Objective To explore the processing Methods of big data of hospital information systems(HIS) and analyze the characteristics and trends of outpatient visits and medical services in a tertiary pediatric hospital in Shanghai during the past 10 years. Methods Data were extracted from the database of outpatient registry in HIS from 2009 to 2018. Data cleaning (diagnosis, address, replication, outliers, and missing data), data assembly (linkage of database), data reduction, data anonymization and data audit were conducted according to the procedure of big data. We analyzed the characteristics and trends of outpatient visits and medical services. Results The total outpatient visits from 2009 to 2018 were 20,775,899 and 18,242,822 visits were included in this study. Males were 4,656,843 accounting for 57.42%. Patients under 1 year old, from 1 to 3 years old, from 3 to 7 years old and from 7 to 18 years accounted for 9.57%,40.94%, 24.82% and 24.67% respectively. The missing data rate of diagnosis, address, and name of doctors was 5.92%, 45.31% and 28.61%,respectively. There were no significant differences in the percentage of sex and age in different years among the population with missing data. The average increasing rate of outpatient visits was 5.22% in the past 10 years. The increasing rate of 2012 and 2014 were 11.22% and 10.93% respectively, compared with the same period of last year. The increasing rate slowed down to 2.90% after 2015. The distribution of outpatient address showed the trends of expansion from the east of China to the South-west, North-west, South, Middle and North-east. The average workload of a doctor was 51 visits in a day. According to professional titles, there were 63, 54, and 45 visits per day for junior, intermediate, and senior doctors, respectively. The number of specialty clinics increased from 46 in 2009 to 180 in 2018 and serviced the 68.12% of outpatient visits. The number of specific disease clinics increased from 16 in 2009 to 142 in 2018. Conclusion The big data of outpatient visits in a tertiary pediatric hospital(National Children's Medical Center) in China showed that there was a sustainable upward trend in outpatient visits; the origin of patients expanded from Shanghai to the whole of China; the average visits for a single physician were lower than that of the country. Specialized clinics in specialties or diseases are an important trends for the development of children's hospitals.

Objective To explore the causal association between birth weight and childhood obesity by using the GWAS data and the Mendelian randomization (MR) method.Methods Based on the genetic data published by the Early Growth Genetics Consortium (EGG) (data acquisition time is October 20, 2018), the SNP with statistically significant association with birth weight was screened by MR-base platform. As instrumental variables (screening parameters P<5×10 ^-8, linkage disequilibrium r²<0.1), birth weight and childhood obesity were determined by inverse variance weighted analysis (IVW), weighted median method and MR-Egger method, respectively (definition of childhood obesity: BMI≥95%). Forest maps and scatter plots were also applied.Results A total of 33 SNPs related to birth weight were screened. A total of 5,530 obese children and 8,318 normal children were included. IVW analysis: OR=1.79, 95% CI: 1.29~2.47, P=4.24×10 ^-4; weighted median method: OR=1.30, 95% CI: 0.81~2.08, P=0.27; MR-Egger method: OR=1.73, 95% CI: 0.58~5.20, P=0.36. The result of IVW in the forest map showed that the genetic susceptibility of childhood obesity was related to the birth weight level. rs7964361, rs11765649, rs3780573 and rs1351394 showed that birth weight and childhood obesity were statistically significant. The scatter plot showed that the causal correlation estimates for the IVW method, the MR-Egger method, and the weighted median method were similar.Conclusion IVW analysis showed that there was a strong correlation between birth weight and childhood obesity, but the other two statistical methods found that the difference was not statistically significant, so the causal association remained to be supported by further evidence.

