• 제목/요약/키워드: Retrospective Statistical Analysis

검색결과 272건 처리시간 0.031초

A New Approach to the Science Education Assessment Using Partial Credits to Different Science Inquiry Problem Solving Process Types

  • Lee, Hang-Ro;Lim, Cheong-Hwan
    • 한국지구과학회지
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    • 제23권2호
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    • pp.147-153
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    • 2002
  • Reasonable and reliable assessment method is one of the most important issues in science education, Partial credits method is an effective tool for assessing students' science inquiry problem solving. The purposes of this study were to classify the Problem solving types based on the analysis of the thinking Process, and how much the related science concept and the science process skills were used in solving science inquiry problems, and to describe the possibility and rationality of the assessment method that gives partial credit 128 high school seniors were selected and their answers were analyzed to identify science concepts they used to solve each problem, and the result was used as the criterion in the scientific concept test development. Also, to study the science inquiry problem solving type, 152 high school seniors were selected, and protocols were made from audio-taped data of their problem solving process through a think-aloud method and retrospective interviews. In order to get a raw data needed in statistical comparison of reliability, discrimination and the difficulty of the test and the production of the regression equation that determines the ratio of partial credit, 640 students were selected and they were given a science inquiry problem test, a science process skills test, and a scientific concept test. Research result suggested it is more reasonable and reliable to switch to the assessment method that applies partial credit to different problem solving types based on the analysis of the thinking process in problem solving process, instead of the dichotomous credit method.

Magnetic Resonance Imaging-Based Volumetric Analysis and Its Relationship to Actual Breast Weight

  • Yoo, Anna;Minn, Kyung Won;Jin, Ung Sik
    • Archives of Plastic Surgery
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    • 제40권3호
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    • pp.203-208
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    • 2013
  • Background Preoperative volume assessment is useful in breast reconstruction. Magnetic resonance imaging (MRI) and mammography are commonly available to reconstructive surgeons in the care of a patient with breast cancer. This study aimed to verify the accuracy of breast volume measured by MRI, and to identify any factor affecting the relationship between measured breast volume and actual breast weight to derive a new model for accurate breast volume estimation. Methods From January 2012 to January 2013, a retrospective review was performed on a total of 101 breasts from 99 patients who had undergone total mastectomy. The mastectomy specimen weight was obtained for each breast. Mammographic and MRI data were used to estimate the volume and density. A standard statistical analysis was performed. Results The mean mastectomy specimen weight was 340.8 g (range, 95 to 795 g). The mean MRI-estimated volume was $322.2mL^3$. When divided into three groups by the "difference percentage value", the underestimated group showed a significantly higher fibroglandular volume, higher percent density, and included significantly more Breast Imaging, Reporting and Data System mammographic density grade 4 breasts than the other groups. We derived a new model considering both fibroglandular tissue volume and fat tissue volume for accurate breast volume estimation. Conclusions MRI-based breast volume assessment showed a significant correlation with actual breast weight; however, in the case of dense breasts, the reconstructive surgeon should note that the mastectomy specimen weight tends to overestimate the volume. We suggested a new model for accurate breast volume assessment considering fibroglandular and fat tissue volume.

액취증의 치료에서 Inaba씨 방법과 절개창을 지연 봉합한 Inaba씨 변법의 비교 조사 (Comparative Study Between Inaba's Procedure and Modified Inaba's Procedure with Delayed Suture in the Treatment of Osmidrosis Axillae)

