Exploring the genetic diversity of the Japanese population: Insights from a large-scale whole genome sequencing analysis.

The Japanese archipelago is a terminal location for human migration, and the contemporary Japanese people represent a unique population whose genomic diversity has been shaped by multiple migrations from Eurasia. We analyzed the genomic characteristics that define the genetic makeup of the modern Japanese population from a population genetics perspective from the genomic data of 9,287 samples obtained by high-coverage whole-genome sequencing (WGS) by the National Center Biobank Network. The dataset comprised populations from the Ryukyu Islands and other parts of the Japanese archipelago (Hondo). The Hondo population underwent two episodes of population decline during the Jomon period, corresponding to the Late Neolithic, and the Edo period, corresponding to the Early Modern era, while the Ryukyu population experienced a population decline during the shell midden period of the Late Neolithic in this region. Haplotype analysis suggested increased allele frequencies for genes related to alcohol and fatty acid metabolism, which were reported as loci that had experienced positive natural selection. Two genes related to alcohol metabolism were found to be 12,500 years out of phase with the time when they began to increase in the allele frequency; this finding indicates that the genomic diversity of Japanese people has been shaped by events closely related to agriculture and food production.

Development and Validation of Claims-based Algorithms for Identifying Hospitalized Patients With COVID-19 and Their Severity in 2020 and 2021.

BACKGROUND: This study aimed to develop and validate claims-based algorithms for identifying hospitalized patients with coronavirus disease 2019 (COVID-19) and disease severity. METHODS: We used claims data including all patients at the National Center for Global and Medicine Hospital between January 1, 2020, and December 31, 2021. The claims-based algorithms for three statuses with COVID-19 (hospitalizations, moderate or higher status, and severe status) were developed using diagnosis codes (International Classification of Diseases, 10th revision code: U07.1, B34.2) and relevant medical procedure code. True cases were determined using the COVID-19 inpatient registry and electronic health records. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each algorithm at 6-month intervals. RESULTS: Of the 75,711 total patients, the number of true cases was 1,192 for hospitalizations, 622 for moderate or higher status, and 55 for severe status. The diagnosis code-only algorithm for hospitalization had sensitivities 90.4% to 94.9% and PPVs 9.3% to 19.4%. Among the algorithms consisting of both diagnosis codes and procedure codes, high sensitivity and PPV were observed during the following periods: 93.9% and 97.1% for hospitalization (January-June 2021), 90.4% and 87.5% for moderate or higher status (July-December 2021), and 92.3% and 85.7% for severe status (July-December 2020), respectively. Almost all algorithms had specificities and NPVs of approximately 99%. CONCLUSION: The diagnosis code-only algorithm for COVID-19 hospitalization showed low validity throughout the study period. The algorithms for hospitalizations, moderate or higher status, and severe status with COVID-19, consisting of both diagnosis codes and procedure codes, showed high validity in some periods.

The association between experience of COVID-19-related discrimination and psychological distress among healthcare workers for six national medical research centers in Japan.

BACKGROUND: Discrimination is an important determinant of negative mental health outcomes. This study determined the association between the experience of COVID-19-related discrimination and psychological distress among healthcare workers (HCWs) in Japan. METHODS: This cross-sectional study conducted a health survey among 5703 HCWs of six national medical and research centers in Japan from October 2020 to March 2021. COVID-19-related discrimination was defined either when participants or their family members were badmouthed or when they felt discriminated against in some way. We used the Kessler Psychological Distress Scale (K6) to assess the presence of severe psychological distress (≥ 13 points). We used logistic regression models to examine the association between discrimination and psychological distress. We also identified factors associated with discrimination. RESULTS: Of the participants, 484 (8.4%) reported COVID-19-related discrimination and 486 (8.5%) had severe psychological distress. HCWs who were female vs. male (adjusted odds ratio [AOR] = 1.41, 95% confidence interval [CI] = 1.28-1.55), had high vs. low viral exposure (AOR = 2.31, 95% CI = 1.81-2.93), and worked for 11 or more hours/day vs. 8 or less hours/day (AOR = 1.42, 95% CI = 1.35-1.49) were more likely to have experienced COVID-19-related discrimination. The AOR (95% CI) of severe psychological distress was 1.83 (1.29-2.59) among those who experienced discrimination. In the stratified analysis by sociodemographic and job-related factors, all the interactions did not reach statistical significance (p for interaction > 0.20). CONCLUSION: Experience of COVID-19-related discrimination was associated with severe psychological distress among HCWs. During the pandemic, effective measures should be taken to prevent the development of negative mental health outcomes in HCWs who experience discrimination.