Objective To evaluate the applied meaning of Ig/TCR gene rearrangements by RQ-PCR for minimal residual disease(MRD) detection in childhood acute lymphoblastic leukemia （ALL）. Methods ①PCR detection of Ig/TCR gene rearrangements of ALL children was performed at diagnosis. ②The clonality of Ig/TCR gene rearrangements was analyzed by GeneScan. ③The sequence of monoclonal PCR products was checked to determine the patient-specific sequence as MRD detection target followed by the design of patient-specific primers and probes, and RQ-PCR quantification at different therapy phases. Results Eighty six children diagnosed as ALL were included. ①At least one type of Ig/TCR rearrangement was found in 96.5% (83/86) ALL children. ②91.8% (56/61) ALL children were detected to have at least one monoclonal Ig/TCR gene rearrangement. The detection rates for monoclonal, oligoclonal and polyclonal Ig/TCR rearrangement were 58.1%, 30.8% and 11.0% with significant difference(P<0.001). ③For 22 continuous complete remission(CCR) cases, the Ig/TCR gene rearrangement expression consistently decreased as therapy continued, and before maintaining therapy, all tested MRD cases were detected to be MRD negative; For 4 relapse cases, MRD was persistently positive from beginning of induced remission to relapse, and clinically the average relapse time was 3.75 months (ranging from 2 to 8 months) since the relative expression of Ig/TCR rearrangement started increasing. Conclusions Surveillance of ALL children's MRD level detected by RQ-PCR with Ig/TCR gene rearrangement as targets, is a potentially useful assay for evaluation and assessment of therapy effect and relapse prediction.

Background：The Swanson, Nolan, and Pelham, version scale (SNAP-Ⅳ) is the most widely used assessment tool for evaluating the core symptoms of attention-deficit/hyperactivity disorder (ADHD) in children. However, there is still a lack of systematic review of the measurement properties of the SNAP-Ⅳ scale, which may introduce bias and potentially affect the assessment validity of the measurement tool. Objective：To evaluate the measurement properties of the SNAP-Ⅳ based on the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN), and to provide evidence-based measurement instrument recommendations for the screening, diagnosis and efficacy evaluation of children with ADHD. Design：Systematic review. Methods：Related literature was systematically searched in databases of China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database, China Biomedical Literature Database (CBM), PubMed, Cochrane Library, EMBASE, and Web of Science from the inception to April 21, 2022. Two reviewers independently screened the literature, and the measurement properties of the SNAP-Ⅳ scale were objectively evaluated according to the COSMIN manual. Main outcome measures：Content validity and internal consistency of the SNAP-Ⅳ scale. Results：A total of 14 studies involving 6 language versions were included. The content validity of the SNAP-Ⅳ scale was rated as "sufficient" (moderate quality evidence) in terms of relevance, comprehensiveness, and comprehensibility. However, there was no reported content on the development of the SNAP-Ⅳ scale. The parent and teacher versions of the SNAP-Ⅳ scale showed "sufficient" internal consistency (high-quality evidence). There was no high-quality evidence indicating "insufficient" measurement properties. The overall recommendation was classified as level A. Conclusion：The SNAP-Ⅳ scale is recommended for the screening, diagnosis, and treatment evaluation of children with ADHD, and its results can be considered reliable.

Background Despite that numerous researches have investigated the pathogenesis of Kawasaki disease (KD), including epidemiology, genetics, infection, immunity, and inflammation. However, the causes of KD is still not well underlined. Objective We analyzed the blood samples of KD patients and control cases using modified highthroughput metagenomics sequencing to identify the bacterial and viral composition and relative abundances, aiming to demonstrate the potential pathogenic virus of KD. Design Casecontrol study. Methods We collected the blood samples from KD patients and controls, then purification, extraction and sequencing of viruslike particles had been completed. After quality control of raw data, macrogenome was assembled by MEGAHIT software and species annotating was performed on kraken2. Obtaining relative abundance of each sample at different taxonomic levels (phylum, order, family, genus, and species), we normalized taxon abundance with the online tool Wekemo Bioincloud. The top 20 taxa were displayed and analyzed comparatively using linear discriminant analysis. LDA>2 was set as the criteria of significant differences in abundance between groups for filtering potential pathogenic species. Main outcome measures Relative abundance of each sample at different taxonomic levels (phylum, order, family, genus, and species). Results We found that there was little difference between KDs and the controls in terms of overall microorganism. Only phylum Cossaviricota and species Bacillussp Y1 were significantly different. However, there was a great significant difference between viral population annotations. The relative abundances of Uroviricota, Nucleocytoviricota, and Taleaviricota were significantly higher in controls compared with KD patients. Various genera, such as Orthohepadnavirus, Pegunavirus, Montyvirus, Orthonairovirus, Toursvirus, showed significantly higher relative abundance in KDs. In KD patients, the relative abundance of Woodchuckhepatitis virus, Propionibacterium virus (PHL112N00, ATCC29399BT, Pirate, and P105), Diadromus pulchellus toursvirus, and so on were significantly more abundant than that in controls. Conclusion Summarily, we screened out several candidates KD pathogenic viruses, like WHV, Orthonairovirus, and DpTV1. These viruses may be responsible for acute febrile illness or liver damage in KD patients, or they may be able to disrupt patients' immune systems, but further investigations are required.

