta-analysis aims to identify placebo responders and the potential determinants of the placebo response in OA. Methods: This study is undertaken in conjunction with the OA Trial Bank, an ongoing international consortium aiming to collect IPD from randomised controlled trials (RCTs) for all treatments of OA. RCTs for each treatment of OA have been systematically searched for, and authors of the relevant trials have been contacted to request the IPD. We will use the IPD of placebo-controlled RCTs held by the OA Trial Bank for this project. The IPD in placebo groups will be used to investigate the placebo response according to the minimum clinically important difference (MCID) threshold (e.g. 20 % pain reduction). Responders to placebo will be compared with non-responders to identify predictors of response. The quality of the trials will be assessed and potential determinants will be examined using multilevel logistic regression analyses. Discussion: This study explores the varying magnitude of the placebo response and the proportion of participants that experience a clinically important placebo effect in OA RCTs. Potential determinants of the placebo response will also be investigated. These determinants may be useful for future studies as it may allow participants to be stratified into groups based on their likely response to placebo. The results of this study may also be useful for pharmaceutical companies, who could improve the design of their studies in order to separate the specific treatment from the non-specific contextual (i.e. placebo) effects
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