Use of heated tobacco products, moderate alcohol drinking, and anti-SARS-CoV-2 IgG antibody titers after BNT162b2 vaccination among Japanese healthcare workers.

The effect of heated tobacco products (HTPs) use and moderate alcohol drinking on immunogenicity to coronavirus disease (COVID-19) vaccines remain elusive. This study aimed to examine the association of tobacco product use and alcohol consumption with anti-SARS-CoV-2 spike IgG antibody titers after the BNT162b2 vaccine. Participants were 3433 healthcare workers receiving two vaccine doses in the 4 national centers for advanced medical and research in Japan. Smoking status and alcohol consumption were assessed via a questionnaire, and anti-SARS-CoV-2 spike IgG titers were measured with chemiluminescent enzyme immunoassay using serum collected on the median of 64 days after the second vaccination. Multilevel linear regression models were used to estimate the geometric mean titers (GMT) and the ratios of means (RoM) between groups with adjustment for covariates. Compared with never-smokers (GMT = 118), IgG antibody titers were significantly lower among HTPs users (including those who also smoked cigarettes) (GMT = 105; RoM = 0.89 [95%CI: 0.78-0.99]) and exclusive cigarettes smokers (GMT = 98; RoM = 0.81 [95%CI: 0.71-0.92]). Compared with non-drinkers of alcohol (GMT = 123), alcohol drinkers consuming <1 go/day (GMT = 113; RoM = 0.93 [95%CI: 0.88-0.98]), 1-1.9 go/day (GMT = 104; RoM = 0.85 [95%CI: 0.78-0.93]), and ≥ 2 go/day (GMT = 103; RoM = 0.84 [95%CI: 0.74-0.96]) had significantly lower antibody titers (P for trend<0.01). Spline analysis showed a large reduction of antibody until around 1 go/day of alcohol consumption, and then they gradually decreased. Results suggest that in addition to conventional cigarette smoking and heavy alcohol drinking, HTPs use and moderate alcohol drinking may be predictors of lower immunological response to COVID-19 vaccine.

Case-Reported Data Management Methodology Using an RDF Data Model for Building a Multicenter Clinical Registry.

In multicenter clinical research, case-reported clinical data are managed for each research project. Participating institutions manage the mapping between standardized codes and in-house codes. To use the data extracted from electronic medical records in case report forms, it is necessary to pay attention to the gap in the semantic hierarchy. Managing mapping information between in-house and standardized codes is centralized in Resource Description Framework (RDF) stores. The relationship between standardized and in-house codes is described in RDF and stored in RDF stores. RESTful APIs for accessing RDF stores in SPARQL was developed and verified. The relationship between standardized codes and in-house codes of pharmaceuticals was expressed in RDF triples. As a +result of the operational verification of the implemented APIs, it was confirmed that data management with knowledge bases expressed in RDF graphs is possible. The ability to dynamically modify mapping definitions enables flexible data management and ease of operational restrictions.

Improved Nursing Workload by Introducing a Traceability System to Manage Medical Materials.

This paper reports a case study in which an improvement in nursing work was achieved through the introduction of a traceability system compatible with radio-frequency identification (RFID) and bar codes for the management of medical materials. In verifying the RFID-based system in an operating room, the work time was reduced to approximately one-tenth of that of barcode reading. In the catheterization laboratory, a system consisting of a cartel management system utilizing bar codes and an RFID-compatible inventory management cabinet was introduced. The system eliminates the need to cut and paste packages onto vouchers after the cases are completed and digitizes the data sent to the medical affairs department for secure billing. We are implementing this system at many facilities, and, in addition to improving the work of nurses, we are taking new steps to improve hospital management through data linkage.

Internet of things-based approach for glycemic control in people with type 2 diabetes: A randomized controlled trial.

