• International Journal of Reliability and Applications
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• v.17 no.1
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• pp.51-63
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• 2016

Stress function of ball bearing is function of multiple stochastic factors and this system is so complex that analytical expression for reliability is difficult to obtain. To address this pressing problem, in this article, we have made an attempt to approximate system reliability of this important item based on reliability bounds under the stress strength setup. This article also provides level of error of this item. Numerical analysis has been adopted to show the closeness between the upper and lower bounds of this item.

• Journal of Korean Physical Therapy Science
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• v.18 no.3
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• pp.53-61
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• 2011

Purpose : his study was to analyze the reliability and validity on Oswestry Low Back Pain Disability Index (OLBPDI) in patients with low back pain. Methods : The sample consisted of 211 patients who had received treatments at the physical therapy units of 3 medical institutions from February to December 2008 in Andong city. Questionnaires on the OLBPDI were recruited by 6 physical therapists. The internal structure and reliability of the scales were evaluated by means of item-internal consistency(Cronbach's alpha coefficient:${\alpha}$), item-discriminant validity, Pearson's relation coefficient. Results : An average of patients's age was 41.1 years. The range of OLBPDI subscales were .93~.94 in Cronbach's ${\alpha}$. The internal consistency reliability of total item-each item were also internally consistent with Cronbach's ${\alpha}$ range of .94~.95(Pearson's correlation coefficient range: .62~.89). However, high correlation were obtained among 10 items(.67~.83), therefore the item-discriminant validity was a little low. Conclusion: In conclusion, the results reported here confirm the reliability of the OLBPDI scales in patients with low back pain. The collection of information on the level of disability due to low back pain using this instrument was acceptable to patients. A further prospective multi-center study will be necessary to prove the reliability and validity.

• Korean Journal of Oriental Medicine
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• v.13 no.1 s.19
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• pp.109-114
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• 2007

The high position condition 10 escape which the obesity person appeals. Obesity Pattern-Identification question it will yell and 243 subjects which to the obesity in the patient of 517 subjects which draw up correspond. (longitude obesity 153 person, altitude obesity 90 person) against it analyzes. In order to analyze the reliability of the items which diagnose each Pattern-Identification it used Cronbach alpha coefficient and escape it did the alpha of each item. Alpha value of each Pattern-Identification than appears more highly the item which it will be able to consider an elimination in the item which decreases a reliability. In that phlegm-retention syndrome is bigger alpha coefficient 0.784 than 'meal quantity is few'(0.787) a possibility of seeing in the item which decreases a reliability to the place where it diagnoses it puts in phlegm-retention syndrome.

• Journal of the military operations research society of Korea
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• v.10 no.2
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• pp.61-73
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• 1984

A block replacement policy using items with different reliability is discussed. We divide system unit failure modes into two modes and use less reliable unit when operating unit fails near the planned preventive replacement time. In this policy, item A has two failure modes. Mode-1 failure is removed by minimal repair, mode-2 failure by replacement. If mode-2 failure of item A happens in (0, $T-{\delta}$), failure item A is replaced by new item A. If mode-2 failure of item A happens in ($T-{\delta}$, T), failure item A is replaced by new item B. Item B should be cheaper and less durable than item A. Under this policy, we determine the preventive replacement interval $T^{*}$ and the interval ${\delta}^{*}$ of item B replacement which minimize the cost rate per unit time.

• Journal of Applied Reliability
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• v.12 no.3
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• pp.131-138
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• 2012

A design of reliability qualification test based on performance distribution is developed. In general, the performance of an item degrades as the time goes by and the failure of an item occurs when the performance degradation reaches the pre-determined critical level. This article considers the reliability qualification test based on a more tightened critical value at the earlier stage to reduce the evaluation testing time and cost. A numerical example is provided to illustrate how to use the developed reliability qualification test.

• Research in Community and Public Health Nursing
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• v.11 no.1
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• pp.199-208
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• 2000

The purpose of this study is to test the psychometric properties of the Korean version of the Health-Related Hardiness Scale(HRHS) in a sample of Korean nursing students. The korean version of HRHS was administered to 234 nursing students including 135 college students and 99 university students. The Korean version of HRHS was measured on a 6 Likert scale, assessing three factors of HRHS : control, commitment, and challenge. Internal consistency was used to test the instrument's reliability. The internal consistency of the scale was measured using a coefficient alpha. The coefficient alpha was .69(control), .49(commitment). and .69(challenge), Item analysis and confirmatory factor analysis (CFA) were used to test the instrument's construct validity. The item analysis identified that there were 13 items. which were lower than the .25 item-total correlation. CFA revealed that the scale's fadoral validity was not proper by showing unfit indices(RMSEA .07. stand, RMR .09. GFI .71). According to the findings of this study, the reliability and construct validity of the Korean version of HRHS is not satisfactory in the sample of nursing students. As a result. the researcher modified the scale through item analysis and repetitive CFA process, and proposed the revised 25-item Korean version of HRHS for nursing students. The revised scale's reliability(control .74, commitment .73. challenge .77) and factorial validity were within acceptable levels. The item analysis identified that there was no item, which is lower than the .25 item-total correlation. CFA revealed that the scale's factoral validity was proper by showing fit indices(RMSEA .08 stand. RMR .08. GFI .80).

