1.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
2.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
3.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
4.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
5.Early Prediction of Mortality for Septic Patients Visiting Emergency Room Based on Explainable Machine Learning: A Real-World Multicenter Study
Sang Won PARK ; Na Young YEO ; Seonguk KANG ; Taejun HA ; Tae-Hoon KIM ; DooHee LEE ; Dowon KIM ; Seheon CHOI ; Minkyu KIM ; DongHoon LEE ; DoHyeon KIM ; Woo Jin KIM ; Seung-Joon LEE ; Yeon-Jeong HEO ; Da Hye MOON ; Seon-Sook HAN ; Yoon KIM ; Hyun-Soo CHOI ; Dong Kyu OH ; Su Yeon LEE ; MiHyeon PARK ; Chae-Man LIM ; Jeongwon HEO ; On behalf of the Korean Sepsis Alliance (KSA) Investigators
Journal of Korean Medical Science 2024;39(5):e53-
Background:
Worldwide, sepsis is the leading cause of death in hospitals. If mortality rates in patients with sepsis can be predicted early, medical resources can be allocated efficiently. We constructed machine learning (ML) models to predict the mortality of patients with sepsis in a hospital emergency department.
Methods:
This study prospectively collected nationwide data from an ongoing multicenter cohort of patients with sepsis identified in the emergency department. Patients were enrolled from 19 hospitals between September 2019 and December 2020. For acquired data from 3,657 survivors and 1,455 deaths, six ML models (logistic regression, support vector machine, random forest, extreme gradient boosting [XGBoost], light gradient boosting machine, and categorical boosting [CatBoost]) were constructed using fivefold cross-validation to predict mortality. Through these models, 44 clinical variables measured on the day of admission were compared with six sequential organ failure assessment (SOFA) components (PaO 2 /FIO 2 [PF], platelets (PLT), bilirubin, cardiovascular, Glasgow Coma Scale score, and creatinine).The confidence interval (CI) was obtained by performing 10,000 repeated measurements via random sampling of the test dataset. All results were explained and interpreted using Shapley’s additive explanations (SHAP).
Results:
Of the 5,112 participants, CatBoost exhibited the highest area under the curve (AUC) of 0.800 (95% CI, 0.756–0.840) using clinical variables. Using the SOFA components for the same patient, XGBoost exhibited the highest AUC of 0.678 (95% CI, 0.626–0.730). As interpreted by SHAP, albumin, lactate, blood urea nitrogen, and international normalization ratio were determined to significantly affect the results. Additionally, PF and PLTs in the SOFA component significantly influenced the prediction results.
Conclusion
Newly established ML-based models achieved good prediction of mortality in patients with sepsis. Using several clinical variables acquired at the baseline can provide more accurate results for early predictions than using SOFA components. Additionally, the impact of each variable was identified.
6.Impact of Adjuvant Hormone Therapy on Sleep, Physical Activity, and Quality of Life in Premenopausal Breast Cancer: 12-Month Observational Study
Seung Mi YEO ; Ji Young LIM ; Seok Won KIM ; Byung Joo CHAE ; Jonghan YU ; Jai Min RYU ; Ji Hye HWANG
Journal of Breast Cancer 2023;26(2):93-104
Purpose:
This study aimed to investigate the differences in sleep disturbance changes between patients receiving two hormone therapies (“tamoxifen plus ovarian function suppression group [T+OFS group]” versus “tamoxifen group [T group]”) and the chronological changes in sleep disturbances in each group.
Methods:
Premenopausal women with unilateral breast cancer who underwent surgery and were scheduled to receive hormone therapy (HT) with tamoxifen alone or with tamoxifen plus gonadotropin-releasing hormone (GnRH) agonist for ovarian function suppression were included. The enrolled patients wore an actigraphy watch for two weeks and completed questionnaires (insomnia, sleep quality, physical activity [PA], and quality of life [QOL]) at five time points: immediately before HT and 2, 5, 8, and 11 months after HT.
Results:
Among the 39 enrolled patients (21 and 18 patients in the T+OFS group and T group, respectively), 25 (17 and 8 patients in the T+OFS group and T group, respectively) were finally analyzed. There were no differences between the two groups in time-dependent changes in insomnia, sleep quality, total sleep time, rapid eye movement sleep rate, QOL, and PA;however, the severity of hot flashes was significantly higher in the T+OFS group than in the T group. Although the interaction between group and time was not significant, insomnia and sleep quality significantly worsened at 2–5 months of HT when changes over time were analyzed within the T+OFS group. In both the groups, PA and QOL were maintained without significant changes.