  • 이성표;석정훈;양완석
    • Archives of Plastic Surgery
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    • 제36권6호
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    • pp.727-734
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    • 2009
  • Purpose: The Inaba's procedure, the treatment of osmidrosis axillae, has the advantages of low recurrent rate and easy to learn, yet it produces early postoperative discomfort and scar formation by tie - over dressing. The authors modified the Inaba's procedure by using delayed suture of the incision wound and omitting tie - over dressing. The comparative study of Inaba's procedure and its modification was performed to confirm the advantages of modified procedure. Methods: The study contains the retrospective analysis of the medical records of 296 patients with osmidrosis who were treated using the Inaba's procedure from December, 1996 to February, 2007. The study also contains the prospective analysis of 20 patients, from March, 2007 to July, 2008, who were treated by the modified Inaba's procedure with delayed suture of the incision wound and gentle pressure dressing instead of tie - over dressing. The operative results of two groups were compared and verified by Mann - Whitney U test(SPSS 12.0). Results: The incidence of complications was 14.5% in the Inaba's procedure, whereas 6.2% in the modified Inaba's procedure. Both procedures have the same basic surgical procedure in terms of the location of incision site and subdermal shaving of the sweat glands, and therefore similar good results were obtained in the aspect of postoperative axillary odor, recurrent rate and postoperative condition of axillary hair. Certainly, the modified Inaba's procedure had better outcome in each element of PSS(Patient Scar Self-Rating Scale), compared to the Inaba's procedure. In addition, the modified Inaba's procedure showed a statistical significance in dressing - related pain reduction and overall satisfaction. Conclusion: The modified Inaba's procedure had advantages of decreased early postoperative complications such as hematoma, discomfort and pain caused by tie - over dressing, and decreased scar formation. However, the drawback was delayed suture of the incision wound after 48 hours.

Does Low-Dose Heparin Have a Significant Role in Free Flap Surgery?

  • An, Mun-Young;Shin, Jin Yong;Lee, Young-Keun;Sabbagh, M. Diya;Roh, Si-Gyun;Lee, Nae-Ho
    • 대한두개안면성형외과학회지
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    • 제18권3호
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    • pp.162-165
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    • 2017
  • Background: It is controversial issue that heparin decreases thrombosis for microsurgical anastomosis, and its effective role is under discussion. This study is for proving whether low-dose heparin is preventing thrombosis in free flap reconstruction. Methods: Through chart reviews of 134 patients, using low-dose heparin for free tissue transfer from 2011 to 2016, retrospective analysis was performed. 33 patients received low-dose heparin therapy after surgery. And 101 patients received no-heparin therapy. Complications included flap necrosis, hematoma formation, dehiscence and infection. Results: In no-heparin therapy group, comparing the flap necrosis revealed 16 cases (15.84%). And, flap necrosis was 6 cases (18.18%) in low-dose heparin therapy group. The statistical analysis of flap necrosis rate showed no significant difference (p=0.75). The results showed that there was no significant difference of flap necrosis rate between two groups. Conclusion: In this study, patients in the low-dose heparin group had no significantly lower rates of flap failure compared with no-heparin group. This suggests that low-dose heparin may not prevent thrombosis and subsequent flap failure to a significant extent.

Radiographic evaluation of the maxillary sinus prior to dental implant therapy: A comparison between two-dimensional and three-dimensional radiographic imaging

  • Tadinada, Aditya;Fung, Karen;Thacker, Sejal;Mahdian, Mina;Jadhav, Aniket;Schincaglia, Gian Pietro
    • Imaging Science in Dentistry
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    • 제45권3호
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    • pp.169-174
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    • 2015
  • Purpose: This study was performed to evaluate the diagnostic efficacy of panoramic radiography and cone-beam computed tomography (CBCT) in detecting sinus pathology. Materials and Methods: This study was based on a retrospective evaluation of patients who had undergone both a panoramic radiograph and a CBCT exam. A total of 100 maxillary sinuses were evaluated. Four examiners with various levels of expertise evaluated the images using a five-point scoring system. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficacy of the two modalities. The image analysis was repeated twice, with at least two weeks between the evaluation sessions. Interobserver reliability was assessed using Cronbach's alpha, and intraobserver reliability was assessed using Cohen's kappa. Results: Maxillary sinus pathology was detected in 72% of the patients. High interobserver and intraobserver reliability were observed for both imaging modalities and among the four examiners. Statistical analyses using ROC curves demonstrated that the CBCT images had a larger area under the curve (0.940) than the panoramic radiographs (0.579). Conclusion: Three-dimensional evaluation of the sinus with CBCT was significantly more reliable in detecting pathology than panoramic imaging.