The Appraisal of Guidelines for Research & Evaluation (AGREE) instrument has been the important standard for Clinical Practice Guideline appraisal, since released in 2003. The second version, AGREEⅡ was released in 2009. Some domestic researchers has translated and used the instruments. We want to explain each items of AGREE Ⅱ detailedly through appraising Chinese Clinical Practice Guidelines, hoping to provide reference for the domestic researchers understanding and using AGREEⅡ appropriately.

Background The collective living environment during the preschool period is associated with a high incidence of acute upper respiratory tract infections (AURTIs). Objective To explore the effectiveness of physiological saline nasal irrigation (seawater) in preventing AURTIs in healthy preschool children entering childcare centers, providing a theoretical basis for improving hygiene and healthcare in childcare institutions. Design Singlecenter randomized controlled trial (RCT). Methods Healthy children in the middle class of kindergartens were selected as the study subjects, and cluster random sampling was conducted at the class level. The study was not blinded. The intervention group received nasal care with seawater nasal irrigation at room temperature, with one spray before entering and leaving the kindergarten each day, for a semester of kindergarten attendance (192 times over 96 days). The operation was performed according to the recommended methods in the Expert Consensus on Nasal Saline Irrigation in Children with Upper Respiratory Tract Infections (2023). The control group received organized interventions when entering and leaving the kindergarten each day. The kindergarten healthcare doctors recorded nasal irrigation twice daily and adverse reactions. Interrupted nasal irrigation time, the first report of AURTIs, onset time of nasal symptoms, relief time, disappearance time, and withdrawal time were also recorded. Those meeting the following criteria were excluded: children in the intervention group with nasal irrigation interruption ≥1 week (including Saturdays and Sundays); children with absenteeism exceeding 20% of the school days during the study period (19 days); children who withdrew from the study halfway (e.g., transferring schools); children who used antibiotics, antiviral drugs, or antichlamydial infection drugs based on medical records during the study period; children whose first occurrence of AURTI or nasal symptoms was not reported to the kindergarten within 24 hours according to the CRF table. Main outcome measures Incidence of AURTIs (the number of children who developed AURTI within 48 hours of enrollment divided by the number of enrollees). Results A total of 234 children in the middle class of kindergartens who met the inclusion and exclusion criteria were included in the analysis, with 120 in the intervention group and 114 in the control group. There were no statistically significant differences in gender, age, weight, and actual days in kindergarten between the two groups of children. The incidence of AURTIs during the study period ［55 (45.8%) vs. 81 (71.0%)］and the average number of AURTIs ［(0.7±1.0) vs. (1.4±1.3)］ in the intervention group were significantly lower than those in the control group (P<0.05). There were no statistically significant differences in the incidence of AURTIs between boys and girls in the intervention group. It is the same with the control group. However, there were statistically significant differences in the incidence of AURTIs between two groups in both boys and girls. The intervention group showed statistically significant differences in the relief time ［(2.3±1.0 days) vs. (2.8±0.9 days)］ and disappearance time ［(5.4±1.1 days) vs. (5.8±1.0 days)］ of nasal symptoms compared to the control group. Three cases of mild nasal bleeding occurred in the intervention group, but nasal irrigation intervention continued because of the children's tolerance, and no nasal irritation or ear pain was found. Conclusion Physiological seawater nasal irrigation can reduce the incidence and frequency of AURTIs in healthy preschool children entering childcare centers. It can also effectively relieve nasal symptoms associated with AURTIs and shorten the duration of symptoms. The clinical operation is simple and convenient with few adverse reactions.

