Introduction of reduced rank regression and development of a user-written Stata package / 中华流行病学杂志

Reduced rank regression is an extended multivariate linear regression model with the function of dimension reduction. It has been more and more widely used in nutritional epidemiology research to understand people's dietary patterns in recent years. However, there has been no existing Stata package or command to implement reduced rank regression independently. Therefore, we developed a new user-written package named "rrr" for its implementation in Stata. This paper summarizes the methodology of reduced rank regression, the development and functions of the Stata rrr package and its application in the China Kadoorie Biobank dataset, with the aim of facilitating the future wide use of this statistical method in epidemiology and public health research.

Clinical value of myoglobin in predicting multiple organ dysfunction in wasp sting patients / 中华急诊医学杂志

Objective:To investigate the clinical features and risk factors of multiple organ dysfunction syndrome (MODS) caused by wasp sting.Methods:A retrospective cohort study was conducted to collect the general data of wasp sting patients who had a clear history of wasp sting disease and clinical manifestations from June 2016 to December 2020 and were first diagnosed as wasp sting in hospital. Patients with hematological diseases, malignant tumors, severe liver and kidney dysfunction, cardiac insufficiency, and patients who had received hormone therapy before admission were excluded. Patients who were unable to obtain effective laboratory results due to hemolysis or other reasons within 48 h of admission were also excluded. The white blood cell count (WBC), neutrophil count (NEU), lymphocyte count (LYM), hemoglobin count (HB), myoglobin (Mb/MYO), activated partial thromboplastin time (APTT), albumin (ALB), K, Na, and Cl of the blood samples collected within 48 h after admission were recorded. Patients were divided into the MODS group and non-MODS group according to whether MODS occurred during hospitalization. Uni- and multivariate analysis were used to analyze the factors affecting the occurrence of MODS in wasp sting patients during hospitalization, and the receiver operating characteristic (ROC) curve was plotted to evaluate the predictive effect of myoglobin level on the occurrence of MODS in wasp sting patients during hospitalization.Results:Mb, WBC, NEU, APTT and serum potassium in the MODS group [3890.00 (1416.90-4057.00) ng/mL, (21.99 ± 8.18) × 10 9/L, (19.61 ± 7.33)× 10 9/L, (93.75 ± 45.77) s, and (4.99 ± 0.95) mmol/L] were significantly higher than those in the non-MODS group [73.50 (34.30-264.20) ng/mL, (13.40 ± 4.14)× 10 9/L, (11.18±4.73)× 10 9/L, (37.00 ± 17.16) s, and (4.05 ± 0.56) mmol/L] (all P < 0.05); blood chlorine and ALB [(101.50 (98.25-105.00) mmol/L and (35.36 ± 6.44) g/L)] were significantly lower than those in the non-MODS group [(105.00 (103.00-107.00) mmol/L and (40.71 ± 5.48) g/L)] (all P < 0.05). Multivariate logistic regression analysis showed that NEU ( OR = 0.729, 95% CI: 0.542~0.981), Mb ( OR = 0.999, 95% CI: 0.998~1.000), and APTT ( OR = 0.951, 95% CI: 0.921~0.982) were independent risk factors for MODS in wasp sting patients. ROC curve analysis showed that NEU, Mb and APTT could be used to evaluate the occurrence of MODS in wasp sting patients. Among them, Mb had the highest predictive value (AUC = 0.950, 95 % CI: 0.891~0.982). The optimal cutoff value of Mb for predicting the occurrence of MODS in wasp sting patients was 515.30 ng/mL, and the corresponding sensitivity and specificity were 90.62% and 87.23%, respectively. Conclusion:Mb is an independent risk factor for MODS in wasp sting patients, which can be used as a good predictor of MODS in wasp sting patients.

Diagnostic value of hysterosalpingography / 中国实用妇科与产科杂志

Tubal infertility accounts for 25%-35% offemale infertility and hysterosalpingography(HSG)isthe first line diagnostic method.In this article,we willdiscuss the HSG diagnostic criteria of tubal partialocclusion,tubal proximal occlusion,salpingitis isth-mica nodosum,hydrosalpinx,pelvic adhesion andpelvic tuberculosis in order to provide guidance in theclinical diagnosis and prognosis evaluation.

