• Korean Journal of Radiology
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• v.22 no.3
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• pp.442-453
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• 2021

Artificial intelligence (AI) will likely affect various fields of medicine. This article aims to explain the fundamental principles of clinical validation, device approval, and insurance coverage decisions of AI algorithms for medical diagnosis and prediction. Discrimination accuracy of AI algorithms is often evaluated with the Dice similarity coefficient, sensitivity, specificity, and traditional or free-response receiver operating characteristic curves. Calibration accuracy should also be assessed, especially for algorithms that provide probabilities to users. As current AI algorithms have limited generalizability to real-world practice, clinical validation of AI should put it to proper external testing and assisting roles. External testing could adopt diagnostic case-control or diagnostic cohort designs. A diagnostic case-control study evaluates the technical validity/accuracy of AI while the latter tests the clinical validity/accuracy of AI in samples representing target patients in real-world clinical scenarios. Ultimate clinical validation of AI requires evaluations of its impact on patient outcomes, referred to as clinical utility, and for which randomized clinical trials are ideal. Device approval of AI is typically granted with proof of technical validity/accuracy and thus does not intend to directly indicate if AI is beneficial for patient care or if it improves patient outcomes. Neither can it categorically address the issue of limited generalizability of AI. After achieving device approval, it is up to medical professionals to determine if the approved AI algorithms are beneficial for real-world patient care. Insurance coverage decisions generally require a demonstration of clinical utility that the use of AI has improved patient outcomes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.209-214
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• 2006

This study is validity study of the questionnaire for doctors for Sasang constituion diagnosis. (an objects of this study : 314 patients) We analyzed the results of questionnaires about 314 patients who were diagnosed in Department of Sasang Constitutional Medicine from June to November, 2004. The questionnaire for doctors consists of objective valuation about the patients for Sasang constituion diagnosis. In the analysis about all variables, we obtain the diagnosis accuracy of 92%. In the analysis about body type variable, we obtain the diagnosis accuracy of 44-48%. In the analysis about external appearance, mental characteristics, physiology & pathologic symptoms variables, we obtain the diagnosis accuracy of 46-72%. After all, in order to increase of the diagnosis accuracy, we have to analysis total variables(body type, external appearance, mental characteristics, physiology & pathologic symptoms) for sasang constituion diagnosis. Hereafter, We need many data and standardization for sasang constituion diagnosis.

• Journal of the Korea Concrete Institute
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• v.15 no.4
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• pp.625-633
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• 2003

For the construction of open-topped steel box girder bridges, prefabricated concrete slab could offer several advantages over cast-in-situ deck including good quality control, fast construction, and elimination of the formwork for concrete slab casting. However, precast decks without reinforcements at transverse joints between precast slabs should be designed to prevent the initiation of cracking at the joints, because the performance of the joint is especially crucial for the integrity of a structural system. Several prestressing methods are available to introduce proper compression at the joints, such as internal tendons, external tendons and support lowering after shear connection. In this paper, experimental results from a continuous composite bridge model with precast decks are presented. Internal tendons and external tendons were used to prevent cracking at the joints. Judging from the tests, precast decks in negative moment regions have the whole contribution to the flexural stiffness of composite section under service loads if appropriate prestressing is introduced. The validity of the calculation of a cracking load fur serviceability was presented by comparing an observed cracking load and the calculated value. Flexural behavior of the continuous composite beam with external prestressing before and after cracking was discussed by using the deflection and strain data.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.5
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• pp.123-134
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• 2007

A method to determine the initial force of external tendon is proposed to improve the load carrying capacity in existing steel-concrete composite bridges. This method is applied to tensioning external tendons prior to and after concrete replacement for strengthening composite girders. A procedure to determine the number of tendon and initial tendon force is described with the proposed rating factor, which considers the increment of tendon force due to live loads. The method is applied to the improvement of rating factor in an existing composite bridge and its validity is confirmed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.2
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• pp.115-126
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• 2015

The purpose of this paper is to explore the strategy of future Korean medicine(KM) clinical research through the study on the proposals for KM clinical research worldwide. In this study, the papers published in English through Pubmed were investigated mainly. Among them, we analyzed the methodological proposals from the clinical research papers that were published in the KM related fields. Various proposals for improving the problems in KM clinical studies are as follows. First, KM clinical research should be designed based on understanding for the theory, backgrounds, paradigms and worldviews of KM. In addition, considering the model validity, KM clinical research model should include the diagnosis, interventions and outcomes measurement methods reflecting the characteristics and real practice in KM. The internal validity and external validity should be also taken into account. One of the most important thing is to identify the contents about various and complex 'real practice' in KM. A prospective observational study was suitable for the purpose of this study. Finally, we suggested a few improvement directions for RCTs studies in KM. First, we would be able to improve the quality and the internal validity in KM clinical research using the checklists of CONSORT(Consolidated Standards for Reporting Trials) Statement and STRICTA(Standards for Reporting Interventions in Clinical Trials of Acupuncture). Second, we could use various clinical research methods and the modified research of RCTs such as PCT(pragmatic clinical trial) to reflect the characteristics of actual KM practice. Consequently, we would be able to improve the external validity. Third, the KM diagnosis and outcomes measurement methods should be developed based on an actual KM practice and it should reflect a real practice. The 'pattern identification(辨證)' is the core to KM diagnosis. But in order to be applied to the clinical research, the pattern identification(辨證) should be objectified and standardized. Future KM clinical research model should reflect the characteristics and a real practice in KM. In addition, it should include the advantage of rigorous RCTs research.Specially, the diagnosis, interventions and outcomes measurement methods in KM clinical research should reflect this view.

