1.Comparison of foodservice management performance level between dietitians and non-dietitians in senior centers using IPA.
Yun Kyoung LEE ; Ji Young YOON
Nutrition Research and Practice 2009;3(1):49-55
This study investigated the management importance and performance level of foodservice managers at senior centers. Using the survey, perceived importance and performance levels of seven foodservice management areas were evaluated and analyzed. Data showed the foodservice facilities were being managed by dietitians (61.6%) or non-dietitians (38.9%). The result indicated that overall importance level (3.43) was higher than performance level (3.02) (p<.01). As of the IPA result, dietitians and non-dietitians had different perspectives in terms of managing the eight categories of foodservice areas. The differences in the IPA results between the two groups may reflect bias attributable to the respondents' degrees of knowledge and professional preparation. The research findings could enhance our understanding of importance of hiring professional dietitians to operate foodservice at senior centers and find out which management area should be concentrated for more effective foodservice management.
Bias (Epidemiology)
2.Comparison of Control Methods for Estimation Bias in Unmatched Analysis of Matched Data.
Korean Journal of Preventive Medicine 1990;23(3):247-254
No abstract available.
Bias (Epidemiology)*
3.Bias related to Nutritional Epidemiology.
Korean Journal of Epidemiology 2003;25(1):39-46
Bias is the main problem that should be considered in epidemiologic research. Information bias caused by measurement error and confounding caused by total energy intake are listed as the main biases in nutritional epidemiology and the concept, fact and the methods for adjusting effects of these biases are discussed. The biases which can be caused during the nutritional epidemiologic research process are listed and discussed. The pros and cons of the continuous data and categorical data of the nutrients and the ways how to categorize the data are reviewed. During the analysis of food and nutrient data, multiple comparison and publication bias are prone to be encountered, and these should be considered in interpretation of the results. Understanding of the biases will lead us to make valuable nutritional epidemiologic research and these lead the application of the research results to control the prevalent noncommunicable diseases.
Bias (Epidemiology)*
;
Energy Intake
;
Epidemiology*
;
Publication Bias
4.The prevention and handling of the missing data.
Korean Journal of Anesthesiology 2013;64(5):402-406
Even in a well-designed and controlled study, missing data occurs in almost all research. Missing data can reduce the statistical power of a study and can produce biased estimates, leading to invalid conclusions. This manuscript reviews the problems and types of missing data, along with the techniques for handling missing data. The mechanisms by which missing data occurs are illustrated, and the methods for handling the missing data are discussed. The paper concludes with recommendations for the handling of missing data.
Bias (Epidemiology)
;
Handling (Psychology)
5.Development Of A Checklist For Assessing The Methodological And Statistical Validity Of Medical Articles.
Korean Journal of Medical Education 1991;3(1):19-35
It is necessary for medical readers or reviewers to assess critically the methodological and statistical validity of medical articles before accepting their results or conclusion. The authors develope d a validity-assessing checklist of 21 items. Among them 14 items for methodological validity included the followings : clear statement of research hypothesis or specific aims, suitable focus, definition of study population (or subjects), eligibility criteria, exclusion criteria, appropriateness of samples, description of methods in detail, desconclusion of accuracy, description of reliability, presence of control, susceptability bias, performance bias, detection bias, transfer bias. The last 5 items are applicable only to analytic study. And 7 errors to statistical validity : incomplete description of basic data, statistical test performed yet not defined, incomplete description of power or confidence interval, inadequate description of measures of central tendency or dispersion, incorrect analysis, multiplicity on hypothesis testing, unwarranted conclusion. The first 3 items are 'errors of omission', and the other are 'errors of commission'. The authors suggest the checklist be very helpful, but not perfect. Critical mind is needed, which enables someone to distinguish minor errors from major fallacies.
Bias (Epidemiology)
;
Checklist*
6.Relationship between Personality Type, SAT score and GPA of Student Nurses.
Ji Young LIM ; Il Young YOO ; Soon Nahm OH
Journal of Korean Academy of Nursing 2001;31(5):835-845
PURPOSE: This study was to identify the relationship between personality type, college admission SAT scores and GPA scores of student nurses. METHOD: The data was collected from 270 student nurses enrolled in a baccaleaureate program in Seoul. MBTI was used to identify students' personality and SAT score and GPA score were collected over 4 years. The collected data was analyzed by using SPSS Win. package. RESULT: 1. There were slightly more extrovert (E) type (54.4%) students than the introvert (I) type; more sensing (S) type (71.1%) than the intuitive (N) type. 2. The introvert type students had significantly higher SAT scores than those of the extrovert type (p=.002). 3. The judging type students had significantly higher GPA scores throughout their college years than the perceiving type. 4. There was no statistically significant relationship between SAT and GPA scores. SAT scores did not accurately predict students' academic achievement in college in this sample. CONCLUSION: The distribution of the personality types in the sample was different from the general population which may suggest that college admission criteria is biased toward certain personality type. Since different personality types process information and cope with the outside world differently, effective teaching strategies need to be considered for each class.
Bias (Epidemiology)
;
Humans
;
Seoul
7.Evaluation of HbA1c on COBAS INTEGRA 800 Closed Tube System Compared with Variant II Turbo.