Background Trends in growth and development of children and adolescents are considered to be a " biological standard of living conditions", reflecting the combined effects of genetic trajectories, environmental factors centered on nutrition and disease, and socio-economic circumstances. Objective The aim of this study was to construct a non-invasive equation for the prediction of maturity offsets and to assess the level of physiological maturity of individuals through a longitudinal study. Design Mixed longitudinal study. Methods From the 2015-2021 cohort of the Child and Adolescent Growth and Development Longitudinal Study, children and adolescents with four or more monitoring records who could accurately calculate the age of peak height velocity (aPHV) were selected for the prediction of maturity offsets using the lasso method. After supplementing the data in 2022-2023, children and adolescents were selected based on the same selection criteria, and the equations were validated. All statistics were performed in R and GraphPad software. Main outcome Maturity offset equations. Results Male equation = -15.553 + 0.705 × age + 0.067 × sitting height + 0.063 × BMI, with a SEE of 0.625; female equation = -14.240 + 0.668 × age + 0.084 × sitting height + 0.002 × quetelet index, with a SEE of 0.542. These equations were more suitable for the current cohort of children and adolescents in Shanghai. Conclusion At the present period, children and adolescents still maintain the long-term trend of growth characterized by the advancement of the pubertal spurt. It is necessary to seize this strong momentum to give full expression to the growth potential and to promote the healthy development of the population. Maturity offset equations applicable to the current population could be adopted for the evaluation of individual physiological maturity, in order to achieve fair competition and early screening of sports talents during training and competition, and to promote the long-term development of youth sports literacy and ability level.

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Background: Sitting height and leg length are the useful indicators for the linear growth evaluation of children and adolescents, but the growth reference standards of the two indicators have not been reported. Objective: To study and formulate the growth reference of sitting height and leg length of Chinese children and adolescents aged 0-18 years. Design: A cross-sectional survey. Methods: Stature and sitting height of 92,494 healthy urban children aged 0-18 years were measured in two national surveys in 2005 in China—The National Survey on the Physical Growth and Development of Children in the Nine Cities of China (NSPGDC) and The Chinese National Survey on Students' Constitution and Health (CNSSCH). Leg length was calculated by height minus sitting height. Growth reference standards of sitting height and leg length were constructed using the LMS method. Main outcome measures: Reference values of sitting height and leg length. Results: The percentile and the Z-scores reference values of sitting height and leg length for Chinese boys and girls aged 0-18 years were shown and their growth charts were drawn. Sitting height increased about 14 cm, 6 cm and 4 cm during the first, second and third year after birth, respectively. After that, the annual increment of sitting height is nearly 2-3 cm. Then the increments became slightly higher at 11-13 years for boys and 9-11 years for girls and gradually became smaller and smaller. Sitting height nearly stopped increasing at the age of 17 years for boys and 15 years for girls. Leg length increased respectively about 11-12 cm and 6.5 cm during the first and second year after birth, then the annual increment was 4-5 cm during 2-5 years, and leg length stopped increasing nearly at 15 years for boys and 13 years for girls. Conclusion: The growth reference standards of sitting height and leg length were formulated, which provide more data and reference for perfecting the growth evaluation system of children and adolescents in China.

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Background: Great heterogeneity exists in studies on the relationship between adolescents' mental health and 24-h movement consisting of sleep, sedentary behavior, and physical activity. Therefore, it is difficult to obtain high-quality evidence synthesis sufficient to guide clinical practice. Objective: To summarize and evaluate the current status of research on the relationship between 24-hour movement (sleep, sedentary behavior, and physical activity) and mental health in children and adolescents, as well as the problems in research design, so as to provide a reference for future research. Design: Scoping review. Methods: PubMed, Embase, Web of Science, and CNKI databases were searched from the inception to September 28, 2022, with the keywords of sleep, sedentary behavior, physical activity, 24-h movement, mental health, and adolescents to identify research on the correlation or causal inference between 24-h movement and mental health in healthy children and adolescents. Data extraction forms for movement type, measurement methods, classification of measurement items, and specific item measurement were gradually refined in the process of data extraction and synthesis after reading the text title, abstract, and full text for screening. Main outcome measures: Study types and measurement instruments for the relationship between 24-h movement and mental health in adolescents. Results: A total of 927 articles were retrieved from the English and Chinese databases, and after de-duplication, initial screening and full-text screening, 55 articles were finally included with 45 (82%) cross-sectional studies and 10 prospective cohort studies; 47 (85%) subjective reports and 8 objective monitoring articles. For sleep, 54 described sleep duration and 4 assessed sleep quality, sleep latency, daytime sleepiness, and sleep disruption. For sedentary behavior, there were 50 subjective reports, 5 objective reports, and 46 studies about screen exposure. For physical activity, hours of moderate-to-vigorous physical activity were assessed in 47 subjective reports and 8 objective reports. A total of 32 studies focused on depression, 9 on anxiety, 5 on stress, and 35 on other mental health outcomes (positive mood, behavioral problems, life satisfaction or health-related quality of life, mental illness and symptoms, emotion regulation skills, and cell phone addiction). Forty-four papers explored the correlation between 24-h movement and mental health, 8 papers explored changes in the structure of 24-h movement using isochronous substitution models, and 3 explored mediators of 24-h movement affecting mental health. Conclusions: There are few studies on the association between 24-h movement and mental health in adolescents, and the measurement tools used need to be standardized. In the future, isochronous substitution models or real-world intervention studies are needed to find the recommended 24-h movement packages that can maximize the health effects of the movement and are easy to achieve at the same time.