AIMS: The utilization of long-term effect of internet of things (IoT) on glycemic control is controversial. This trial aimed to examine the effect of an IoT-based approach for type 2 diabetes. MATERIALS AND METHODS: This randomized controlled trial enrolled 1,159 adults aged 20-74 years with type 2 diabetes with a HbA1c of 6.0-8.9% (42-74 mmol/mol), who were using a smartphone on a daily basis were randomly assigned to either the IoT-based approach group (ITG) or the control group (CTG). The ITG were supervised to utilize an IoT automated system that demonstrates a summary of lifelogging data (weight, blood pressure, and physical activities) and provides feedback messages that promote behavioral changes in both diet and exercise. The primary end point was a HbA1c change over 52 weeks. RESULTS: Among the patients, 581 were assigned to the ITG and 578 were in the CTG. The changes in HbA1c from baseline to the final measurement at 52 weeks [mean (standard deviation)] were -0.000 (0.6225)% in ITG and - 0.006 (0.6449)% in CTG, respectively (P = 0.8766). In the per protocol set, including ITG using the IoT system almost daily and CTG, excluding those using the application almost daily, the difference in HbA1c from baseline to 52 weeks were -0.098 (0.579)% and 0.027 (0.571)%, respectively (P = 0.0201). We observed no significant difference in the adverse event profile between the groups. CONCLUSIONS: The IoT-based approach did not reduce HbA1c in patients with type 2 diabetes. IoT-based intervention using data on the daily glycemic control and HbA1c level may be required to improve glycemic control.

The association between antipyretic analgesics use and SARS-CoV-2 antibody titers following the second dose of the BNT162b2 mRNA vaccine: An observational study.

Antipyretic analgesics are used to manage and control symptoms occurring after vaccination, but may hamper immunogenicity or vaccine efficacy. We examined the association between prophylactic or therapeutic use of antipyretic analgesics and SARS-CoV-2 antibody titers for vaccine recipients. Data were obtained from 1,498 staff members of a medical and research institution in Tokyo, Japan, who had received the second dose of the BNT162b2 vaccine. We quantitatively measured anti-SARS-CoV-2 spike protein IgG titers in the participants three months after vaccination. The prophylactic and therapeutic use of antipyretic analgesics was ascertained via a questionnaire. A linear regression model was used to examine the association between antipyretic analgesic use and log-transformed anti-SARS-CoV-2 spike protein IgG titers. Based on model parameters, we estimated geometric mean titers (GMT) and the corresponding 95 % confidence intervals (CI). The results showed that IgG titers in vaccine recipients who used antipyretic analgesics therapeutically was higher than the titers in those who did not (geometric mean ratio [GMR] = 1.26, 95 % CI = 1.17-1.34) with GMTs being 6,147 (95 % CI = 5,833-6,460) and 4,895 (95 % CI = 4,676-5,115) for those who used antipyretic analgesics therapeutically and those who did not, respectively. The association was attenuated, but remained statistically significant after adjusting for symptoms (GMR = 1.14, 95 % CI = 1.06-1.23). We did not find any evidence of significant association in relation to the prophylactic use of antipyretic analgesics (GMR = 0.96, 95 % CI = 0.84-1.10), with GMTs being 5,245 (95 % CI = 4,577-5,913) and 5,452 (95 % CI = 5,258-5,645) for those who used antipyretic analgesics prophylactically and those who did not, respectively. In conclusion, we did not find any evidence of suppression of the humoral response after the second dose of SARS-CoV-2 vaccination by prophylactic or therapeutic use of antipyretic analgesics.

Association of COVID-19-related discrimination with subsequent depression and suicidal ideation in healthcare workers.

Previous cross-sectional studies showed that COVID-19-related discrimination against healthcare workers was linked to depression. However, no study has examined the longitudinal association that allows causal interpretations. This prospective cohort study aimed to examine whether COVID-19-related discrimination at baseline is associated with depression and suicidal ideation several months later. Data were collected from October 2020 to July 2021. Multivariable logistic regression was performed. Fixed effects models were used to control for the effect of hospitals (Level 2 variable). Adjustments also included age, sex, living alone, alcohol consumption, exercise, BMI, working hours, comorbidity, and frontline worker status (Level 1 variables). Multiple sensitivity analyses were conducted to examine if the results substantially changed and were robust to unmeasured confounding. Multiple imputation for missing data was conducted via chained equations. As the final sample, 2862 healthcare workers without depression at baseline were studied. A total of 269 individuals (9.4%) experienced COVID-19-related discrimination. Depression was suggested in 205 participants (7.2%), and suicidal ideation in 108 participants (3.8%). In the adjusted models, COVID-19-related discrimination was significantly associated with subsequent depression (OR = 2.18, 95% CI = 1.39 to 2.90) and suicidal ideation (OR = 2.07, 95% CI = 1.22 to 3.50). Multiple sensitivity analyses verified the results. COVID-19-related discrimination results in depression and suicidal ideation in healthcare workers. Interventions to prevent such discrimination against healthcare workers, e.g., anti-discrimination campaigns, are crucial during the COVID-19 pandemic.

