Trends of falls mortality among older adults in urban and rural China, 1987-2021.

BACKGROUND: Falls in older age pose a major public health concern, with unclear urban-rural patterns of falls mortality in China. This study examines the trends of late-life falls mortality in urban and rural China over a 35-year period. METHODS: Falls mortality data were sourced from China's National Health Commission. Joinpoint regression analysis was used to examine changes in trends and age-period-cohort modelling to estimate age, period and cohort effects on fall-related mortality from 1987 to 2021. Net drift, local drift, longitudinal age curves and period relative risks were also calculated. RESULTS: The age-standardised falls mortality in older age showed a long-term trend of initial decline prior to 2003, followed by a steep increase thereafter, with notable distinctions between urban and rural patterns. The rise in rural populations, particularly among older males, was more conspicuous. In rural areas, the decline in falls mortality diminished with age, contrary to the urban trend. Falls mortality increased with age in both urban and rural older populations, peaking in the group aged 85-89. The period effect curves of falls mortality in urban and rural areas both approximated a U-shaped pattern while there were minor variations in early cohorts. CONCLUSIONS: China has experienced a consistent rise in late-life falls mortality in recent years. Notably, there are significant urban-rural disparities in age, period and cohort effects of fall-related mortality among older adults. Rural residents, males and older age groups have potential higher fatal-falls risk. Targeted strategies should be implemented to prevent late-life falls.

The effects of graphene on low-temperature anammox process: The insights from short-term tests and long-term operation.

Effluent quality deterioration caused by seasonal low temperature is a great challenge to the application of anammox technology. Here, the effects of different graphene materials on anammox process were investigated under both optimal temperature and low-temperature. The batch tests showed that at 30 °C, 300 mg/L of reduced graphene oxide­sodium alginate gel (RGOSA) had the most significant promoting effect, reaching nitrogen removal efficiency (NRE) and nitrogen removal rate (NRR) of 95 % and 8.88 mgN/L/d, respectively. The changes of EPS secretion patterns and increasing of key enzymes activity might contribute to the enhanced anammox activity. During the long-term operation of anammox reactor, the NRE and NRR of the reactor decreased when the temperature dropped to 15 °C, showing an NRE of 50 %-57 % with the addition of 200 mg/L of reduced graphene oxide (RGO) and 40 %-45 % with the addition of 20 mg/L of RGO. Furthermore, specific anammox activity (SAA) of the RGO200 reactor at 15 °C increased by 57.1 % compared to the UASB reactor without graphene addition. Additionally, 16S rRNA and metagenomic analysis results revealed anammox bacteria Ca. Kuenenia was the dominant bacteria. Moreover, the RGO can significantly increase the relative abundance of N-converting functional genes. This study demonstrates the graphene materials can help anammox process adapting to low temperatures, providing a possible solution for the application of anammox technology.

Association between chronic disease status and transitions in depressive symptoms among middle-aged and older Chinese population: Insights from a Markov model-based cohort study.

BACKGROUND: The relationship between chronic disease status (CDS) and transitions in depressive symptoms (DS) remains unclear. This study explores the association between CDS and DS transitions. METHODS: This cohort study analyzed data from 8175 participants aged 45+, sourced from China Family Panel Studies (2016, 2018, 2020). DS were assessed using a brief version of Center for Epidemiologic Studies Depression Scale (CES-D). CDS was categorized into healthy, single disease, and multimorbidity. Markov models were used to estimate state transition intensities, mean sojourn times and hazard ratios (HRs). RESULTS: DS transitions occurred between adjacent and non-adjacent states, but transition intensity between adjacent states was higher than among non-adjacent states. Self-transition intensities of severe-DS, mild-DS, and non-DS progressively increased, with average durations of 1.365, 1.482, and 7.854 years, respectively. Both single disease and multimorbidity were significantly associated with an increased risk of transitioning from non-DS to mild-DS, with multimorbidity showing a stronger association. In contrast, HRs for single diseases transitioning from mild-DS to severe-DS were significantly lower than 1. Furthermore, their HRs were almost <1 in recovery transitions but not statistically significant. LIMITATIONS: Specific chronic diseases and their combinations were not analyzed. CONCLUSIONS: The progression of DS exhibits various pathways. CDS is associated with DS transitions, but the roles of single disease and multimorbidity may differ across different DS progression stages. Both conditions were significantly linked to the risk of new-onset DS, with multimorbidity posing a greater association. However, this relationship is not observed in other progression stages. These findings could provide insights for early prevention and intervention for DS.