EunYoung LEE ; Seoyoung YOON ; Sun Hee KIM ; Woonhyoung LEE ; Oh Hun KWON
Journal of Laboratory Medicine and Quality Assurance 2010;32(2):225-228
BACKGROUND: We evaluated the HbA1c assay on COBAS INTEGRA 800 Closed Tube System (Roche Diagnostics, USA). METHODS: Precision was determined following Clinical and Laboratory Standards Institute (CLSI) EP5-A2 using the Lyphochek Diabetes Control (Bio-Rad Laboratories, Canada). Two levels of QC materials were assayed in duplicates at two separate times per day for 20 days. The within-run, between-run and between-day precisions were evaluated. We compared the HbA1c of COBAS INTEGRA 800 Closed tube system using Tina quant Hemoglobin A1c Gen.2 (Roche Diagnostics, Germany) reagent with Variant II Turbo (Bio-Rad Laboratories, USA). Bias was determined following CLSI EP9-A2. RESULT: The HbA1c assay on COBAS INTEGRA 800 Closed Tube System showed excellent precision performance: at a level of 5.9%, total, between run, and between day CVs were 1.8%, 0.5%, and 1.6%, respectively. At a level of 9.6%, total, between run, and between day CVs were 1.4%, 0.3%, and 1.1%, respectively. The assay correlated well with the Variant II Turbo (y=0.9x+0.53, r2=0.9857). Mean bias against Variant II Turbo was -0.2%. Compared with Variant II Turbo, the estimate of the predicted bias at a given medical decision level (HbA1c at 6% and 9%) was -0.1% and -0.31%, respectively. CONCLUSIONS: The COBAS INTEGRA 800 Closed Tube System HbA1C assay was precise and equivalent to Variant II Turbo.
Bias (Epidemiology)
;
Hemoglobins
8.Assessment of risk of bias in quasi-randomized controlled trials and randomized controlled trials reported in the Korean Journal of Anesthesiology between 2010 and 2016.
Jong Hae KIM ; Tae Kyun KIM ; Junyong IN ; Dong Kyu LEE ; Sangseok LEE ; Hyun KANG
Korean Journal of Anesthesiology 2017;70(5):511-519
Bias affects the true intervention effect in randomized controlled trials (RCTs), making the results unreliable. We evaluated the risk of bias (ROB) of quasi-RCTs or RCTs reported in the Korean Journal of Anesthesiology (KJA) between 2010 and 2016. Six kinds of bias (selection, performance, detection, attrition, reporting, and other biases) were evaluated by determining low, unclear, or high ROB for eight domains (random sequence generation, allocation concealment, blinding of participants, blinding of personnel, blinding of outcome assessment, incomplete outcome data, selective reporting, and other bias) according to publication year. We identified 296 quasi-RCTs or RCTs. Random sequence generation was performed better than allocation concealment (51.7% vs. 20.9% for the proportion of low ROB, P < 0.001 and P = 0.943 for trend, respectively). Blinding of outcome assessment was superior to blinding of participants and personnel (42.9% vs. 15.5% and 23.0% for the proportion of low ROB, P = 0.026 vs. P = 0.003 and 0.896 for trend, respectively). Handling of incomplete outcome data was performed best with the highest proportion of low ROB (84.8%). Selective reporting had the lowest proportion of low ROB (4.7%). However, the ROB improved year by year (P < 0.001 for trend). Authors and reviewers should consider allocation concealment after random sequence generation, blinding of participants and personnel, and full reporting of results to improve the quality of RCTs submitted hereafter for publication in the KJA.
Anesthesiology*
;
Bias (Epidemiology)*
;
Publications
9.Comparison of Olfactory Threshold Tests:CCCRC Test versus Step Method.
Kyung Hun YANG ; Ic Tae KIM ; Young Min PARK
Korean Journal of Otolaryngology - Head and Neck Surgery 1997;40(3):389-396
There are many variables that can be manipulated in the study of olfactory thresholds. They include the choice of odorant, the way to bring the stimulus to the subject's nose, number of trials, interval between trials, dilution method, environmental conditions, as well as psychophysical method. The focus of this study lay on how much differences were made by the psychophysical method, the sequence of presentations of stimuli that led to calculation of an index of sensitivity and how reliable the result of step method in olfactory threshold testing is. The olfactory threshold tests entailed comparison of procedures: 1) a procedure of two-alternative forced-choice(2AFC) testing by an ascending method of limits(CCCRC test), 2) a two-alternative forced-choice(2AFC) version of step method that used a computerized algorithm to calculate threshold on an ongoing basis throughout testing. As a result, mean concentration difference of 7.6-fold was achieved in the thresholds by the two procedures and inter-test correlation coefficient was 0.46. Estimation of threshold in the step method remained relatively constant after 10 trials to the end of the 30 test-trials without biases, which meant step method showed coherent data. Accordingly step method is suitable for olfactory threshold test despite of relatively long testing time.
Bias (Epidemiology)
;
Nose
;
Odors
10.Introduction to systematic review and meta-analysis.
Korean Journal of Anesthesiology 2018;71(2):103-112
Systematic reviews and meta-analyses present results by combining and analyzing data from different studies conducted on similar research topics. In recent years, systematic reviews and meta-analyses have been actively performed in various fields including anesthesiology. These research methods are powerful tools that can overcome the difficulties in performing large-scale randomized controlled trials. However, the inclusion of studies with any biases or improperly assessed quality of evidence in systematic reviews and meta-analyses could yield misleading results. Therefore, various guidelines have been suggested for conducting systematic reviews and meta-analyses to help standardize them and improve their quality. Nonetheless, accepting the conclusions of many studies without understanding the meta-analysis can be dangerous. Therefore, this article provides an easy introduction to clinicians on performing and understanding meta-analyses.
Anesthesiology
;
Bias (Epidemiology)