Underlying medical conditions and anti-SARS-CoV-2 spike IgG antibody titers after two doses of BNT162b2 vaccination: A cross-sectional study.

Patients with underlying medical conditions are at high risk of developing serious symptoms of the coronavirus disease 2019 than healthy individuals; therefore, it is necessary to evaluate the immune response to vaccination among them to formulate precision and personalized vaccination strategies. However, inconsistent evidence exists regarding whether patients with underlying medical conditions have lower anti-SARS-CoV-2 spike IgG antibody titers. We performed a cross-sectional study enrolling 2762 healthcare workers who received second doses of BNT162b2 vaccination from three medical and research institutes between June and July, 2021. Medical conditions were surveyed by a questionnaire, and spike IgG antibody titers were measured with chemiluminescent enzyme immunoassay using serum collected on the median of 62 days after the second vaccination. Multilevel linear regression model was used to estimate geometric mean and ratio of mean (95% confidence interval, CI) for the presence and absence of medical conditions and treatments. Among all participants (median age, 40 years [interquartile range, 30-50]; male proportion, 29.4%), the prevalence of hypertension, diabetes, chronic lung disease, cardiovascular disease, and cancer was 7.5%, 2.3%, 3.8%, 1.8%, and 1.3%, respectively. Patients with treated hypertension had lower antibody titers than those without hypertension; the multivariable-adjusted ratio of mean (95% CI) was 0.86 (0.76-0.98). Patients with untreated and treated diabetes had lower antibody titers than those without diabetes; the multivariable-adjusted ratio of mean (95% CI) was 0.63 (0.42-0.95) and 0.77 (0.63-0.95), respectively. No substantial difference was observed between the presence or absence of chronic lung disease, cardiovascular disease, or cancer. Patients with untreated hypertension and patients with untreated and treated diabetes had lower spike IgG antibody titers than participants without those medical conditions, suggesting that continuous monitoring of antibody titers and further booster shots could be necessary to maintain adaptive immunity in patients with hypertension or diabetes.

Impact of COVID-19 pandemic on behavioral changes and glycemic control and a survey of telemedicine in patients with diabetes: A multicenter retrospective observational study.

AIMS/INTRODUCTION: To investigate whether the COVID-19 pandemic affected behavioral changes and glycemic control in patients with diabetes and to conduct a survey of telemedicine during the pandemic. MATERIALS AND METHODS: In this retrospective study, a total of 2,348 patients were included from 15 medical facilities. Patients were surveyed about their lifestyle changes and attitudes toward telemedicine. Hemoglobin A1c (HbA1c) levels were compared among before (from June 1 to August 31, 2019) and in the first (from June 1 to August 31, 2020) and in the second (from June 1 to August 31, 2021) year of the pandemic. A survey of physician attitudes toward telemedicine was also conducted. RESULTS: The HbA1c levels were comparable between 2019 (7.27 ± 0.97%), 2020 (7.28 ± 0.92%), and 2021 (7.25 ± 0.94%) without statistical difference between each of those 3 years. Prescriptions for diabetes medications increased during the period. The frequency of eating out was drastically reduced (51.7% in 2019; 30.1% in 2020), and physical activity decreased during the pandemic (48.1% in 2019; 41.4% in 2020; 43.3% in 2021). Both patients and physicians cited increased convenience and reduced risk of infection as their expectations for telemedicine, while the lack of physician-patient interaction and the impossibility of consultation and examination were cited as sources of concern. CONCLUSIONS: Our data suggest that glycemic control did not deteriorate during the COVID-19 pandemic with appropriate intensification of diabetes treatment in patients with diabetes who continued to attend specialized diabetes care facilities, and that patients and physicians shared the same expectations and concerns about telemedicine.

Association between eating balanced meals and depressive symptoms in Japanese hospital workers during the COVID-19 pandemic.