A Multi-State Model Study of the Disability-Free Life Expectancy Among Older Adults with Chronic Multimorbidity Based on CHARLS - China, 2011-2020.

What is already known about this topic?: Chronic disease multimorbidity is prevalent among older Chinese people, seriously affecting their well-being and quality of life. What is added by this report?: This study estimated the impact of multimorbidity on the risk of health state transitions and health expectancy among older adults in China. It used population-representative, long-term longitudinal data and multi-state Markov modeling along with microsimulation methods. What are the implications for public health practice?: The study results suggest that the Chinese government should strengthen the prevention and management of multimorbidity and accelerate the transition from chronic disease management to multimorbidity management.

Trends and Distribution of Infertility - Asia Pacific Region, 1990-2021.

What is already known about this topic?: Infertility represents a significant global public health concern, impacting approximately 15% of couples of reproductive age worldwide. Despite this, data on infertility prevalence in the demographically diverse Asia-Pacific region remains sparse. What is added by this report?: This study examines the trends and distribution of infertility in the Asia-Pacific region from 1990 to 2021, revealing a significant increase in female infertility. The growth rate of secondary infertility has exceeded that of primary infertility. Additionally, an increase in the prevalence of polycystic ovary syndrome (PCOS) may be a significant contributor. The research also highlights geographical variations in the prevalence and trends of infertility across different countries. What are the implications for public health practice?: The findings emphasize the significance of sexual and reproductive health services and rights in safeguarding fertility.

Feasibility of simultaneous optimization of Anammox start-up and nitrogen removal performance by intermittent dosing of nanoscale zero-valent iron.

The long acclimation period and sensitivity to environmental conditions of Anammox are the bottlenecks for its promotion and application. An innovative strategy was adopted to accelerate functional microbial enhancement and improve nitrogen removal performance by inoculating cryopreserved Anammox sludge and activated sludge with intermittent dosing of nanoscale zero-valent iron (nZVI). The acclimation time was shortened by 76 days with nitrogen removal efficiency (NRE) reaching up to 91.07 %. Anammox, NDFO (nitrate/nitrite-dependent Fe(II) oxidation), Feammox (Fe(III) reduction coupled with anaerobic ammonium oxidation) and abiotic reactions were coupled in the system with nZVI, contributing to 69.79 %, 15.14 %, 9.84 % and 0.25 % of nitrogen removal, respectively. Further microbial analysis demonstrated significant enrichment of functional microorganisms such as Candidatus Jettenia, Acidovorax and Comamonas. High-efficient nitrogen removal was attribute to the increase of functional genes involved in Anammox, electronic transfer, heme C synthesis and iron metabolism. This work provides an inspiring idea for the mainstream Anammox application.

Role of microglia in stress-induced alcohol intake in female and male mice.

Rates of alcohol use disorder (AUD) have escalated in recent years, with a particular increase among women. Women are more susceptible to stress-induced alcohol drinking, and preclinical data suggest that stress can increase alcohol intake in female rodents; however, a comprehensive understanding of sex-specific neurobiological substrates underlying this phenomenon is still emerging. Microglia, the resident macrophages of the brain, are essential for reshaping neuronal processes, and microglial activity contributes to overall neuronal plasticity. We investigated microglial dynamics and morphology in limbic brain structures of male and female mice following exposure to stress, alcohol or both challenges. In a modified paradigm of intermittent binge drinking (repeated "drinking in the dark"), we determined that female, but not male, mice increased their alcohol consumption after exposure to a physical stressor and re-exposure trials in the stress-paired context. Ethanol (EtOH) drinking and stress altered a number of microglial parameters, including overall number, in subregions of the amygdala and hippocampus, with effects that were somewhat more pronounced in female mice. We used the CSF1R antagonist PLX3397 to deplete microglia in female mice to determine whether microglia contribute to stress-induced escalation of EtOH intake. We observed that microglial depletion attenuated stress-induced alcohol intake with no effect in the unstressed group. These findings suggest that microglial activity can contribute to alcohol intake under stressful conditions, and highlight the importance of evaluating sex-specific mechanisms that could result in tailored interventions for AUD in women.

