• 제목/요약/키워드: Standardized mean difference

검색결과 168건 처리시간 0.026초

Deep Learning-Based Computed Tomography Image Standardization to Improve Generalizability of Deep Learning-Based Hepatic Segmentation

  • Seul Bi Lee;Youngtaek Hong;Yeon Jin Cho;Dawun Jeong;Jina Lee;Soon Ho Yoon;Seunghyun Lee;Young Hun Choi;Jung-Eun Cheon
    • Korean Journal of Radiology
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    • 제24권4호
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    • pp.294-304
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    • 2023
  • Objective: We aimed to investigate whether image standardization using deep learning-based computed tomography (CT) image conversion would improve the performance of deep learning-based automated hepatic segmentation across various reconstruction methods. Materials and Methods: We collected contrast-enhanced dual-energy CT of the abdomen that was obtained using various reconstruction methods, including filtered back projection, iterative reconstruction, optimum contrast, and monoenergetic images with 40, 60, and 80 keV. A deep learning based image conversion algorithm was developed to standardize the CT images using 142 CT examinations (128 for training and 14 for tuning). A separate set of 43 CT examinations from 42 patients (mean age, 10.1 years) was used as the test data. A commercial software program (MEDIP PRO v2.0.0.0, MEDICALIP Co. Ltd.) based on 2D U-NET was used to create liver segmentation masks with liver volume. The original 80 keV images were used as the ground truth. We used the paired t-test to compare the segmentation performance in the Dice similarity coefficient (DSC) and difference ratio of the liver volume relative to the ground truth volume before and after image standardization. The concordance correlation coefficient (CCC) was used to assess the agreement between the segmented liver volume and ground-truth volume. Results: The original CT images showed variable and poor segmentation performances. The standardized images achieved significantly higher DSCs for liver segmentation than the original images (DSC [original, 5.40%-91.27%] vs. [standardized, 93.16%-96.74%], all P < 0.001). The difference ratio of liver volume also decreased significantly after image conversion (original, 9.84%-91.37% vs. standardized, 1.99%-4.41%). In all protocols, CCCs improved after image conversion (original, -0.006-0.964 vs. standardized, 0.990-0.998). Conclusion: Deep learning-based CT image standardization can improve the performance of automated hepatic segmentation using CT images reconstructed using various methods. Deep learning-based CT image conversion may have the potential to improve the generalizability of the segmentation network.

Sodium Citrate가 효과적으로 비전도성 후각장애에 치료효과를 보일 수 있을지에 대한 문헌 고찰 (Can Sodium Citrate Effectively Improve Olfactory Function in Non-Conductive Olfactory Dysfunction?)

  • 김수빈;강하람;진호준;황세환
    • Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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    • 제62권2호
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    • pp.75-81
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    • 2019
  • The objective of this study was to perform a systematic review of the literature for application of intranasal sodium citrate in the patients with olfactory dysfunction to help determine the sodium citrate treatments for this condition. Two authors independently searched the data base (Medline, Scopus, and the Cochrane database) for relevant studies from inception to January 2018. Included studies were randomized controlled studies published in English comparing topical sodium citrate application (treatment group) with saline (control group) in patients who had olfactory dysfunction. Outcomes of interest included the change of olfactory identification and threshold during 2 hours post-treatment. Three studies were enrolled in the meta-analysis. Compared with control group, treatment group did not increase posttreatment score of olfactory identification [standardized mean difference (SMD)=-0.03; 95% confidence interval (CI)=-0.29-0.24; I2=0%] and olfactory threshold (SMD=0.18; 95% CI=-0.09-0.45; I2=0%) significantly. In the degree of pre-post improvement of two outcomes, although treatment group statistically showed the significant improvement in olfactory threshold (SMD=0.30; 95% CI=0.05-0.55; I2=17%), the clinical significance of this outcome was meaningless. Similarly, there was no significant difference in olfactory identification between two groups (SMD=0.17; 95% CI=-0.11-0.45; I2=22%). Unlike the recent favorable results, our summated results presented the uselessness for the local application of sodium citrate in improving patient's olfactory function. However, we also had some limitation such as small sample size and inconsistent application methods. Therefore, larger trials and standardized methodology are needed to reach more stronger and exact results.

