Purpose: Immunochemical fecal occult blood tests (iFOBT) have been utilized as the primary method for colorectal cancer screening within Korea's National Cancer Screening Program. This study aimed to evaluate the impact of the accreditation program for clinical laboratories and external quality assessment (EQA) programs on colorectal cancer screening. Methods: We analyzed the false-positive rates of iFOBT in colorectal cancer screening from 2016 to 2020 according to participation and performance in the Outstanding Laboratory Accreditation Program (OLAP) conducted by the Laboratory Medicine Foundation, and the External Quality Assessment programs run by the Korean Association of External Quality Assessment Service. Results: False-positive rates of iFOBT were lower among institutions accredited by OLAP (2.35%) compared with non-accredited (3.04%) and non-participating institutions (5.60%). Similarly, institutions participating in the EQA program exhibited lower false-positive rates (3.79%) compared to non-participants (7.04%). Within the iFOBT-specific EQA program, institutions that passed demonstrated the lowest false-positive rate (3.37%), while failing institutions showed the highest rate (9.07%), surpassing even non-participating institutions (6.44%). Conclusion Participation in quality management programs such as OLAP and EQA was associated with lower false-positive rates in iFOBT for colorectal cancer screening. These findings suggest that quality management initiatives can increase the accuracy of iFOBT, potentially improving the effectiveness of colorectal cancer screening programs, and reducing unnecessary follow-up procedures and associated healthcare costs.

Purpose: Immunochemical fecal occult blood tests (iFOBT) have been utilized as the primary method for colorectal cancer screening within Korea's National Cancer Screening Program. This study aimed to evaluate the impact of the accreditation program for clinical laboratories and external quality assessment (EQA) programs on colorectal cancer screening. Methods: We analyzed the false-positive rates of iFOBT in colorectal cancer screening from 2016 to 2020 according to participation and performance in the Outstanding Laboratory Accreditation Program (OLAP) conducted by the Laboratory Medicine Foundation, and the External Quality Assessment programs run by the Korean Association of External Quality Assessment Service. Results: False-positive rates of iFOBT were lower among institutions accredited by OLAP (2.35%) compared with non-accredited (3.04%) and non-participating institutions (5.60%). Similarly, institutions participating in the EQA program exhibited lower false-positive rates (3.79%) compared to non-participants (7.04%). Within the iFOBT-specific EQA program, institutions that passed demonstrated the lowest false-positive rate (3.37%), while failing institutions showed the highest rate (9.07%), surpassing even non-participating institutions (6.44%). Conclusion Participation in quality management programs such as OLAP and EQA was associated with lower false-positive rates in iFOBT for colorectal cancer screening. These findings suggest that quality management initiatives can increase the accuracy of iFOBT, potentially improving the effectiveness of colorectal cancer screening programs, and reducing unnecessary follow-up procedures and associated healthcare costs.

Purpose: Immunochemical fecal occult blood tests (iFOBT) have been utilized as the primary method for colorectal cancer screening within Korea's National Cancer Screening Program. This study aimed to evaluate the impact of the accreditation program for clinical laboratories and external quality assessment (EQA) programs on colorectal cancer screening. Methods: We analyzed the false-positive rates of iFOBT in colorectal cancer screening from 2016 to 2020 according to participation and performance in the Outstanding Laboratory Accreditation Program (OLAP) conducted by the Laboratory Medicine Foundation, and the External Quality Assessment programs run by the Korean Association of External Quality Assessment Service. Results: False-positive rates of iFOBT were lower among institutions accredited by OLAP (2.35%) compared with non-accredited (3.04%) and non-participating institutions (5.60%). Similarly, institutions participating in the EQA program exhibited lower false-positive rates (3.79%) compared to non-participants (7.04%). Within the iFOBT-specific EQA program, institutions that passed demonstrated the lowest false-positive rate (3.37%), while failing institutions showed the highest rate (9.07%), surpassing even non-participating institutions (6.44%). Conclusion Participation in quality management programs such as OLAP and EQA was associated with lower false-positive rates in iFOBT for colorectal cancer screening. These findings suggest that quality management initiatives can increase the accuracy of iFOBT, potentially improving the effectiveness of colorectal cancer screening programs, and reducing unnecessary follow-up procedures and associated healthcare costs.