Endometrial MicroRNA Signature during the Window of Implantation Changed in Patients with Repeated Implantation Failure / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>At present, a diagnostic tool with high specificity for impaired endometrial receptivity, which may lead to implantation failure, remains to be developed. We aimed to assess the different endometrial microRNA (miRNA) signatures for impaired endometrial receptivity by microarray analysis.</p><p><b>METHODS</b>A total of 12 repeated implantation failure (RIF) patients and 10 infertile patients, who conceived and delivered after one embryo transfer attempt, were recruited as RIF and control groups, respectively. Endometrial specimens from the window of implantation (WOI) were collected from these two groups. MiRNA microarray was conducted on seven and five samples from the RIF and control groups, respectively. Comparative, functional, and network analyses were performed for the microarray results. Quantitative real-time polymerase chain reaction (PCR) was performed on other samples to validate the expression of specific miRNAs.</p><p><b>RESULTS</b>Compared with those in the control group, the expression levels of 105 miRNAs in the RIF group were found to be significantly up- or down-regulated (at least 2-fold) by microarray analysis. The most relevant miRNA functional sets of these dysregulated miRNAs were miR-30 family, human embryonic stem cell regulation, epithelial-mesenchymal transition, and miRNA tumor suppressors by tool for annotations of microRNA analysis. Network regulatory analysis found 176 miRNA-mRNA interactions, and the top 3 core miRNAs were has-miR-4668-5p, has-miR-429, and has-miR-5088. Expression levels of the 18 selected miRNAs in new samples by real-time PCR were found to be regulated with the same trend, as the result of microarray analysis.</p><p><b>CONCLUSIONS</b>There is a significant different expression of certain miRNAs in the WOI endometrium for RIF patients. These miRNAs may contribute to impaired endometrial receptivity.</p>

Distributions and associations between duration of sleep, daytime naps and insomnia symptoms among Chinese adults / 中华流行病学杂志

Objective To investigate the distribution of sleep duration,daytime naps habits,and insomnia-related symptoms among participants from the China Kadoorie Biobank (CKB) study,and to examine the associations between the sleep-associated factors.Methods A self-designed computer-based questionnaire was adopted to collect social-demographic information and lifestyle-related factors of the participants.A total of 452 829 Chinese adults aged 30-79 years,without self-reported histories of coronary heart disease,stroke,chronic obstructive pulmonary diseases or cancer,were included in this study.General linear regression and multinomial logistic regression models were used to estimate the distributions on duration of sleep,daytime naps habits,and insomnia-related symptoms in different populations,after adjusted for gender,age,and residential regions.Gender-specific logistic regression model was adopted to examine the associations between the above mentioned sleep-related factors.Results The average sleep duration of the participants was 7.41 hours per day,with 20.3％ of them having daytime naps all year round,but 40.1％ only had daytime naps in summer,and 39.6％ had no habits of daytime naps.11.0％,10.0％,and 2.1％ of the participants reported having had symptoms as difficulty in falling asleep,waking up too early or with daytime dysfunction,respectively.There were significant differences on the distributions in sleep-related factors between participants with different gender,age,residential areas,education levels,household income,and marital status (P＜0.05).Results from the logistic regression showed that longer sleep duration was associated with lower risks of insomnia-related symptoms trend (P＜0.001).Factor as without habits of daytime naps seemed to be associated with higher risks of insomnia-related symptoms (P＜0.05).Participants with longer sleep duration were more likely to have the habit of taking daytime naps (P＜0.05).Conclusions The distributions of sleep duration,habits on daytime naps and insomnia-related symptoms varied according to the differences on social-demographic factors.There were associations existed between the sleeping-related factors,which would influence the promotion on optimal sleep duration and better quality of sleep.

Distributions and associations between duration of sleep, daytime naps and insomnia symptoms among Chinese adults / 中华流行病学杂志

Objective To investigate the distribution of sleep duration,daytime naps habits,and insomnia-related symptoms among participants from the China Kadoorie Biobank (CKB) study,and to examine the associations between the sleep-associated factors.Methods A self-designed computer-based questionnaire was adopted to collect social-demographic information and lifestyle-related factors of the participants.A total of 452 829 Chinese adults aged 30-79 years,without self-reported histories of coronary heart disease,stroke,chronic obstructive pulmonary diseases or cancer,were included in this study.General linear regression and multinomial logistic regression models were used to estimate the distributions on duration of sleep,daytime naps habits,and insomnia-related symptoms in different populations,after adjusted for gender,age,and residential regions.Gender-specific logistic regression model was adopted to examine the associations between the above mentioned sleep-related factors.Results The average sleep duration of the participants was 7.41 hours per day,with 20.3％ of them having daytime naps all year round,but 40.1％ only had daytime naps in summer,and 39.6％ had no habits of daytime naps.11.0％,10.0％,and 2.1％ of the participants reported having had symptoms as difficulty in falling asleep,waking up too early or with daytime dysfunction,respectively.There were significant differences on the distributions in sleep-related factors between participants with different gender,age,residential areas,education levels,household income,and marital status (P＜0.05).Results from the logistic regression showed that longer sleep duration was associated with lower risks of insomnia-related symptoms trend (P＜0.001).Factor as without habits of daytime naps seemed to be associated with higher risks of insomnia-related symptoms (P＜0.05).Participants with longer sleep duration were more likely to have the habit of taking daytime naps (P＜0.05).Conclusions The distributions of sleep duration,habits on daytime naps and insomnia-related symptoms varied according to the differences on social-demographic factors.There were associations existed between the sleeping-related factors,which would influence the promotion on optimal sleep duration and better quality of sleep.