Sensory impairment, loneliness, and the discordance between subjective and objective cognitive function among older adults: A multi-cohort study.

OBJECTIVES: This study aimed to examine the association between sensory impairment and the discordance between subjective/objective cognitive function among older adults and test the mediating effect of loneliness. METHODS: We used data from four cohort studies conducted in 16 countries (N = 19,119). Sensory impairment and subjective cognitive impairment were self-reported. Objective cognitive impairment was measured in three dimensions. Generalized estimating equations were conducted to examine the association between sensory impairment and discordance in subjective/objective cognitive function. Cross-lagged panel model and a bootstrap method with 2,000 samples were employed to verify the mediating effect. RESULTS: Sensory impairment was related to an increased risk of subjective cognitive impairment (OR = 4.70, 95 % CI 4.33-5.10), objective impairment (OR = 1.51, 95 %CI 1.31-1.74), as well as the discordance in subjective/objective cognitive function (OR = 1.35, 95 %CI 1.06-1.71 for older adults with normal subjective cognitive function). In contrast, sensory impairment was associated with a decreased risk of discordant subjective/objective cognitive function among those with subjective cognitive impairment (OR = 0.79, 95 %CI 0.66-0.94). Moreover, loneliness mediated the association between sensory impairment and subjective cognitive impairment (standardized indirect effect = 0.002, 95 %CI 0.001-0.004), objective cognitive impairment (standardized indirect effect = 0.005, 95 %CI 0.003-0.007) as well as the discordance in subjective/objective cognitive function (standardized indirect effect = 0.001, 95 %CI 0.001-0.003 for older adults with normal subjective cognitive function). CONCLUSIONS: Significant association between sensory impairment and discordance in subjective/objective cognitive function and the mediating role of loneliness were revealed, varying by subjective cognitive function. Early screening on sensory impairment and targeted interventions on loneliness should be considered in future policies on cognitive impairment.

What impact does hearing impairment have on cognitive health in older married couples in China?

Hearing impairment is a common geriatric health problem and chronic stressor, and it is associated with poor cognitive outcomes. However, little is known about the impact of hearing impairment in married couples, particularly its potential spillover effects on the cognitive health among spouses of individuals with impairment. Drawing on a stress-proliferation perspective, we used actor-partner interdependence models to examine (1) whether an individual's hearing impairment influences their spouse's cognitive function; and (2) whether AL, symptoms of depression, and social participation serve as mediators for such an association. We utilized data from the 2015 (baseline) and 2018 (3-year follow-up) waves of the China Health and Retirement Longitudinal Study. 4434 couples were included at baseline, and 2190 couples remained after the 3-year follow-up. Hearing impairment among married women was associated with negative impacts on their spouses' cognitive function. Symptoms of depression and social participation may have served as potential mediators in this relationship. For married men, there was no statistically significant association between hearing impairment and spouses' cognitive function. Our findings suggest that hearing impairment among one spouse can lead to negative impacts on the other, but that this effect may depend on gender. Early diagnosis and couple-based interventions for hearing impairment are important for the cognitive health of both hearing-impaired individuals and their spouses.

Relationship between HLA genetic variations, COVID-19 vaccine antibody response, and risk of breakthrough outcomes.

The rapid global distribution of COVID-19 vaccines, with over a billion doses administered, has been unprecedented. However, in comparison to most identified clinical determinants, the implications of individual genetic factors on antibody responses post-COVID-19 vaccination for breakthrough outcomes remain elusive. Here, we conducted a population-based study including 357,806 vaccinated participants with high-resolution HLA genotyping data, and a subset of 175,000 with antibody serology test results. We confirmed prior findings that single nucleotide polymorphisms associated with antibody response are predominantly located in the Major Histocompatibility Complex region, with the expansive HLA-DQB1*06 gene alleles linked to improved antibody responses. However, our results did not support the claim that this mutation alone can significantly reduce COVID-19 risk in the general population. In addition, we discovered and validated six HLA alleles (A*03:01, C*16:01, DQA1*01:02, DQA1*01:01, DRB3*01:01, and DPB1*10:01) that independently influence antibody responses and demonstrated a combined effect across HLA genes on the risk of breakthrough COVID-19 outcomes. Lastly, we estimated that COVID-19 vaccine-induced antibody positivity provides approximately 20% protection against infection and 50% protection against severity. These findings have immediate implications for functional studies on HLA molecules and can inform future personalised vaccination strategies.