Evaluation of Focal Bone Mineral Density Using Three-dimensional Measurement of Hounsfield Units in the Proximal Humerus

  • Moon, Young Lae;Jung, Sung;Park, Sang Ha;Choi, Gwi Youn
    • Clinics in Shoulder and Elbow
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    • 제18권2호
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    • pp.86-90
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    • 2015
  • Background: Although there are several methods for evaluating bone quality, Hounsfield units (HU), a standardized computed tomography (CT) attenuation coefficient, provide a useful tool for estimating focal bone mineral density (BMD). The aim of this study is to investigate the HU for evaluating the degree of osteoporosis in greater tuberosity with regard to anchor positioning. Methods: Forty patients diagnosed as normal on shoulder CT were included and categorized according to age and gender. Axially sectioned CT images were processed to 3-dimensional models containing information about bone quality using Mimics (14.11 platform v14.1.1.1 Materialise). Three-dimensional anchors were simulated and positioned according to 6 regions of interest (ROI) in the greater tuberosity classified using Tingart's system. Mean HU of intra-anchor volumes in the 6 regions was measured. Results: A significant decrease in HU was observed with increasing age (p=0.0001) and menopause (p<0.001). A significant difference in HU was found between male and female groups with males showing the higher values (p=0.0001). HU of proximal areas of ROI was higher than those of distal areas (p<0.005). However, although mean HU of distal posterior ROI showed the lowest values, no statistically significant difference was found between anterior, middle, and posterior regions (p=0.087). Conclusions: Mean HU of ROIs provides a tool for preoperative assessment of focal BMD, which is a factor of suture anchor stability and can be used to aid decision-making regarding secure anchor positioning for rotator cuff repair. Our data support that the most secure point is the proximal regions of ROI.

우리 나라 공무원의 표준화 사망비에 대한 연구 (A SMR study of Korean public servants)

  • 김현경;김용철;백도명
    • Journal of Preventive Medicine and Public Health
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    • 제30권2호
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    • pp.293-307
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    • 1997
  • In Korea, sudden deaths of middle-aged and older male workers who are the responsible persons at home as well as workplace, have aroused social concern. Besides, U. N. has reported recently that mortality of Korea male in 40-50's was one of the highest among newly developed countries in 1992. Not much is, however, known about the nature of the work contributing to the mortality of different groups of workers. Therefore, this study was done to examine mortality of public servants, comprising about 5% of all the employed in Korea, according to their job titles and grades. The datas of 1753 official deaths, comprised 323 (only disease-oriented deaths) applicants of survivors' compensation, were used to examine age-adjusted Standardized Mortality Ratios(SMRs) according to their job titles, grades, tenures and cause of deaths. Controlling age and sex difference was conducted using 26,950,481 general population, 95,340 general deaths and 864,560 working public servants. All the groups were aged 20-64, who were being observed January - December in 1993, at the same time. Results and discussions are as follows. 1. SMRs standardized by general population was significantly low (SMR 44.9 CI 42.8-52.7) for all job titlses. Of public servants, 90.0% was graduated from high school, although 17.5% in general population. The distinction of social status such a education may produce a strong healthy worker effect. Besides, SMRs for different tenure groups showed a steady increase as tenure increases. This suggests that the magnitude of healthy-worker effect may be greater with increasing tenures. 2. SMRs standardized by own public servants was significantly elevated for work-men(SMR 121.0, CI 110.2-132.6) in solitue. When SMRs for different grade, of work-men was examined, 9th(SMR 124.2, CI 104.4-146.7) and 10th(SMR 137.9 CI 120.8-156.8)grade, lower grade in workmen, showed significantly elevated SMRs. Of workmen, 57.0% were graduated from high school and 50.1% in 9th grade, as well. These mean that low economic states made up social class, education may increase mortality rate. 3. Of SMRs according to all causes of death, only policemen on 'cause of death related hypertensive disease'(SMR 282.5, CI 121.6-556.7) was significantly high except for' cause of death related other signs, symptoms and ill-defined conditions'. 4. When SMRs on cause of death related hypertensive disease for different grade of policemen was examined, senior policemen(SMR 241.9), in charge of the front service, showed elevated SMR, in spite of statistical no significance. Especially, the working hour of senior policemen is quite long and also the work schedule is even more irregular for policemen. The results of this study showed that mortality for different jobs differed, and it differed also for different grades in the same job. This difference in mortality may reflect the difference in the nature of job contents, and further studies are warranted to elucidate which job characteristics are responsible.