Associations between dormitory environment/other factors and sleep quality of medical students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the sleep quality and related factors among medical students in China, understand the association between dormitory environment and sleep quality, and provide evidence and recommendations for sleep hygiene intervention.</p><p><b>METHODS</b>A total of 555 undergraduate students were selected from a medical school of an university in Beijing through stratified-cluster random-sampling to conduct a questionnaire survey by using Chinese version of Pittsburgh Sleep Quality Index (PSQI) and self-designed questionnaire. Analyses were performed by using multiple logistic regression model as well as multilevel linear regression model.</p><p><b>RESULTS</b>The prevalence of sleep disorder was 29.1%(149/512), and 39.1%(200/512) of the students reported that the sleep quality was influenced by dormitory environment. PSQI score was negatively correlated with self-reported rating of dormitory environment (γs=-0.310, P<0.001). Logistic regression analysis showed the related factors of sleep disorder included grade, sleep regularity, self-rated health status, pressures of school work and employment, as well as dormitory environment. RESULTS of multilevel regression analysis also indicated that perception on dormitory environment (individual level) was associated with sleep quality with the dormitory level random effects under control (b=-0.619, P<0.001).</p><p><b>CONCLUSIONS</b>The prevalence of sleep disorder was high in medical students, which was associated with multiple factors. Dormitory environment should be taken into consideration when the interventions are taken to improve the sleep quality of students.</p>

Analysis of the reliability and validity of the Chinese version of Pittsburgh sleep qua-lity index among medical college students / 北京大学学报(医学版)

Objective:To evaluate the reliability and validity of the Chinese version of Pittsburgh sleep quality index (PSQI)among the medical students.Methods:A total of 603 undergraduate students were selected from a medical school in Beijing using a stratified-cluster random-sampling strategy,who were assessed by using the Chinese version of PSQI.Then 1 71 subjects were randomly selected to retest about 1 month later,using a variety of psychometric properties to evaluate reliability and validity of the scale. Results:The average of global PSQI scores was 5.38 ±2.34,the overall Cronbach’s αcoefficient of all the scale items was 0.734,the half-split reliability coefficient was 0.655;the test-retest correlation coef-ficient was 0.530 for global PSQI score,and there was no statistically significant difference before and af-ter (P >0.05).As for the construct validity,confirmatory factor analysis results indicated that the two factor model (containing sleep efficiency factor and sleep quality factor)was the optimal model (good-ness-of-fit index 0.949,root of the mean square residual 0.083,comparative fit index 0.699),and the factor loading for “hypnotic drug use”was the lowest.Using subjective sleep quality of the students as the criteria,the global PSQI score was statistically different between the criteria-based groups (P <0.001 ).And the area under the receiver operating characteristics (ROC)curve which was plotted using the global score of PSQI was 0.908 (95%CI:0.880 -0.936).Conclusion:The Chinese version of PSQI has been verified,having good reliability and validity among the medical students,and is an effec-tive tool to investigate and screen the sleep quality of medical students in China.

Assessment of the Reliability and Validity of the Clinical Reception Attitude Scale / 中国医学伦理学

Objective:To evaluate the reliability and validity of the Clinical Reception Attitude Scale .Meth-ods:Based on the survey of 311 outpatients from 4 first-class hospitals , the test-retest reliability , internal con-sistency , construct validity , criterion validities and discriminant validity of the scale was tested .Results:The test-retest reliability was 0.901, the internal consistency was 0.973, 4 common factors accounted for 80.0%of the total variation, the items of which matched the construct of the scale , the criterion validities were 0.856 and 0 .810 , the discriminant validity was good .Conclusions: The results indicated the Clinical Reception Attitude Scale had good reliability and validity .The adjusted scale is an effective tool for the investigation of clinical recep-tion attitude of doctors in China .

The Development of a Scale of Doctors′attitude in outpatient encounter / 中国医学伦理学

The final scale came into being through the process of compiling items with the use of document method and Delphi method, assessing the reliability and validity realized by application of multiple linear regression analysis, Crowns Bach coefficient, correlation coefficient methods and so forth.19 items and 4 dimensions contai-ning communication skills, care, respect and sense of responsibility comprise this clinical reception attitude scale. The scale is qualified to serve as an assessment tool for researching doctor′s attitude, having various merits inclu-ding high consistency among items and cogent dimension setting, whose total score can desirably represent clinical doctor′s attitude towards out-patients.