• Journal of Technology Innovation
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• v.6 no.1
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• pp.163-186
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• 1998

The psychological work environments which facilitate technology innovations in organizations are divided into two dimensions of supportive work environments and uncertain work environments. The measurement variables have significant reliability. And the confirmatory factor analysis confirm the construct validity of two dimensional work environments. Two work environments have the significant effects on motivations to the technology innovations. So, simple and hierarchical regression analyses confirm criterion-related validity. Therefore, Both of the uncertain work environments(uncertainty of external-organizational environments and tasks) and the two important work environments(supporting idea, resource supply, job autonomy) are the two important psychological work environments which indicate technology innovations in organizations. Measures for innovative psychological work environments are provided.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.9-12
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• 1993

This study investigated the propriety and the extension of the term of validity about the using watthour meters at present. The subject of study is 1Cent 2W 220V 30(10)A, 1Cent 3W 110V 30(10)A of model III watthour meters. They are the used metes(products in 1984) and the repaired meters(products in 1977) in the end of the period. The investigation is as follows. o Investigation of external appearance o Driving current test o Creeping test o Noise test o Error test o Durability test. Results of the study have been the number of 13.3% exceeded permitting error and the number of 31.3% failed in endurable test of 500 hours. So, the using meters are not suitable to extend the term of validity without the improvement of several characteristics.

• Health Policy and Management
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• v.26 no.2
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• pp.148-152
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• 2016

The hospital readmission rate has been widely used as an indicator of the quality of hospital care in many countries. However, the transferrability of this indicator that has been developed in a different health care system can be questioned. We reviewed what should be considered when using the risk-standardized readmission rate (RSRR) as a generic quality indicator in the Korean setting. We addressed the relationship between RSRR and the quality of hospital care, methodological aspects of RSRR, and use of RSRR for external purposes. These issues can influence the validity of the readmission rate as a generic quality indicator. Therefore RSRR should be used with care and further studies are needed to enhance the validity of the readmission rate indicator.

• Journal of Korean Academy of Nursing
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• v.32 no.3
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• pp.395-405
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• 2002

The purpose of this study was to develop the instrument to measure family functioning for Korean family with a chronic ill child, and to test the validity and reliability of the instrument. Method: The items of instrument were consisted based on researchers' previous study of concept analysis of the Korean family functioning. Twenty six item scale was developed with six domains. In order to test reliability and validity of the scale, data were collected from the 231 families, who have a child with a chronic illness. Data was collected between August and September in 2001 in a General Hospital in Seoul, Korea. Result: The results were as follows: As a result of the item analysis, 24 items were selected from the total of 26 items, excluding items with low correlation with total scale. Six factors were evolved by factor analysis. Six factors explained 61.4% of the total variance. The first factor 'Affective bonding' explained 15.4%, 2nd factor 'External relationship' 11.8%, 3rd factor 'Family norm' 10.5%, 4th factor 'Role and responsibilities' 8.3%, 5th factor ' Communication' 7.9%, and the 6th factor 'Financial resource' explained 7.3%. Cronbach's $\alpha$ coefficient of this scale was .87 and Guttman spilt- half coefficient was .84. Conclusion: The study support the reliability and validity of the scale. There were distinct differences in dimensions of family functioning scales developed in the U. S.

• 모자간호학회지
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• v.3 no.2
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• pp.85-94
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• 1993

The purpose of this study was to test the construct validity and reliability of the Health Self-Determinism Index for Children (HSDI-C), an instrument designed to measure intrinsic motivation in health behavior. An convenience sample of 558,7 to 13 years old children completed the Korean version of HSDI-C. The findings were as follows : 1. Construct validity was supported through factorial isolation of four theory-consistent subscales ; Internal-external cue responsive ness, Self-determinism in health judgement, Competency in health matters, and Self-determinism in health behavior /goal. The total percent of variance explained by 4 factors was 2 percent. 2. The correlations between the four factors were ranged from -.06 to .29 indicating that factors are not redundant and each factor contributes uniquely to the total construct. 3. Cronbach alpha coefficient for internal consistency was .96 for the total, and .72, .56, .69, and .75 on the respective subscales. Test-retest reliability for the total scale was .85 at 2 weeks. 4. The Analysis of variance for the HSDI-C total scale and subscales according to grades revealed that there were significant differences in means for the total and factor one and two, indicating younger children were more extrinsically motivated.