Early-life exposure to tobacco, genetic susceptibility, and accelerated biological aging in adulthood.

Early-life tobacco exposure serves as a non-negligible risk factor for aging-related diseases. To understand the underlying mechanisms, we explored the associations of early-life tobacco exposure with accelerated biological aging and further assessed the joint effects of tobacco exposure and genetic susceptibility. Compared with those without in utero exposure, participants with in utero tobacco exposure had an increase in Klemera-Doubal biological age (KDM-BA) and PhenoAge acceleration of 0.26 and 0.49 years, respectively, but a decrease in telomere length of 5.34% among 276,259 participants. We also found significant dose-response associations between the age of smoking initiation and accelerated biological aging. Furthermore, the joint effects revealed that high-polygenic risk score participants with in utero exposure and smoking initiation in childhood had the highest accelerated biological aging. There were interactions between early-life tobacco exposure and age, sex, deprivation, and diet on KDM-BA and PhenoAge acceleration. These findings highlight the importance of reducing early-life tobacco exposure to improve healthy aging.

The long-term changing patterns of suicide mortality in China from 1987 to 2020: continuing urban-rural disparity.

BACKGROUND: Over the past three decades, China has experienced significant changes in urban-rural, gender, and age-specific suicide mortality patterns. This study aimed to investigate the long-term trends in suicide mortality in China from 1987 to 2020. METHODS: Suicide mortality data were obtained from China's National Health Commission. Joinpoint regression analysis was used to examine changes in trends and age-period-cohort modeling to estimate age, period, and cohort effects on suicide mortality from 1987 to 2020. Net drift, local drift, longitudinal age curves, and period relative risks were also calculated. RESULTS: Crude and age-standardized suicide mortality in China showed continuing downward trends from 1987 to 2020, with a more pronounced decrease in rural areas (net drift = -7.07%, p<0.01) compared to urban areas (net drift = -3.41%, p<0.01). The decline curve of urban areas could be divided into three substages. Period and cohort effects were more prominent in rural areas. Suicide risk was highest among individuals aged 20-24 and gradually increased after age 60. Females, particularly those of childbearing age, had higher suicide risk than males, with a reversal observed after age 50. This gender reversal showed distinct patterns in urban and rural areas, with a widening gap in urban areas and a relatively stable gap in rural areas. CONCLUSIONS: Suicide mortality in China has consistently declined over the past three decades. However, disparities in age, gender, and urban-rural settings persist, with new patterns emerging. Targeted suicide prevention programs are urgently needed for high-risk groups, including females of childbearing age and the elderly, and to address the slower decrease and reversing urban-rural gender trends.

Biased virus transmission following sequential coinfection of Aedes aegypti with dengue and Zika viruses.

BACKGROUND: Mosquito-borne arboviruses are expanding their territory and elevating their infection prevalence due to the rapid climate change, urbanization, and increased international travel and global trade. Various significant arboviruses, including the dengue virus, Zika virus, Chikungunya virus, and yellow fever virus, are all reliant on the same primary vector, Aedes aegypti. Consequently, the occurrence of arbovirus coinfection in mosquitoes is anticipated. Arbovirus coinfection in mosquitoes has two patterns: simultaneous and sequential. Numerous studies have demonstrated that simultaneous coinfection of arboviruses in mosquitoes is unlikely to exert mutual developmental influence on these viruses. However, the viruses' interplay within a mosquito after the sequential coinfection seems intricated and not well understood. METHODOLOGY/PRINCIPAL FINDINGS: We conducted experiments aimed at examining the phenomenon of arbovirus sequential coinfection in both mosquito cell line (C6/36) and A. aegypti, specifically focusing on dengue virus (DENV, serotype 2) and Zika virus (ZIKV). We firstly observed that DENV and ZIKV can sequentially infect mosquito C6/36 cell line, but the replication level of the subsequently infected ZIKV was significantly suppressed. Similarly, A. aegypti mosquitoes can be sequentially coinfected by these two arboviruses, regardless of the order of virus exposure. However, the replication, dissemination, and the transmission potential of the secondary virus were significantly inhibited. We preliminarily explored the underlying mechanisms, revealing that arbovirus-infected mosquitoes exhibited activated innate immunity, disrupted lipid metabolism, and enhanced RNAi pathway, leading to reduced susceptibility to the secondary arbovirus infections. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that, in contrast to simultaneous arbovirus coinfection in mosquitoes that can promote the transmission and co-circulation of these viruses, sequential coinfection appears to have limited influence on arbovirus transmission dynamics. However, it is important to note that more experimental investigations are needed to refine and expand upon this conclusion.