Background and Objectives: Recent guidelines from the Korean Thyroid Association have proposed a threshold of 6.8 mIU/L for diagnosing subclinical hypothyroidism based on local research findings. However, due to the lack of standardization/harmonization, thyroid-stimulating hormone (TSH) testing yields varying results across different reagent manufacturers. Hence, the use of uniform reference intervals is challenging. We aimed to establish assay-specific Korean reference interval for TSH. Materials and Methods: We performed duplicate measurements on 100 serum samples with varying TSH concentrations (0-23 mIU/L) using eight different TSH reagents including Alinity I TSH (Abbott), Access TSH (Beckman Coulter), Elecsys TSH (Roche), TSH3UL (Siemens),TSH IRMA (Beckman Coulter), TSH1 RIA (Brahms), TSH IRMA TUBE II (Riakey), Turbo TSH IRMA (Izotop).Correlation and simple linear regression analyses were conducted among 8 reagents with Roche as the reference. Results The correlation coefficient for each reagent was notably high at 0.99. Through regression analysis, TSH values equivalent to the 6.8 mIU/L (Roche) were determined for each reagent as follows: Abbott 5.2 mIU/L, Beckman 6.5 mIU/L, Siemens 6.9 mIU/L, Beckman-Radioimmunoassay 7.4 mIU/L, Brahms 5.7 mIU/L, Riakey 5.3 mIU/L, Izotop 6.0 mIU/L. Conclusion: Given the observed differences in TSH values associated with different reagents, it is imperative to consider these differences when interpreting results within various clinical contexts and adapting them to clinical practice.

Objectives: The purpose of this study is to analyze the relationship between dental school students’admission scores and their grade point average (GPA) after admission, as well as the relationship between student admission scores at dental school and continuation into the residency program. Methods: This study analyzed data collected from students who entered dental school between 2013 and 2017. The outcome variables were dental school GPA and continuation into residency program. Explanatory variables included admission type (early decision admission/regular admission), academic achievements (undergraduate GPA, Dental Education Eligibility Test [DEET], Test of English Proficiency [TEPS], screening by document review, and in-depth interview score), age, sex, college alma mater, high school alma mater, college major, as well as students’ academic performance in dental school. Regression analysis was performed to determine which factors relating to dental school admissions score had an influence on academic performance in dental school, whereas logistic regression analysis was conducted to determine the students’ decision to pursue a residency. Results: Students who were foreign college graduates, majored in health sciences, accepted on the basis of early decision admission, female, or had a higher college GPA showed higher dental school GPA with statistical significance. Additionally, the likelihood of students pursuing residency was found to be higher in students who were female, of younger age, college graduates in Jeolla Provinces, or who had a higher dental school GPA. Conclusions To ensure regional equality of dental service quality, it is essential that high quality students pursue residency training. For further improvement of dental school, this study’s results can be used as a reference to make students coming from other regions pursue the residency program and contribute to the regional community.

BACKGROUND: The gold standard in dysarthria assessment involves subjective analysis by a speech–language pathologist (SLP). We aimed to investigate the feasibility of dysarthria assessment using automatic speech recognition. METHODS: We developed an automatic speech recognition based software to assess dysarthria severity using hidden Markov models (HMMs). Word-specific HMMs were trained using the utterances from one hundred healthy individuals. Twenty-eight patients with dysarthria caused by neurological disorders, including stroke, traumatic brain injury, and Parkinson's disease were participated and their utterances were recorded. The utterances of 37 words from the Assessment of Phonology and Articulation for Children test were recorded in a quiet control booth in both groups. Patients were asked to repeat the recordings for evaluating the test–retest reliability. Patients' utterances were evaluated by two experienced SLPs, and the consonant production accuracy was calculated as a measure of dysarthria severity. The trained HMMs were also employed to evaluate the patients' utterances by calculating the averaged log likelihood (aLL) as the fitness of the spoken word to the word-specific HMM. RESULTS: The consonant production accuracy reported by the SLPs strongly correlated (r = 0.808) with the aLL, and the aLL showed excellent test–retest reliability (intraclass correlation coefficient, 0.964). CONCLUSION: This leads to the conclusion that dysarthria assessment using a one-word speech recognition system based on word-specific HMMs is feasible in neurological disorders.
Brain Injuries ; Child ; Dysarthria ; Humans ; Nervous System Diseases ; Parkinson Disease ; Stroke

As dried blood spots (DBSs) have various advantages over conventional venous blood sampling, some assays for detection of one or two anti-tuberculosis (TB) drugs in DBSs have been developed. However, there are no assays currently available for the simultaneous measurement of three or more anti-TB drugs in DBSs. In this study, we developed and evaluated a multiplex method for detecting nine anti-TB drugs including streptomycin, kanamycin, clarithromycin, cycloserine, moxifloxacin, levofloxacin, para-aminosalicylic acid, prothionamide, and linezolid in DBSs by using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Seventy-nine patient samples of DBS were analyzed on the UPLC-MS/MS system. All drug concentrations were determined within 4 min, and assay performance was evaluated. All drugs were clearly separated without ion suppression. Within-run and between-run precisions were 1.7-13.0% and 5.7-17.0%, respectively, at concentrations representing low and high levels for the nine drugs. Lower limits of detection and quantification were 0.06-0.6 and 0.5-5.0 µg/mL, respectively. Linearity was acceptable at five level concentrations for each drug. Correlations between drug concentrations in plasma and DBSs by using Passing-Bablock regression and Pearson's rho (ρ, 0.798-0.989) were acceptable. In conclusion, we developed a multiplex assay to measure nine second-line anti-TB drugs in DBSs successfully. This assay provided convenient and rapid drug quantification and could have applications in drug monitoring during treatment.
Antitubercular Agents/*blood ; Chromatography, High Pressure Liquid ; *Dried Blood Spot Testing ; Humans ; Limit of Detection ; Reproducibility of Results ; *Tandem Mass Spectrometry