Relationship between squamous cell carcinoma of the tongue and the position of dental prosthesis

  • Fan, Huan;Yoon, Ki-Yong;Kim, Soung-Min;Myoung, Hoon;Lee, Jong-Ho;Kim, Myung-Jin
    • The Journal of Advanced Prosthodontics
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    • 제7권2호
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    • pp.129-137
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    • 2015
  • PURPOSE. Squamous cell carcinoma (SCC) of the tongue has a relatively high incidence of all oral cancers. Some studies have reported a relationship between intraoral dental prosthesis and SCC of the tongue; however, this relationship remains controversial. The purpose of this study was to investigate the relationship between SCC of the tongue and the positional aspects of dental prosthesis using a retrospective analysis. MATERIALS AND METHODS. A total of 439 patients with SCC of the tongue were diagnosed and treated in the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Patients were treated over a 12.5-year period ranging from January 1, 2001 to June 30, 2013. Statistical analysis was performed to examine potential differences between the groups. RESULTS. The number of patients with a crown and/or a bridge (134, 63.5%) was significantly different than the number of patients without a prosthesis (77, 36.5%). Even after accounting for different types of prostheses such as crowns, bridges, and dentures, no significant differences were observed between the position of the prosthesis and the location of the SCC of the tongue, with significance defined as a P-value less than .05 by the Pearson-Chi square test. CONCLUSION. Patients with crowns and/or bridges exhibited more frequent SCC of the tongue compared with patients without these prosthesis. These data support the hypothesis that mechanical trauma and galvanic phenomena play a role in the etiology of SCC of the tongue.

A Retrospective Comparative Study of Serbian Underground Coalmining Injuries

  • Ivaz, Jelena S.;Stojadinovic, Sasa S.;Petrovic, Dejan V.;Stojkovic, Pavle Z.
    • Safety and Health at Work
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    • 제12권4호
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    • pp.479-489
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    • 2021
  • Background: During 2011, a study was undertaken to assess safety conditions in Serbian underground coalmines by analysis of injury data. The study covered all Serbian coalmines, identified week spots from the aspect of safety, and recommended possible courses of action. Since then, Serbia has made changes to safety and health legislation; all coalmines introduced new preventive measures, adopted international standards, and made procedures for risk management. After 10 years a new study has been performed to analyze the impact of these changes. Materials and methods: In this study, the injuries that have occurred in the Serbian underground coal mines over the last 20 years were analyzed. Statistical data analysis was performed by IBM SPSS Statistics v23. The injuries that occurred in the last ten years were compared with the results of the previous study (2000-2009). The average values of injury rates for both periods were compared for each of the categories (severity, age, body part, qualification), and the results were presented as absolute difference or percentile difference. Results: The results showed reduction in the number of injuries in the category of 20-30 years old workers, where the new training procedures for workers, which were set by mandatory legal regulations, certainly contributed. They also showed an increase in the number of injuries in the category of old workers, which indicates that the law did not have a positive effect on this category. Conclusion: The total number of injuries is still high; therefore, it is necessary to introduce mechanization and automation in mines and have a better policy for older workers who retire later nowadays.

부인과 수술 후 한방 조기 회복 치료를 받은 입원 환자에 대한 후향적 분석 (Traditional Korea Medicine for Enhanced Recovery after Surgery (ERAS) in Inpatients after Gynecological Surgery: Retrospective Analysis)

  • 김혜원;유정은
    • 대한한방부인과학회지
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    • 제32권3호
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    • pp.142-161
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    • 2019
  • Objectives: The purpose of this study is to report the effect and safety of traditional Korean medicine (TKM) for enhanced recovery after surgery (ERAS) after gynecological surgery. Methods: The study is conducted by analyzing the medical records of the hospitalized patients in TKM hospital. Eighty-six patients were enrolled who received TKM for ERAS after gynecological surgery from January 2015 to April 2018. We performed statistical analysis by using SPSS ver. 25.0. To prove the effect and safety of TKM for ERAS, we analyzed symptoms and Hemoglobin (Hb), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and serum creatinine (Cr) with glomerular filtration rate (GFR). In addition, we checked other adverse reactions that the patients complained to prove the safety of TKM for ERAS. Results: Among symptoms of pain, there was a statistically significant decrease in abdominal pain, lower back pain, and shoulder pain. Other symptoms showed statistically significant improvement in fatigue, abdominal tympanosis, operation-site discomfort, dizziness, urinary discomfort, throat discomfort, constipation, dyspepsia and colporrhagia. Anemia in both ferritin combination treatment group and herbal medicine only group showed significant improvement. There was no liver damage or renal damage by TKM. Conclusions: The result has shown that TKM for ERAS after gynecological surgery is effective and safe. The further study of TKM for ERAS with more patients is needed.