AIM: While accumulating evidence suggests a protective role of healthy diet against depression, evidence on this issue is limited among healthcare workers combating COVID-19 pandemic. The aim of this study was to determine the cross-sectional association between frequency of balanced meal consumption and depressive symptoms among Japanese hospital workers during the COVID-19 pandemic. METHODS: Participants were 2,457 workers of the National Center for Global Health and Medicine who responded to a questionnaire survey in October or December 2020. Depressive symptoms were assessed using the patient health questionnaire-9 (PHQ-9). The number of days per week of eating two or more balanced meals was categorized into four from ≤1 day/week to daily. The association between frequency of balanced meal consumption and depressive symptoms was assessed using logistic regression analysis, with adjustment for lifestyle and COVID-19-related factors. RESULTS: The prevalence of depressive symptoms was 14.8%. The odds of depressive symptoms increased with decreasing frequency of balanced meal consumption. The multivariable-adjusted odds ratios (95% confidence intervals) of depressive symptoms were 1.00 (reference), 1.09 (0.75-1.58), 1.62 (1.17-2.24), and 2.21 (1.54-3.17) for balanced meal consumption categories of daily, 4-5 days/week, 2-3 days/week, and ≤1 day/week, respectively (P for trend<0.001). CONCLUSIONS: Our results suggest that infrequent consumption of well-balanced meal is associated with increased depressive symptoms among hospital workers during the COVID-19 pandemic.

Sex-associated differences between BMI and SARS-CoV-2 antibody titers following the BNT162b2 vaccine.

OBJECTIVE: This study investigated the sex-associated difference in the impact of obesity on antibody response to a COVID-19 vaccine. METHODS: This study included 2,435 health care workers who received two doses of the BioNTech, Pfizer (BNT162b2) vaccine and participated in a serological survey, during which they were tested for anti-SARS-CoV-2 spike immunoglobin G (IgG) antibodies and asked for information on height, weight, and vaccination history via a questionnaire. Multivariable linear regression analysis was used to estimate the geometric mean titers (GMT) of antibodies for each sex and BMI category. RESULTS: The relationship between BMI and anti-SARS-CoV-2 spike IgG titers markedly differed by sex (p value for interaction = 0.04). Spike IgG antibody titers tended to decrease with increasing BMI in men (p value for trend = 0.03); GMT (95% CI) were 6,093 (4,874-7,618) and 4,655 (3,795-5,708) for BMI < 18.5 and ≥30 kg/m2 , respectively. In contrast, spike IgG antibody titers did not significantly differ across BMI categories in women (p value for for trend = 0.62); GMT (95% CI) were 6,171 (5,714-6,665) and 5,506 (4,404-6,883) for BMI <18.5 and ≥30, respectively. CONCLUSIONS: Higher BMI was associated with lower titers of SARS-CoV-2 spike antibodies in men, but not in women, suggesting the need for careful monitoring of vaccine efficacy in men with obesity, who are at high risk of severe COVID-19 outcomes.

Association between chronic physical conditions and depressive symptoms among hospital workers in a national medical institution designated for COVID-19 in Japan.

OBJECTIVE: This study aimed to investigate the cross-sectional association between the presence of chronic physical conditions and depressive symptoms among hospital workers at a national medical institution designated for COVID-19 treatment in Tokyo, Japan. We also accounted for the combined association of chronic physical conditions and SARS-CoV-2 infection risk at work in relation to depressive symptoms, given that occupational infection risk might put additional psychological burden among those with chronic physical conditions with risk of severe COVID-19 outcome. METHODS: The study sample consisted of 2,440 staff members who participated in a health survey conducted at the national medical institution during period between October 2020 and December 2020. Participants who reported at least one chronic physical condition that were deemed risk factors of severe COVID-19 outcome were regarded as having chronic physical conditions. Depressive symptoms were assessed using the patient health questionnaire-9 (PHQ-9). We performed logistic regression analysis to assess the association between chronic physical conditions and depressive symptoms. RESULTS: Our results showed that the presence of chronic physical conditions was significantly associated with depressive symptoms (odds ratio (OR) = 1.49, 95% confidence interval (CI) = 1.10-2.02). In addition, the prevalence of depressive symptoms was significantly higher among healthcare workers with chronic physical conditions who were at a higher occupational infection risk (OR = 1.81, 95% CI = 1.04-3.16). CONCLUSION: Our findings suggest the importance of providing more assistance to those with chronic physical conditions regarding the prevention and control of mental health issues, particularly among frontline healthcare workers engaging in COVID-19-related work.

Association Between Adherence to Healthy Lifestyles and Depressive Symptoms Among Japanese Hospital Workers During the COVID-19 Pandemic.

