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Decisions on how to calibrate an item bank might have major implications in the subsequent performance of the adaptive algorithms. One of these decisions is model selection, which can become problematic in the context of cognitive diagnosis computerized adaptive testing, given the wide range of models available. This article aims to determine whether model selection indices can be used to improve the performance of adaptive tests. Three factors were considered in a simulation study, that is, calibration sample size, Q-matrix complexity, and item bank length. Results based on the true item parameters, and general and single reduced model estimates were compared to those of the combination of appropriate models. The results indicate that fitting a single reduced model or a general model will not generally provide optimal results. Results based on the combination of models selected by the fit index were always closer to those obtained with the true item parameters. The implications for practical settings include an improvement in terms of classification accuracy and, consequently, testing time, and a more balanced use of the item bank. An R package was developed, named cdcatR, to facilitate adaptive applications in this context.Despite the increasing popularity, cognitive diagnosis models have been criticized for limited utility for small samples. In this study, the authors proposed to use Bayes modal (BM) estimation and monotonic constraints to stabilize item parameter estimation and facilitate person classification in small samples based on the generalized deterministic input noisy "and" gate (G-DINA) model. Both simulation study and real data analysis were used to assess the utility of the BM estimation and monotonic constraints. Results showed that in small samples, (a) the G-DINA model with BM estimation is more likely to converge successfully, (b) when prior distributions are specified reasonably, and monotonicity is not violated, the BM estimation with monotonicity tends to produce more stable item parameter estimates and more accurate person classification, and (c) the G-DINA model using the BM estimation with monotonicity is less likely to overfit the data and shows higher predictive power.Ipsative tests with multidimensional forced-choice (MFC) items have been widely used to assess career interest, values, and personality to prevent response biases. SEW 2871 Recently, there has been a surge of interest in developing item response theory models for MFC items. In reality, a statement in an MFC item may have different utilities for different groups, which is referred to as differential statement functioning (DSF). However, few studies have been investigated methods for detecting DSF owing to the challenges related to the features of ipsative tests. In this study, three methods were adapted for DSF assessment in MFC items equal-mean-utility (EMU), all-other-statement (AOS), and constant-statement (CS). Simulation studies were conducted to evaluate the recovery of parameters and the performance of the proposed methods. Results showed that statement parameters and DSF parameters were well recovered for all the three methods when the test did not contain any DSF statement. When the test contained one or more DSF statements, only the CS method yielded accurate estimates. With respect to DSF assessment, both the EMU method using the bootstrap standard error and the AOS method performed appropriately so long as the test did not contain any DSF statement. The CS method performed well in cases where one or more DSF-free statements were chosen as an anchor. The longer the anchor statements, the higher the power of DSF detection.Slipped capital femoral epiphysiolysis (SCFE) may result in femoroacetabular impingement (FAI) of the hip in up to one third of the cases. Residual deformity of the cam-type, or "pistol-grip", is associated with chondrolabral injury, resulting in pain, functional disability, and early osteoarthritis. The arthroscopic treatment with osteochondroplasty proved to be beneficial in a selected case of FAI secondary to SCFE.Schwannomas are benign slow-growing tumors that constitute 8% of all soft-tissue tumors. The clinical signs and symptoms are often misinterpreted because of the low incidence, and these tumors are often misdiagnosed. A 39-year-old male patient presented with non-traumatic solitary swelling in the posteromedial aspect of the right ankle that gradually increased in size and was associated with pain. Clinically, the swelling was firm, non-fluctuant, and was not associated with sensorimotor impairment. Surgical excision of the swelling was performed without damaging the surrounding vessels and nerves. The histopathological examination of the excised tumor revealed a schwannoma.Arachnoid cysts are rare; they can occur at all levels of the dural sac, and can have a congenital, traumatic, iatrogenic or inflammatory origin. In the present article, we report a patient presenting a compressive thoracic myelopathy due to an unusual intradural arachnoid cyst with posttraumatic manifestation and its resolution, in addition to a literature review on the subject. These cysts mainly occur at the thoracic spine, followed by the lumbar, lumbosacral and thoracolumbar spines. Traumatic cysts are caused by an injury to the inner dural layer. These lesions produce neurological deficits through a mass effect on the spinal cord. Concomitant compressive myelopathy is even rarer. In case of myelopathy, cyst resection or drainage is the treatment of choice, and it must be performed immediately. Although rare, arachnoid cysts can be a complication of spine fractures; as such, orthopedists and neurosurgeons, who commonly see these injuries, must be prepared for this unusual situation.The method presented here consists of a minimally invasive surgical technique for osteosynthesis of transtrochanteric fractures with Dynamic Hip Screw (DHS) 135°. It is indicated in the treatment of 31-A1 and 31-A2 fractures (Arbeitsgemeinschaft für Osteosynthesefragen Classification - AO) that meet the prerequisites required for using DHS. The surgery is performed, preferably, before 48 hours after the fracture. With the use of the same instruments as the traditional surgical technique and the aid of the C-arm, a closed reduction of the fracture and implantation of the DHS is performed by a 2-cm surgical incision, through dissection of the underlying tissues, with minimal bleeding and damage to the soft parts. In the immediate postoperative period, the patient is encouraged to orthostatism and walk with full load, which anticipates hospital discharge and favors early functional rehabilitation. Outpatient return is scheduled at 2, 6, 12 and 24 weeks postoperatively, with radiographic evaluation to assess fracture healing.
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