Conclusion
Unlike tamoxifen alone, tamoxifen plus GnRH agonist initially worsened insomnia and sleep quality, but gradually improved with long-term follow-up. Patients who initially experience insomnia during tamoxifen plus GnRH agonist administration can be reassured based on the results of this study, and active supportive care may be used during this period.
7.Clinical Characteristics of Intermittent Esotropia
Young Chae YOON ; Nam Yeo KANG
Journal of the Korean Ophthalmological Society 2021;62(12):1650-1656
Purpose:
To evaluate clinical findings and surgical outcomes of intermittent esotropia.
Methods:
We retrospectively reviewed the medical records of 23 patients (aged 9-42 years) who presented with intermittent esotropia between January 2007 and December 2020. We analyzed the age at onset, angle of deviation, presence of symptomatic diplopia, fusional state, near stereoacuity, and surgical results.
Results:
The mean age at onset was 19.9 ± 8.0 years and mean duration of esodeviation was 23.4 ± 27.1 months. Mean follow-up time was 13.0 ± 15.6 months. All patients except three had symptomatic diplopia, and 78.3% showed intermittent diplopia. Mean angles of deviation were 21.6 ± 10.3 prism diopters (PD) at distance and 20.2 ± 10.4 PD at near. Twenty-one patients (91.3%) were myopia. No patients had amblyopia and one had dissociated vertical deviation. On Worth’s four-dot test, five patients (21.7%) showed diplopia and four showed suppression at both distance and near. The other patients showed fusion at near or distance. Eleven patients underwent surgical correction. At the final examination, all patients achieved successful motor alignment and fusion with resolution of diplopia. Only two patients (18.2%) achieved normal 60 arcsec stereopsis, and six attained subnormal stereopsis.
Conclusions
The main symptom of intermittent esotropia was diplopia. Surgical treatment was effective in achieving good postoperative motor alignment and fusion. However, successful motor alignment did not guarantee recovery of fine stereopsis.
8.Protective efficacy of attenuated Salmonella Typhimurium strain expressing BLS, Omp19, PrpA, or SOD of Brucella abortus in goats
Mwense LEYA ; Won Kyong KIM ; Enkhsaikhan OCHIRKHUYAG ; Eun-Chae YU ; Young-Jee KIM ; Yoonhwan YEO ; Myeon-Sik YANG ; Sang-Seop HAN ; John Hwa LEE ; Dongseob TARK ; Jin HUR ; Bumseok KIM
Journal of Veterinary Science 2021;22(2):e15-
Background:
Attenuated Salmonella strain can be used as a vector to transport immunogens to the host antigen-binding sites.
Objectives:
The study aimed to determine the protective efficacy of attenuated Salmonellastrain expressing highly conserved Brucella immunogens in goats.
Methods:
Goats were vaccinated with Salmonella vector expressing individually lipoprotein outer-membrane protein 19 (Omp19), Brucella lumazine synthase (BLS), proline racemase subunit A (PrpA), Cu/Zn superoxide dismutase (SOD) at 5 × 10 9 CFU/mL and challenge of all groups was done at 6 weeks after vaccination.
Results:
Among these vaccines inoculated at 5 × 10 9 CFU/mL in 1 mL, Omp19 or SOD showed significantly higher serum immunoglobulin G titers at (2, 4, and 6) weeks post-vaccination, compared to the vector control. Interferon-γ production in response to individual antigens was significantly higher in SOD, Omp19, PrpA, and BLS individual groups, compared to that in the vector control (all p < 0.05). Brucella colonization rate at 8 weeks post-challenge showed that most vaccine-treated groups exhibited significantly increased protection by demonstrating reduced numbers of Brucella in tissues collected from vaccinated groups. Realtime polymerase chain reaction revealed that Brucella antigen expression levels were reduced in the spleen, kidney, and parotid lymph node of vaccinated goats, compared to the nonvaccinated goats. Besides, treatment with vaccine expressing individual antigens ameliorated brucellosis-related histopathological lesions.
Conclusions
These results delineated that BLS, Omp19, PrpA, and SOD proteins achieved a definite level of protection, indicating that Salmonella Typhimurium successfully delivered Brucella antigens, and that individual vaccines could differentially elicit an antigen-specific immune response.