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.192-197
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• 2020

Foreign students in South Korea face important challenges when they try to maintain their health. As a measure of their motivation to actively build skills for overcoming those challenges, we evaluated the 10-item Consumer Health Activation Index (CHAI), testing its feasibility, dimensionality, and reliability. There were no missing data, there was no floor effect, and for the total scores the ceiling effect was trivial (< 2%). Results of the Kaiser-Meyer-Olkin test and Bartlett's test of sphericity indicated that the data were suitable for the detection of structure by factor analysis. The results of parallel analysis and the shape of the scree plot supported a two-factor solution. One factor had 3 items concerning "my doctor" and the other factor had the 7 remaining items. Reliability was high for the 10-item CHAI (alpha = 0.856), for the 3-item subscale (alpha = 0.838), and for the 7-item subscale (alpha = 0.857). Reliability could not be improved by deletion of any items. Use of the CHAI to gather data from these foreign students is feasible, and reliable results can be obtained whether one uses the total score from all 10 items or scores from the proposed 7-item and 3-item subscales.

• Journal of Korean Academy of Nursing
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• v.46 no.1
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• pp.109-117
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• 2016

Purpose: The aim of this study was to develop a Korean version of Night Eating Questionnaire (KNEQ) and test its psychometric properties and evaluate items according to item response theory. Methods: The 14-item NEQ as a measure of severity of the night eating syndrome was translated into Korean, and then this KNEQ was evaluated. A total of 1171 participants aged 20 to 50 completed the KNEQ on the Internet. To test reliability and validity, Cronbach's alpha, correlation, simple regression, and factor analysis were used. Each item was analyzed according to Rasch-Andrich rating scale model and item difficulty, discrimination, infit/outfit, and point measure correlation were evaluated. Results: Construct validity was evident. Cronbach's alpha was .78. The items of evening hyperphagia and nocturnal ingestion showed high ability in discriminating people with night eating syndrome, while items of morning anorexia and mood/sleep provided relatively little information. The results of item analysis showed that item2 and item7 needed to be revised to improve the reliability of KNEQ. Conclusion: KNEQ is an appropriate instrument to measure severity of night eating syndrome with good validity and reliability. However, further studies are needed to find cut-off scores to screen persons with night eating syndrome.

• Physical Therapy Korea
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• v.11 no.2
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• pp.9-16
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• 2004

The purpose of this study was to validate the Korean version of the Gross Motor Function Measure (GMFM) using Rasch analysis. The data was obtained from the assessments of 59 children with cerebral palsy in Korea and were applied to Rasch's rating scale model to estimate the difficulty and goodness-of-fit of each item. Rasch modeling helped us to identify 76 items from the original 88-item GMFM that form an unidimensional hierarchical scale to rearrange 76 items in order of difficulty. Reliability coefficients of the 88-item and 76-item GMFM were .99 and .99, respectively. In this preliminary report, the Korean version of GMFM seems to have significant validity and reliability. These results may be useful in assessment of gross motor functions in children with cerebral palsy.

• The Journal of Korean Physical Therapy
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• v.30 no.6
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• pp.246-255
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• 2018

Purpose: This study was to conduct a Korean cultural adaptation of the WHO disability assessment schedule (WHODAS) 2.0: 36-item version. Methods: An internationally standardized process of translation and cultural adaptation of an instrument was used to develop a Korean version of WHODAS 2.0: 36-item version. Linking each item into the International Classification of Functioning, Disability and Health (ICF) was also conducted in order to ensure the concepts in the translated instrument were compatible with ICF. All translated versions of the instrument, linking results and feedback from participants were used for the final adaptation of the Korean version of the instrument. The Korean version of the instrument was assessed twice on different occasions to examine Inter- and intra-rater reliability, and the intra-class correlation coefficient (ICC) was calculated. Results: Twelve participants were involved in the translation and linking process. Ninety-five volunteers were invited to participate to examine the reliability of the instrument. Fifty participants completed the self-rated version of the instrument and 45 finished the interviewer version. The Korean WHODAS 2.0: 36-item version was found to have excellent reliability: self-rated version and interviewer version reliability coefficients were ICC=0.92 and ICC=0.94, respectively. Thirty-four items of the translated instrument were to be linked to ICF categories. Some adaptation was made; details and a familiar example were added to help respondents answer the questions. Conclusion: The study results show that the adaptation of the 36-item version of WHODAS 2.0 to Korean was successful and the instrument is ready for use in testing its psychometric properties.