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Background：Transcutaneous carbon dioxide partial pressure (TcPCO2) and transcutaneous oxygen partial pressure (TcPO2) monitoring make it possible to continuously monitor neonatal PCO2/PO2 and reduce the number of blood collections. However, clinicians are very concerned about its safety and accuracy. Objective：To reflect the consistency of TcPCO2/TcPO2 monitoring values and PaCO2/PaO2 monitoring values through a systematic review and meta-analysis. Design：Systematic review and meta-analysis. Methods：A systematic literature retrieval was performed in English databases of Ovid MEDLINE, Ovid Embase and Chinese databases of SinoMed, Wanfang and CNKI. Search strategy was developed using key words of neotate, TcPCO2 and TcPO2. After deduplication, the literature was first screened by reading titles and abstracts by two leading authors independently who then finished the full-text screening. A self-made excel form was used to extract the year of publication, gestational age at birth, gestational age at monitoring, birth weight, weight at monitoring, sample size and the number of monitored pairs, the probe temperature, monitoring site, duration and equipment, blood gas values difference by TcPCO2/TcPO2and PaCO2/PaO2 , correlation coefficient and adverse events. Meta-analysis was performed by Stata 17. Main outcome measures：Difference in blood gas results between TcPCO2/TcPO2and PaCO2/PaO2. Results：A total of 875 articles were retrieved in both Chinese and English. After deduplication, preliminary screening, and full-text screening, 40 articles were included in the analysis, including 14 in Chinese and 26 in English. The summarized differences between TcPCO2 and PaCO2 in probe temperature subgroups of 44℃ vs 43℃, 42℃, 40℃ vs 41℃, and 38℃ vs 39℃ were 2.37(95%CI: 2.17 to 2.67), 2.48(95%CI: 1.17 to 3.79), 4.47(95%CI: 3.03 to 5.92), and 5.96(95%CI: 5.27 to 6.64) respectively, and the Pearson coefficient ranged from 0.78 to 0.89 among the four subgroups. For the deviation from PaCO2, it was 5% in the 43℃ vs 44℃ subgroup, 118% to 14.8% in the 40℃ vs 41℃ subgroups, and 17% in the 38℃ vs 39℃ subgroups. The summarized difference between TcPO2 and PaO2 in probe temperature subgroups of 44℃ vs 43℃, 42℃, 40℃ vs 41℃, and 38℃ vs 39℃ were -7.28(95%CI: -12.92 to -1.63), -5.61(95%CI: -6.61 to -4.62), -28.85(95%CI: -35.12 to -22.58) and -31.42(95%CI: -35.97 to -26.88) respectively, and the Pearson coefficient was 0.35~0.91 among the four subgroups. Eight studies described mild skin redness and no adverse events of skin burns were reported. Conclusion：Without controlling the monitoring site, duration, time point, equipment, and neonatal diseases and conditions, TcPCO2 values are strongly correlated with the PaCO2 values, which is about 7mmHg higher than PaCO2. Under standardized operations, TcPCO2 can replace PaCO2. Within 38℃ to 44℃, the commonly used clinical probe temperature, the higher the probe temperature, the more accurately TcPCO2 can reflect PaCO2, the less skin redness adverse events will occur. Since TcPO2 is weakly related to PaO2, it is not recommended to use TcPO2 to reflect PaO2.

