PURPOSE: Computerized adaptive testing (CAT) has been adopted in licensing examinations because it improves the efficiency and accuracy of the tests, as shown in many studies. This simulation study investigated CAT scoring and item selection methods for the Korean Medical Licensing Examination (KMLE). METHODS: This study used a post-hoc (real data) simulation design. The item bank used in this study included all items from the January 2017 KMLE. All CAT algorithms for this study were implemented using the ‘catR’ package in the R program. RESULTS: In terms of accuracy, the Rasch and 2-parametric logistic (PL) models performed better than the 3PL model. The ‘modal a posteriori’ and ‘expected a posterior’ methods provided more accurate estimates than maximum likelihood estimation or weighted likelihood estimation. Furthermore, maximum posterior weighted information and minimum expected posterior variance performed better than other item selection methods. In terms of efficiency, the Rasch model is recommended to reduce test length. CONCLUSION Before implementing live CAT, a simulation study should be performed under varied test conditions. Based on a simulation study, and based on the results, specific scoring and item selection methods should be predetermined.

PURPOSE: Computerized adaptive testing (CAT) has been adopted in licensing examinations because it improves the efficiency and accuracy of the tests, as shown in many studies. This simulation study investigated CAT scoring and item selection methods for the Korean Medical Licensing Examination (KMLE). METHODS: This study used a post-hoc (real data) simulation design. The item bank used in this study included all items from the January 2017 KMLE. All CAT algorithms for this study were implemented using the ‘catR’ package in the R program. RESULTS: In terms of accuracy, the Rasch and 2-parametric logistic (PL) models performed better than the 3PL model. The ‘modal a posteriori’ and ‘expected a posterior’ methods provided more accurate estimates than maximum likelihood estimation or weighted likelihood estimation. Furthermore, maximum posterior weighted information and minimum expected posterior variance performed better than other item selection methods. In terms of efficiency, the Rasch model is recommended to reduce test length. CONCLUSION: Before implementing live CAT, a simulation study should be performed under varied test conditions. Based on a simulation study, and based on the results, specific scoring and item selection methods should be predetermined.
Animals ; Cats ; Korea ; Licensure ; Logistic Models ; Research Design

This study introduces LIVECAT, a web-based computerized adaptive testing platform. This platform provides many functions, including writing item content, managing an item bank, creating and administering a test, reporting test results, and providing information about a test and examinees. The LIVECAT provides examination administrators with an easy and flexible environment for composing and managing examinations. It is available at http://www.thecatkorea.com/. Several tools were used to program LIVECAT, as follows: operating system, Amazon Linux; web server, nginx 1.18; WAS, Apache Tomcat 8.5; database, Amazon RDMS—Maria DB; and languages, JAVA8, HTML5/CSS, Javascript, and jQuery. The LIVECAT platform can be used to implement several item response theory (IRT) models such as the Rasch and 1-, 2-, 3-parameter logistic models. The administrator can choose a specific model of test construction in LIVECAT. Multimedia data such as images, audio files, and movies can be uploaded to items in LIVECAT. Two scoring methods (maximum likelihood estimation and expected a posteriori) are available in LIVECAT and the maximum Fisher information item selection method is applied to every IRT model in LIVECAT. The LIVECAT platform showed equal or better performance compared with a conventional test platform. The LIVECAT platform enables users without psychometric expertise to easily implement and perform computerized adaptive testing at their institutions. The most recent LIVECAT version only provides a dichotomous item response model and the basic components of CAT. Shortly, LIVECAT will include advanced functions, such as polytomous item response models, weighted likelihood estimation method, and content balancing method.

Spinal extradural arachnoid cysts (SEACs) are rare and usually asymptomatic, and they usually do not require surgical treatment. If symptoms manifest, however, surgical treatment is required. A 25-year-old male patient complained of impotence upon admission. Magnetic resonance images (MRIs) of his lumbar spine showed a SEAC located longitudinally from the T11 to L3, which was accompanied by thecal sac compression. Verifying the location of the dural defect is crucial for minimizing surgical treatments. Cystography, myelography, and lumbar spine MRI were conducted to locate the leak in real-time; however, it was not found.Hence, the location of the cerebrospinal fluid leak was estimated based on cystography, computed tomography, myelography, and MRI findings. We suggest that the region with the earliest contrast-filling, as well as the middle and widest area of the cyst, may correspond to the location of the dural defect.

