Multicenter external validation of the liverpool uveal melanoma prognosticator online: An OOG collaborative study

Uveal melanoma (UM) is fatal in ~50% of patients as a result of disseminated disease. This study aims to externally validate the Liverpool Uveal Melanoma Prognosticator Online V3 (LUMPO3) to determine its reliability in predicting survival after treatment for choroidal melanoma when utilizing external data from other ocular oncology centers. Anonymized data of 1836 UM patients from seven international ocular oncology centers were analyzed with LUMPO3 to predict the 10-year survival for each patient in each external dataset. The analysts were masked to the patient outcomes. Model predictions were sent to an independent statistician to evaluate LUMPO3’s performance using discrimination and calibration methods. LUMPO3’s ability to discriminate between UM patients who died of metastatic UM and those who were still alive was fair-to-good, with C-statistics ranging from 0.64 to 0.85 at year 1. The pooled estimate for all external centers was 0.72 (95% confidence interval: 0.68 to 0.75). Agreement between observed and predicted survival probabilities was generally good given differences in case mix and survival rates between different centers. Despite the differences between the international cohorts of patients with primary UM, LUMPO3 is a valuable tool for predicting all-cause mortality in this disease when using data from external centers

Competency Assessment of Final-Year Dental Students in Tunisia

Introduction. The educational program assessment has always been the main objective of quality improvement in all curricula. The aim of this study was to describe the levels of competency of final-year students of the Faculty of Dental Medicine of Monastir in Tunisia in the major skills needed for a new dentist. Methods. In this cross-sectional descriptive study, 154 students filled out a questionnaire including 53 competencies, rated on a four-point Likert scale, broadly based on the competencies described in the profile and competences for the graduating dentist in Europe. Results. The response rate was 67% (145/230). For twenty items in the questionnaire, over 75% of the students reported being competent. The five items with the highest percentages were “undertaking supragingival and subgingival scaling-Item 22” (97.2%), “evaluating the periodontium, establishing a diagnosis and formulating a treatment plan-Item 2” (96.6%), “identify the location and degree of activity of dental caries-Item 24 (95.9%), “taking and interpreting dental radiographs-Item 12” (94.4%), “restoring damaged teeth-Item 25” (93.8%), and “managing primary oral health care-Item 16” (93.8%). For eighteen skills, more than 75% of students self-rated being not competent, demonstrating a need of more thorough training, notably in periodontal surgery and implantology, among these, five skills were found that demand in-depth acquisition according to the students. Conclusion. The general state of competency of the last-year dental students was described as fairly satisfactory based on the students’ self-reported responses. However, theoretical and practical backgrounds related to some subjects in the school need to be improved

Design, Construction and Performance Evaluation of a Manually Operated Meat Mincing Machine

In this study, a manually operated meat mincing machine was designed, constructed and its performance evaluated. The machine consists of; a single start worm auger called the shaft, a four-blade crosshead knife, a perforated plate, handle, mincing cover and a mincing head which comprised a hopper and an anchor bracket. All components of the machine were fabricated from locally available materials (stainless and mild steel) and based on the determined design parameters. The auger, mincing head, the crosshead knife and perforated plate were constructed from stainless steel material. Mild steel was used for the construction of the anchor bracket, mincing head cover and handle of the machine. These components were fabricated using the process of measurement, marking, cutting and joining. Vernier caliper and steel rule were used for measurement, scriber used for marking, center lathe machine, drilling machine, hark saw, hand snip and hand files were used for cutting. While arc welding and bolting were used the joining process. The auger had a shaft diameter of 0.025 m, worm diameter of 0.05 m and a total length of 0.22 m. The mincing head had an internal diameter of 0.052 m and external diameter of 0.06 m. The result shows that the machine can mince  fresh meat in  seconds,  of perboiled meat in  seconds and  of overcooked meat in  seconds. The critical load of the auger which is the major component of the machine is  with a maximum stress of  The efficiency of the machine was 50% at a velocity ratio of 0.88 and mechanical advantage of 1.8 with a total production cost of seven thousand three hundred and ninety two naira (₦7,392). The machine will serve as a means of providing minced meat to children, elderly and the sick especially in rural areas that have no access to electricity

Assessing flexible models and rule extraction from censored survival data

The evaluation of generic non-linear models for censored data needs to address the two complementary requirements in the software development life-cycle, of validation and verification. The former involves making a rigorous assessment of predictive accuracy in prognostic modelling and the latter is interpreted in this paper as comprising two different stages, namely model selection and rule-based interpretation of the composition of prognostic risk groups. With reference to prognostic performance is survival modelling the well-known ROC framework has recently been extended to a threshold independent, time-dependent performance index to quantify the predictive accuracy of censored data models, termed the Ctd index, which is briefly described. The rule-based framework for direct validation of risk group allocation against expert domain knowledge, uses low-order Boolean rules to approximate the response surfaces generated by analytical inference models. In the case of censored data, this approach serves to characterise the allocation of patients into risk groups generated by a risk staging index. Furthermore, the low-order rules define low-dimensional sub-spaces where individual data points can be directly visualised in relation to the decision boundaries for their risk group. Taken together, the quantitative performance index, Boolean explanatory rules and direct visualisation of the data, define a consistent and transparent validation framework based on triangulation of information. This information can be included in decision support systems