Background It is of great significance to predict the mortality of children with severe infection scientifically and effectively. In the past, the relationship between illness and death in critically ill children was mostly predicted by scores with poor accuracy like the Pancreatitis Complications and Severity Index. Objective To explore the sensitive indicators for the early warning of the death in children with severe infection by machine learning combined with feature screening. Design Cohort study. Methods We conducted the cohort study based on the pediatric Multi-center Infectious Diseases Collaboration Network database of 54 PICUs in 20 provincial administrative regions of China. In total, 122 clinical features of 11 clinical dimensions were collected from children aged > 28 days after birth to 18 years, with confirmed infection and at least one organ dysfunction. A risk prediction model for mortality in critically ill children with infections was established by constructing logistic regression models (LR), random forest models (RF), extreme gradient boosting tree models (XGB), and backpropagation neural network models (BP) through machine learning techniques and screening important clinical features. Main outcome measures AUROC and the performance of the model in screening clinical characteristics. Results From April 1, 2022 to December 31, 2023, there were 1 738 cases of severe infection with complete records at PICU admission, at PICU 24h stay and at discharge from PICU, of whom 1 396 patients survived or improved, and 342(19.6%) died or deteriorated. After data preprocessing by outlier processing, missing value filling, mandatory value interval range testing, normalization processing, 1 738 pieces of information were entered into machine learning to build the model. According to the ration of 4∶1, 1 390 patients were enrolled in training sets and 348 were in validation sets. In training sets, 1 116 patients survived (or cured) and 274 died (or worsened), and in validation sets, 280 patients survived (or cured), and 68 died (or worsened). In training sets, a total of 122 clinical features were input. After machine learning and feature screening, the range of AUROC of LR, RF and XGB was 0.74-0.78 in validation sets after 50 rounds of 5-fold stratified cross-validation. Features with greater importance than the mean value were selected to construct the optimal clinical features in LR, RF, and XGB models. At present, there is no good method to measure the importance of BP characteristics. Clinical features constructed by the LR model were closer to clinical expectations than by RF and XGB. Conclusion Machine learning is less than perfect in predicting death of severe infectious diseases in children, and the clinical futures screened by predictive model are still far from clinical expectations.

Background The number of pediatric patients undergoing prolonged mechanical ventilation (PMV) in pediatric intensive care units (PICUs) has been rapidly increasing, but the factors influencing mortality among these patients remain unclear. Objective To analyze the factors affecting mortality in pediatric patients receiving PMV in PICUs. Design Retrospective cohort study. Methods This study included consecutive cases of invasive mechanical ventilation for ≥14 days with ≥6 hours of ventilation per day at the PICU of the Children's Hospital of Chongqing Medical University from October 1, 2020, to June 30, 2021. Patients were followed for one month after discharge with survival and mortality as outcomes. Data were collected at PICU admission, during PICU treatment, and at discharge. Cox regression analysis was used to explore factors influencing mortality. Main outcome measures Factors influencing mortality in children undergoing PMV. Results During the study period, 1 815 patients were admitted to the PICU with 1 144 requiring mechanical ventilation. One hundred and twenty-seven patients met the inclusion criteria for PMV, among which 99 survived and 28 (22.0%) died during the first month of discharge. A multivariable Cox proportional hazards model was constructed using 10 variables from information at PICU admission, during treatment, and at discharge. The results showed that for risk of death during the first month of discharge, a PELOD-2 score ≥4 during the course was associated with a 2.9-fold increased risk (HR=2.893, 95% CI: 1.182-7.079), blood transfusion therapy with a 2.8-fold increased risk (HR=2.766, 95% CI: 1.012-7.558), blood purification therapy with a 3-fold increased risk (HR=2.978, 95% CI: 1.108-8006), and mechanical ventilation duration ≥30 days with a 3.1-fold increased risk (HR=3.062, 95% CI: 1.282-7.312), while hospital stay length≥35 days was associated with an 89% reduction in the risk of death (HR=0.112, 95% CI: 0.037-7.312). Conclusion The mortality rate among children receiving PMV in the PICU was 22%. Factors such as a PELOD-2 score ≥4, blood transfusion, blood purification therapy, and mechanical ventilation duration ≥30 days were associated with approximately a threefold increase in the risk of death during the first month after discharge, while hospital stay length ≥35 days was associated with a decreased risk of death.