OBJECTIVE: The laboratory biomarkers used to diagnose spinal infection include white blood cell (WBC) counts, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Recently, procalcitonin (PCT) has been used as a biomarker to distinguish between bacterial infection and non-bacterial infection. We aimed to compare the changes of conventional biomarker and PCT in patients with spinal infection before and after antibiotic treatment. METHODS: ESR, CRP, WBC counts, and PCT were measured in 29 patients diagnosed with pyogenic spinal infection at our hospital between May 2016 and December 2018 prior to antibiotic administration. After antibiotic administration, the values were followed up for 4 weeks at 1-week intervals. RESULTS: A total of 29 patients were enrolled, with a mean age of 67.8 years, consisting of 16 men and 13 women. Twenty-five patients had lumbar infections, and 2 each had cervical and thoracic infections. The mean ESR, CRP, PCT, and WBCs decreased at week 4 of antibiotic treatment compared to their baseline values. CRP and WBCs were significantly decreased after 4 weeks of treatment compared to before treatment. The mean ESR and PCT was not statistically significant compared to pretreatment and after antibiotic treatment (p-value>0.05). CONCLUSION: Among several biomarker, CRP and WBCs are biomarkers that can aid early evaluation of the effects of antibiotic treatment in pyogenic spondylitis. Although PCT did not have statistical significance, it can be used as a biomarker that reflects the effect of antibiotic and severity of infection.
Bacterial Infections ; Biomarkers ; C-Reactive Protein ; Calcitonin ; Erythrocyte Count ; Female ; Humans ; Leukocytes ; Male ; Spondylitis

Thoracic outlet syndrome is a relatively well known disease. Other than trauma, this disease is mostly caused by anatomical structures that cause vascular or neural compression. The cause of thoracic outlet syndrome is diverse; however, there are only few reports of thoracic outlet syndrome caused by lipoma in the pectoralis minor space. We report a case of compression of the lower trunk of brachial plexus in which a large lipoma that developed in the pectoral minor space grew into the subclavicular space, along with a review of literature.
Brachial Plexus ; Lipoma ; Nerve Compression Syndromes ; Thoracic Outlet Syndrome

Most cases of spinal subdural hematoma are very rare and result from iatrogenic causes, such as coagulopathy or a spinal puncture. Cases of non-traumatic spinal subdural hematoma accompanied by intracranial hemorrhage are even more rare. There are a few reports of spontaneous spinal subdural hematoma with concomitant intracranial subdural or subarachnoid hemorrhage, but not with intracerebral hemorrhage. Especially in our case, the evaluation and diagnosis were delayed because the spontaneous intracerebral hemorrhage accompanying the unilateral spinal subdural and subarachnoid hemorrhages caused hemiplegia. We report a case of spinal subdural and subarachnoid hemorrhage with concomitant intracerebral hemorrhage, for the first time, with a relevant literature review.
Cerebral Hemorrhage ; Diagnosis ; Hematoma ; Hematoma, Subdural, Spinal ; Hemiplegia ; Intracranial Hemorrhages ; Spinal Puncture ; Subarachnoid Hemorrhage

We describe the case of a patient with an acute subdural hematoma (SDH) that was removed using urokinase irrigation after burr hole trephination in a limited situation where craniotomy was not possible. A 90-year-old woman was admitted to our hospital with a stuporous mental status. Computed tomography (CT) scans revealed a chronic SDH, and a burr hole procedure was performed. The patient's postoperative progression was good until the third day after surgery when we found that the acute SDH had increased on CT scans. The patient's guardian refused further surgery, and thus we drained the blood from the hematoma by injecting urokinase through a drainage catheter. We used urokinase for two days, and removed the catheter after confirming via CT scans that the hematoma was almost alleviated. The patient recovered gradually; she was discharged with few neurological deficits.
Aged, 80 and over ; Catheters ; Craniotomy ; Drainage* ; Female ; Hematoma ; Hematoma, Subdural, Acute* ; Humans ; Stupor ; Tomography, X-Ray Computed ; Trephining ; Urokinase-Type Plasminogen Activator*

Posttraumatic delayed vertebral collapse, known as Kummell’s disease, is increasing in number of patients. This disease is already progressive kyphosis due to vertebral collapse at the time of diagnosis and it causes intractable pain or neurologic deficit due to intravertebral instability. Treatment is very difficult after progression of the disease, and the range of treatment, in hospital day, and cost of treatment are both increased. Clinical features, pathogenesis and radiologic findings of these disease groups were reviewed to determine risk factors for delayed vertebral collapse. The purpose of this article is to suggest appropriate treatment before vertebral collapse for patients with osteoporotic vertebral compression fracture who have risk factors for posttraumatic delayed vertebral collapse.
Diagnosis ; Fractures, Compression ; Humans ; Kyphosis ; Neurologic Manifestations ; Osteonecrosis ; Osteoporosis ; Pain, Intractable ; Risk Factors