9.Protective efficacy of attenuated Salmonella Typhimurium strain expressing BLS, Omp19, PrpA, or SOD of Brucella abortus in goats
Mwense LEYA ; Won Kyong KIM ; Enkhsaikhan OCHIRKHUYAG ; Eun-Chae YU ; Young-Jee KIM ; Yoonhwan YEO ; Myeon-Sik YANG ; Sang-Seop HAN ; John Hwa LEE ; Dongseob TARK ; Jin HUR ; Bumseok KIM
Journal of Veterinary Science 2021;22(2):e15-
Background:
Attenuated Salmonella strain can be used as a vector to transport immunogens to the host antigen-binding sites.
Objectives:
The study aimed to determine the protective efficacy of attenuated Salmonellastrain expressing highly conserved Brucella immunogens in goats.
Methods:
Goats were vaccinated with Salmonella vector expressing individually lipoprotein outer-membrane protein 19 (Omp19), Brucella lumazine synthase (BLS), proline racemase subunit A (PrpA), Cu/Zn superoxide dismutase (SOD) at 5 × 10 9 CFU/mL and challenge of all groups was done at 6 weeks after vaccination.
Results:
Among these vaccines inoculated at 5 × 10 9 CFU/mL in 1 mL, Omp19 or SOD showed significantly higher serum immunoglobulin G titers at (2, 4, and 6) weeks post-vaccination, compared to the vector control. Interferon-γ production in response to individual antigens was significantly higher in SOD, Omp19, PrpA, and BLS individual groups, compared to that in the vector control (all p < 0.05). Brucella colonization rate at 8 weeks post-challenge showed that most vaccine-treated groups exhibited significantly increased protection by demonstrating reduced numbers of Brucella in tissues collected from vaccinated groups. Realtime polymerase chain reaction revealed that Brucella antigen expression levels were reduced in the spleen, kidney, and parotid lymph node of vaccinated goats, compared to the nonvaccinated goats. Besides, treatment with vaccine expressing individual antigens ameliorated brucellosis-related histopathological lesions.
Conclusions
These results delineated that BLS, Omp19, PrpA, and SOD proteins achieved a definite level of protection, indicating that Salmonella Typhimurium successfully delivered Brucella antigens, and that individual vaccines could differentially elicit an antigen-specific immune response.
10.Panel-Reactive and Donor-Specific Antibodies before Lung Transplantation can Affect Outcomes in Korean Patients Receiving Lung Transplantation
Sung Woo MOON ; Moo Suk PARK ; Jin Gu LEE ; Hyo Chae PAIK ; Young Tae KIM ; Hyun Joo LEE ; Samina PARK ; Sun Mi CHOI ; Do Hyung KIM ; Woo Hyun CHO ; Hye Ju YEO ; Seung-il PARK ; Se Hoon CHOI ; Sang-Bum HONG ; Tae Sun SHIM ; Kyung-Wook JO ; Kyeongman JEON ; Byeong-Ho JEONG ; Song Yee KIM ;
Yonsei Medical Journal 2020;61(7):606-613
Purpose:
Data on the distribution and impact of panel reactive antibodies (PRA) and donor specific antibodies (DSA) before lung transplantation in Asia, especially multi-center-based data, are limited. This study evaluated the prevalence of and effects of PRA and DSA levels before lung transplantations on outcomes in Korean patients using nationwide multicenter registry data.
Materials and Methods:
This study included 103 patients who received a lung transplant at five tertiary hospitals in South Korea between March 2015 and December 2017. Mortality, primary graft dysfunction (PGD), and bronchiolitis obliterans syndrome (BOS) were evaluated.
Results:
Sixteen patients had class I and/or class II PRAs exceeding 50%. Ten patients (9.7%) had DSAs with a mean fluorescence intensity (MFI) higher than 1000, six of whom had antibodies with a high MFI (≥2000). DSAs with high MFIs were more frequently observed in patients with high-grade PGD (≥2) than in those with no or low-grade (≤1) PGD. In the 47 patients who survived for longer than 9 months and were evaluated for BOS after the transplant, BOS was not related to DSA or PRA levels. One-year mortality was more strongly related to PRA class I exceeding 50% than that under 50% (0% vs. 16.7%, p=0.007).
Conclusion
Preoperative DSAs and PRAs are related to worse outcomes after lung transplantation. DSAs and PRAs should be considered when selecting lung transplant recipients, and recipients who have preoperative DSAs with high MFI values and high PRA levels should be monitored closely after lung transplantation.

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