OBJECTIVES: Cyberbullying has recently become a major concern in Korea and especially poses a serious threat to adolescents. The object of this study is to examine the psychopathology of perpetrators and victims of cyberbullying. METHODS: In a cross-sectional study, 490 middle school students completed questionnaires on bullying and victimization experiences in cyberspace. Korean-Youth Self Report (K-YSR) was included to evaluate the psychopathology of the students. RESULTS: The prevalence rates of victims and perpetrators of cyberbullying were 6.92% and 3.33%, respectively. Among 9 sub-scales of K-YSR, the scores of depressed/anxious (p=0.049), thought problems (p=0.002), and attention problems (p=0.039) were significantly different between victim, perpetrator, victim/perpetrator, and control group. Multinomial logistic regression indicated that the victim group was associated with depressed/anxious [odds ratio (OR)=1.10], social immaturity (OR=1.24), thought problems (OR=1.32), and self-destructive identity problems (OR=1.16). The perpetrator group was associated with thought problems (OR=1.37) and attention problems (OR=1.21). The victim/perpetrator group was associated with delinquent behavior (OR=2.04). CONCLUSION: Middle school students involved in cyberbullying were associated with psychopathologies including depression, anxiety, thought problems, attention problems, and delinquent behaviors. The risk of cyberbullying is escalating with the rapid advancement in technology. Therefore, a comprehensive approach should be employed for prediction and prevention of cyberbullying in adolescents.
Adolescent ; Anxiety ; Bullying* ; Crime Victims ; Cross-Sectional Studies ; Depression ; Humans ; Korea ; Logistic Models ; Prevalence ; Psychopathology* ; Surveys and Questionnaires ; Self Report

Metachromatic leukodystrophy (MLD) is an autosomal recessive disease caused by a deficiency in arylsulfatase A (ARSA). However, decreased ARSA activity is also observed in pseudodeficiency (PD). To distinguish between MLD and PD, we performed gene mutation and sulfatide analyses by using dried blood spots (DBSs) from seven Korean individuals who underwent an analysis of ARSA activity. DNA was extracted from DBSs, and PCR-direct sequencing of ARSA was performed. The cDNA obtained was analyzed to confirm a novel mutation. Of the seven subjects, three were confirmed as having MLD, one was confirmed as having MLD-PD, one was confirmed as having PD, and the remaining two were obligate heterozygotes. We verified the novel pathogenic variant c.1107+1delG by performing familial and cDNA analyses. Sulfatide concentrations in DBSs were analyzed and were quantified by using ultra-performance liquid chromatography and tandem mass spectrometry, respectively. Total sulfatide concentration was inversely correlated with ARSA activity (Spearman's coefficient of rank correlation, P=0.929, P=0.0025). The results of this mutational and biochemical study on MLD will increase our understanding of the genetic characteristics of MLD in Koreans.
Cerebroside-Sulfatase ; Chromatography, Liquid ; DNA ; DNA, Complementary ; Heterozygote ; Leukodystrophy, Metachromatic* ; Tandem Mass Spectrometry

BACKGROUND: Busulfan, an alkylating agent administered prior to hematopoietic stem cell transplantation, has a narrow therapeutic range and wide variability in metabolism. We developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for rapid and accurate quantification of plasma busulfan. METHODS: Busulfan was separated and detected using an LC system containing a C18 column equipped with MS/MS. The sample was eluted with a mobile phase gradient for a total run time of 10 min. Plasma busulfan concentration was quantified against a 6-point standard curve in a multiple reaction monitoring mode at mass-to-charge (m/z) 264.1 > 151.1. Precision, recovery, matrix effect, linearity, detection capability, carryover, and stability were evaluated. The range of plasma busulfan concentration was obtained by analyzing samples from 9 children receiving busulfan. RESULTS: The coefficients of variation of within-run and within-laboratory precision were all below 5%. Recoveries were all within the range of 100-105%. Linearity was verified from 0 to 5,000 ng/mL. Limit of detection and limit of quantification were 1.56 and 25 ng/mL, respectively. Carryover rate was within allowable limits. Plasma busulfan concentration was stable for 2 weeks at -20degrees C and -80degrees C, but decreased by 25% when the plasma was stored for 24 hr at room temperature, and by <5% in 24 hr at 4degrees C. The plasma busulfan concentrations were between 347 ng/mL and 5,076 ng/mL. CONCLUSIONS: Our method using LC-MS/MS enables highly accurate, reproducible, and rapid busulfan monitoring with minimal sample preparation. The method may also enable safe and proper dosage.
Busulfan/*blood/standards ; Child ; Child, Preschool ; *Chromatography, High Pressure Liquid/standards ; Hematopoietic Stem Cell Transplantation ; Humans ; Infant ; Quality Control ; Reference Standards ; *Tandem Mass Spectrometry/standards