Intracorporeal Esophagojejunostomy Using a Circular or a Linear Stapler in Totally Laparoscopic Total Gastrectomy: a Propensity-Matched Analysis

  • Kang, So Hyun;Cho, Yo-Seok;Min, Sa-Hong;Park, Young Suk;Ahn, Sang-Hoon;Park, Do Joong;Kim, Hyung-Ho
    • Journal of Gastric Cancer
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    • 제19권2호
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    • pp.193-201
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    • 2019
  • Purpose: There is no consensus on the optimal method for intracorporeal esophagojejunostomy (EJ) in laparoscopic total gastrectomy (LTG). This study aims to compare 2 established methods of EJ anastomosis in LTG. Materials and Methods: A total of 314 patients diagnosed with gastric cancer that underwent LTG in the period from January 2013 to October 2016 were enrolled in the study. In 254 patients, the circular stapler with purse-string "Lap-Jack" method was used, and in the other 60 patients the linear stapling method was used for EJ anastomosis. After propensity score matching, 58 were matched 1:1, and retrospective data for patient characteristics, surgical outcome, and post-operative complications was reviewed. Results: The 2 groups showed no significant difference in age, body mass index, or other clinicopathological characteristics. After propensity score matching analysis, the linear group had shorter operating time than the circular group ($200.3{\pm}62.0$ vs. $244.0{\pm}65.5$, $P{\leq}0.001$). Early postoperative complications in the circular and linear groups occurred in 12 (20.7%) and 15 (25.9%, P=0.660) patients, respectively. EJ leakage occurred in 3 (5.2%) patients from each group, with 1 patient from each group needing intervention of Clavien-Dindo grade III or more. Late complications were observed in 3 (5.1%) patients from the linear group only, including 1 EJ anastomosis stricture, but there was no statistical significance. Conclusions: Both circular and linear stapling techniques are feasible and safe in performing intracorporeal EJ anastomosis during LTG. The linear group had shorter operative time, but there was no difference in anastomosis complications.

Relationship between needle depth for lumbar transforaminal epidural injection and patients' height and weight using magnetic resonance imaging

  • John, Hyunji;Sohn, Kyomin;Kim, Jae Hun
    • The Korean Journal of Pain
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    • 제35권3호
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    • pp.345-352
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    • 2022
  • Background: Optimal needle depth in transforaminal epidural injection (TFEI) is determined by body measurements and is influenced by the needle entry angle. Physician can choose the appropriate needle length and perform the procedure more effectively if depth is predicted in advance. Methods: This retrospective study included patients with lumbosacral pain from a single university hospital. The skin depth from the target point was measured using magnetic resonance imaging transverse images. The depth was measured bilaterally for L4 and L5 TFEIs at 15°, 20°, and 25° oblique angles from the spinous process. Results: A total of 4,632 measurements of 386 patients were included. The lengths of the left and right TFEI at the same level and oblique angle were assessed, and no statistical differences were identified. Therefore, linear regression analysis was performed for bilateral L4 and L5 TFEIs. The R-squared values of height and weight combined were higher than the height, weight, and body mass index (BMI). The following equation was established: Depth (mm) = a - b (height, cm) + c (weight, kg). Based on the equation, maximal BMI capable with a 23G, 3.5-inch, Quincke-type point spinal needle was presented for three different angles (15°, 20°, and 25°) at lumbar levels L4 and L5. Conclusions: The maximal BMI that derived from the formulated equation is listed on the table, which can help in preparations for morbid obesity. If a patient has bigger BMI than the one in the table, the clinician should prepare longer needle than the usual spinal needle.