The objective of this study was to investigate the association between adherence to healthy lifestyles (as measured by the healthy lifestyle index [HLI]) and depressive symptoms among staff members at a large national medical institution in Tokyo, Japan, during the coronavirus disease 2019 (COVID-19) pandemic. The study sample consisted of 1228 staff members aged between 21 and 73 years who participated in a cross-sectional survey conducted in July 2020. We constructed the HLI by assigning one point to each healthy lifestyle factor: normal body mass index, sufficient physical activity, non-smoking status, non-to-moderate alcohol consumption, and sufficient sleep duration. The multivariate adjusted odds ratios for depressive symptoms were 1.00 (reference), 0.71, 0.66, and 0.56 for participants with HLI scores of 0 to 2, 3, 4, and 5, respectively. The present study suggests the role of healthy lifestyles in mental health among hospital staff working during the pandemic.

Association between engagement in COVID-19-related work and depressive symptoms among hospital workers in a designated COVID-19 hospital in Japan: a cross-sectional study.

OBJECTIVES: To examine whether engagement in COVID-19-related work was associated with an increased prevalence of depressive symptoms among the staff members working in a designated medical institution for COVID-19 in Tokyo, Japan. DESIGN: A cross-sectional study. SETTING: Data were obtained from a health survey conducted in July 2020 among the staff members of a designated medical institution for COVID-19 in Tokyo, Japan. PARTICIPANTS: A total of 1228 hospital workers. EXPOSURE OF INTEREST: Engagement in COVID-19-related work (qualitatively (ie, the risk of SARS-CoV-2 infection at work or affiliation to related departments) as well as quantitatively (ie, working hours)) and job categories. OUTCOME MEASURES: Depressive symptoms. RESULTS: There was no significant association between depressive symptoms and engagement in work with potential exposure to SARS-CoV-2 or affiliation to COVID-19-related departments. However, working for longer hours in March/April, when Japan witnessed a large number of infected cases, was significantly associated with depressive symptoms (≥11 hours/day: prevalence ratio (PR)=1.45, 95% CI=1.06 to 1.99, compared with ≤8 hours/day). Nurses were more likely to exhibit depressive symptoms than did doctors (PR=1.70, 95% CI=1.14 to 2.54). CONCLUSIONS: This study suggests that the risk of SARS-CoV-2 infection at work or having an affiliation to related departments might not be linked with a higher prevalence of depressive symptoms among Japanese hospital workers; contrarily, long working hours appeared to increase the prevalence of depressive symptoms.

Consistency of the results of rapid serological tests for SARS-CoV-2 among healthcare workers in a large national hospital in Tokyo, Japan.

We assessed the consistency of seropositive results of three rapid immunoassays (Kits A, B, and C) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compared to highly accurate serological tests (Abbott and Roche) among healthcare workers in a hospital in Tokyo. The seroprevalence of SARS-CoV-2 immunoglobulin G was 0.41%, 2.36%, and 0.08% using Kits A, B, and C, respectively. Of the 51 samples that were seropositive on any rapid test, all were seronegative on both the Abbott and the Roche assays. Given that the seroprevalence of SARS-CoV-2 immunoglobulin G varied widely according to the choice of rapid test and the rapid test results were inconsistent with the results of highly accurate tests, the diagnostic accuracy of rapid serological tests for SARS-CoV-2 should be assessed before introducing these tests for point-of-care testing or surveillance.

Development of Patient State Model to Overview Clinical Registry Database.

By applying the Bayesian network method to the clinical registry database J-DREAMS (Japan Diabetes compREhensive database project based on an Advanced electronic Medical record System), we have developed a reference model that summarizes the exploration of the patient group's state and facilitates a bird's-eye view. This visualization method would help registry researchers to screen the registry database.

Development of case-based medication alerting and recommender system: a new approach to prevention for medication error.

The purpose of this study was to develop a new alerting and recommender system for preventing medication errors. In recent years, alerting systems have been widely implemented, but because these systems apply a same static threshold for all patients in all cases, they produce excessive alerts and subject physicians to "alert fatigue". We believe that the most commonly-written prescription for a patient's status is the safest one. From this standpoint, we developed a real-time case-based medication alerting and recommender system linked to a database of past prescriptions. When a physician issues his or her prescription, our system dynamically compares it with past ones for similar patients in the database. An analysis of the 10 most frequently-used drugs in the University of Tokyo Hospital revealed that our system reduced the number of false alerts compared to the traditional static alert method. Our system contributes to the creation of alerts that are appropriate for patients' clinical conditions and based on physicians' empirical discretion.