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새로운 알츠하이머 치료제의 안전성 유효성에 관한 체계적 문헌고찰 (Systemic Literature Review Study on the Efficacy and Safety of Novel Alzheimer's Disease Treatments)

  • 박신웅;장하린;손현순;심미경
    • 한국임상약학회지
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    • 제33권4호
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    • pp.290-304
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    • 2023
  • Background: Innovative Alzheimer's disease drugs received approval in the United States in 2021 and 2023. This study aims to assess the safety and efficacy of these novel treatments, elucidate their mechanisms of action, and compare their impact on cognitive function improvement with approved drugs. Methods: We conducted a comprehensive search of pivotal clinical studies related to Alzheimer's disease treatments in PubMed/Medline, Embase, and the Cochrane Library databases from January 1st, 2020 to December 31st, 2022. Meta-analysis was performed using RevMan 5.4 software. Results: A total of 14 studies were included in this systematic review. When compared to the placebo, the new drugs did not exhibit a statistically significant effect on MMSE (Mini-Mental State Examination) (mean difference= -0.04, 95% confidence intervals [CIs]: -0.31, 0.23, N=3662, I2=0%). However, they demonstrated a significant impact on ADAS-cog (Alzheimer's Disease Assessment Scale-Cognitive Subscale) (standardized mean difference= -0.15, 95% CIs: -0.2, -0.1, N=6710, I2=17%). When compared to the approved drugs, the new drugs showed a statistically significantly lower effect on MMSE (test for subgroup difference Chi2=23.13, N = 5870, p<0.00001) but showed only a trend of decreased efficacy on ADAS-cog (Chi2=1.16, N = 8670, p=0.28). Conclusion: New drugs yielded diverse clinical endpoint results compared to the placebo, and in comparison to existing approved drugs, they exhibited lower efficacy in improving cognitive function. The safety profile of these new drugs, as reported in clinical trials, was generally well-tolerated.

국내 암환자와 관련된 연구논문의 메타분석 - 실험연구를 중심으로 - (An Integrative Review and Meta-analysis of Oncology Nursing Research : 1985-1997.2)

  • 임선옥;홍은영
    • 대한간호학회지
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    • 제27권4호
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    • pp.857-870
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    • 1997
  • The purposes of this study were to describe 12 years of patient-related oncology nursing research in Korea, identifying various nursing interventions, and assesing the effectiveness of the interventions, through analysis and synthesis of the accumulated research papers. One hundred and seventy-nine studies were selected for this study and these were mostly descriptive in design (69.2%). Of the 179 studies, 25 met the criteria for meta-analytic treatment. Twenty-five experimental studies were found in theses and dissertations (68%), 92% used convenience sample, and the median sample size was 40. Subjects were predominantly in treatment and rehabilitation (76%). Most studies(68%) were not derived from a theory base, with only 8% reporting use of a nursing theory. Results of the meta-analysis are as follows. The effect size of the nursing intervention type was found to be significantly effective. The standardized mean difference ranged from a high positive of 2.55 to a low negative of -0.22. Direct personal nursing intervention method was more effective than indirect group method. Two nursing intervention methods were more effective than one. The greatest effect size was thyxical intervention. The greatest mean effect size was scalp hypothermia technique. Teaching was a frequent intervention after 1990, although a wide range of treatments were studied. Effect size of intervention for symptom management was largest in relieving pain. Effective intervention method for relieving anxiety was exercise.

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Core Skill-TLP가 임상수행능력 향상에 미치는 효과 (The Effect of Clinical Performance Improving by Application of Core Skill-TLP)

  • 황현숙
    • 대한물리의학회지
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    • 제7권2호
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    • pp.231-239
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    • 2012
  • Purpose : The purpose of this study is to investigate the effect of clinical performance improved by the application of the Core-Skill TLP to students. Methods : The subject of the study were 48 students who are enrolled in the 2nd semester of the 3rd year in the department of physical therapy. In order to compare the difference in physical examination and intervention, clinical practice integration as well as interpersonal communication skills were measured before and after clinical performance experiments by using the questionnaire. Result : The results are as follows. There was an improvement after examination & intervention about mean 1.52(t=16.928, p=.000), in clinical practice integration 1.30(t=14.541, p=.000) and in interpersonal communication skills 0.86(t=9.510, p=.000). It shows the significant difference in statistics. Conclusion : According to these results, the Core-Skill TLP is proved as a good learning strategy and could be strongly recommended since it significantly improved physical examination & intervention, clinical practice integration and interpersonal communication skills.

