Quality assurance in the prospective multi-institutional trial on definitive radiotherapy using high-dose-rate intracavitary brachytherapy for uterine cervical cancer: the individual case review

Purpose:To assess the protocol compliance of radiotherapy in the multi-institutional prospective study (JAROG0401) which investigates the efficacy and toxicity of definitive radiotherapy using high-dose rate intracavitary brachytherapy (HDR-ICBT) for patients with early stage uterine cervical cancer. \nMaterials and Methods:Individual case review (ICR) on radiotherapy of all 60 patients entered into the study was performed. Patient data including pretreatment MRI (T2WI), data of external beam radiotherapy (EBRT) (treatment chart, simulation films/ DRR, portal films/ EPID, and dose distributions), and data of HDR-ICBT (treatment chart, AP/ lateral orthogonal films, and isodose distributions for all insertions) were collected by security mails. All radiological images and dose distributions were digitally processed, mounted on Microsoft PowerPoint, in CD-ROM. Other data such as treatment charts were submitted as hard copies. Radiotherapy parameters reviewed were clearly stated in the study protocol. Protocol compliance of radiotherapy was evaluated on 16 items according to the criteria developed. The data were reviewed and evaluated in the quality assurance (QA) committee of the JAROG consisting of participating radiation oncologists. The QA committee was held and ICR was performed for three times during the patient accrual period. ICR results of each QA committee were feedback immediately to the participating institutions. \nResults38 of the 60 patients (63%) were evaluated "acceptable" for all 16 items according to the criteria. The items provided by quantitative values, such as prescribed doses, some time intervals and overall treatment were well followed. Number of cases evaluated "deviation" decreased by each QA committee; 6/15 in the 1st committee, 7/20 in the 2nd, and 6/25 in the 3rd. 10 patients (17%) were evaluated "deviation" on the method of point A determination.\nConclusionPresent ICR demonstrated compliance to protocol of radiotherapy was generally good. Decreasing "deviation" through each QA committee suggested the QA program could improve protocol compliance of radiotherapy. A dummy run or benchmark case evaluation might work effectively for some QA, such as point A determination, in the future multi-institutional study involving HDR-ICBT.ESTRO2

A novel approach to address external validity issues in fault prediction using bandit algorithms

Various software fault prediction models have been proposed in the past twenty years. Many studies have compared and evaluated existing prediction approaches in order to identify the most effective ones. However, in most cases, such models and techniques provide varying results, and their outcomes do not result in best possible performance across different datasets. This is mainly due to the diverse nature of software development projects, and therefore, there is a risk that the selected models lead to inconsistent results across multiple datasets. In this work, we propose the use of bandit algorithms in cases where the accuracy of the models are inconsistent across multiple datasets. In the experiment discussed in this work, we used four conventional prediction models, tested on three different dataset, and then selected the best possible model dynamically by applying bandit algorithms. We then compared our results with those obtained using majority voting. As a result, Epsilon-greedy with ϵ = 0.3 showed the best or second-best prediction performance compared with using only one prediction model and majority voting. Our results showed that bandit algorithms can provide promising outcomes when used in fault prediction.</p