No evidence on the effectiveness of oral splints for the management of temporomandibular joint dysfunction pain in both short and long-term follow-up systematic reviews and meta-analysis studies

  • Fouda, Atef Abdel Hameed
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제46권2호
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    • pp.87-98
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    • 2020
  • The aim of this study was to determine the efficacy of oral splints in reducing the intensity of pain in patients with temporomandibular joint dysfunction in both short and long-term treatment durations. Electronic databases, Cochrane Library, MEDLINE via PubMed, Web of Science, Egyptian Knowledge Bank, and EMBASE were searched for randomized controlled trials comparing different types of splints to non-occluding splints, behavioral therapy, pharmacotherapy, counseling, and no treatment. The risk of bias was assessed by using Cochrane risk of bias recommendations. Fixed and random effects were used to summarize the outcomes. The effect estimates were expressed as standardized mean differences (SMD) or risk ratios with a 95% confidence interval (CI). Subgroup analyses were carried out according to the treatment duration. Twenty-two studies met the inclusion criteria. A meta-analysis of short-term studies up to three months revealed no significant difference between the study groups. However, long-term studies exhibited a significant difference in pain reduction in favor of the control group. Total analysis revealed that the control group resulted in significant pain reduction (SMD 0.14, 95% CI 0.05-0.23, P=0.002, I2=0%). Oral splints are not effective in reducing pain intensity or improving function in patients with temporomandibular joint dysfunction.

디지털 방사선 촬영술을 이용한 치근 흡수 판독에 관한 실험적 연구 (AN EXPERIMENTAL STUDY ON THE TOOTH ROOT RESORPTION FOR DIGITAL RADIOGRAPHY)

  • 오필교;김재덕
    • 치과방사선
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    • 제25권2호
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    • pp.375-387
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    • 1995
  • The purpose of this study was to quantitatively evaluated experimental tooth root resorption for digital radiography. For this study, experimentally three root sites were used, and radiograms were taken with standardized apparatus. Digital imaging system were consisted of NEC PC-980l(computer), TRINITRON(monitor), SONY XC-711 CCD camera. The display monitor had a resolution of 512X512 pixels. The obtained results were as follows: 1. In the difference of the four X-ray film of the contrast correction, the contrast difference was one gray scale variation at mean value. 2. Viewing of the view box of the periapical radiographs, experimental tooth root resorption of the periapical area of the first premolar, middle of mesial surface of the first molar mesial root, middle of lingual surface of the first molar distal root were recognized by increased diameter. 3. On the analysis by histogram, the periapical area of the first premolar, the middle of mesial surface of the first molar mesial root were each recognized tooth root resorption of the 5,6,7 pixel, 2,4,5 pixel by increased diameter. 4. On the analysis by histogram, the middle of lingual surface of the first molar distal root was each recognized tooth root resorption of the none, 3,6 pixel by increased diameter.

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노인요양시설에서 활용되는 간호중재의 중요도와 수행도 분석 (The Importance and Performance of Nursing Interventions Perceived by Nurses in Long-term Care Facilities for Elderly)

  • 김영애;황혜영;박현태
    • 간호행정학회지
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    • 제12권2호
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    • pp.189-195
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    • 2006
  • Purpose: This study was to identify nursing interventions which were perceived highly in the importance and performance of nursing interventions by nurses in long-term care facilities for elderly. Method: Data was collected from nurses working in long-term care facilities for elderly over 2 years who participated in continuous education by Korea Association of Senior Citizens Welfare Institution. Data was analyzed using mean and paired t-test to compare difference between the importance and performance of each nursing intervention. Results: Among 264 nursing intervention, 49 nursing interventions were considered highly important and performed very often by nurses. Especially, 11 nursing interventions had significant difference between the importance and the performance, which meant that nurses perceived them as the most important and they were not implemented often as much as that by nurses. Conclusion: The results of this study revealed that what kinds of the nursing interventions were perceived highly important and performed very often by nurses in long-term care facilities for elderly. These nursing interventions can be utilized in the development of standardized nursing intervention classification to be used for the long-term care facilities for elderly.

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