Perceptions of Community Corrections and Treatment Experience: A Qualitative Study Among People With Incarceration Histories Receiving Outpatient Methadone Treatment.

BACKGROUND: Community correctional experiences among individuals receiving methadone treatment (MT) for opioid use disorder (OUD) are poorly understood. We qualitatively investigated perceptions of community corrections and treatment experiences among individuals with criminal-legal system experience currently receiving outpatient MT. METHODS: From January to December 2017, we recruited 42 individuals with history of criminal-legal system involvement enrolled in outpatient MT at a low-barrier nonprofit organization operating multiple clinics in Connecticut. An experienced qualitative research team conducted one-to-one, in-person, semistructured interviews about incarceration and treatment experiences with individuals receiving MT. Participants completed a demographics survey. The interviews were audiorecorded, transcribed, de-identified, and independently coded using NVivo. RESULTS: Participants described the community corrections system as restrictive and abstinence-focused. Most participants described positive perceptions of and experiences with community corrections officers (CCOs), yet described negative perceptions of and experiences with the community corrections system overall. Participants perceived CCOs to have limited knowledge of OUD and MT. Participants described a range of CCO judgment toward their OUD, with some appearing understanding and nonjudgmental while others were perceived to have stigma and prejudice. Few participants noted assistance from CCOs with seeking MT or community-based substance use disorder care. Some participants desired improved treatment facilitation, but viewed forced or coercive treatment negatively. CONCLUSION: To our knowledge, this is the first qualitative study to examine community corrections experience among people receiving outpatient medication for OUD. While individuals receiving MT have negative experiences with the community corrections system, they perceive individual CCOs positively. Interventions addressing gaps in CCOs knowledge of OUD and MT are needed to optimize support for individuals on probation or parole with OUD. Provision of OUD treatment facilitation appears desirable to some individuals in community supervision.

The trends of mental disorders mortality in China over a 33-year period.

OBJECTIVES: We investigated the variations in the trends of mental disorders mortality by age, period, and cohort, over a 33-year period from 1987 to 2020, to reveal the relationship between age, period, cohort, and mental disorders mortality, as well as providing guidance for resource allocation to prevent mental disorders-related deaths in vulnerable target populations. METHODS: The data of mental disorders mortality 1987-2020 were from five administrative organizations, which collected from the National Health Commission in China with national monitoring by sex and age, covering 31 provinces in China. The International Classification of Diseases (ICD), its 9th Revision (ICD-9) and its 10th Revision were used to code the mental diseases. From 1987-2002, ICD-9 was used, and ICD-10 was used from 2003 to 2020. The age standardized mortality rates (ASMRs) were calculated using the World Standard Population as the reference. We used joinpoint models to assess the trends of mental disorders mortality in China for the period 1987-2020. And the age-period-cohort models were employed to estimate the age-period-cohort effect on mental disorders mortality. RESULTS: The age-standardized overall mental disorders mortality rate (ASMR) showed a downward trend from 1987 to 2020. Further, the ASMR of individuals in urban was higher than that in rural from 1987 to 2001, but, post-2002, this urban-rural disparity in ASMR showed a less clear pattern, with urban areas occasionally surpassing rural areas and vice versa. ASMR is less prevalent among females compared to males overall. The contribution of age effects to mental disorders mortality gradually increases with advancing age, the period effects of mental disorders mortality gradually decrease over time. The cohort effect's contribution to mental disorders mortality decreases in the newly born population, while in the older birth cohorts, the cohort effect's contribution to the mortality rate of mental disorders increases. CONCLUSIONS: The ASMR exhibits a decreasing trend from 1987 to 2020, and these change trend showed urban-rural and sex differences. The primary factors contributing to this overall decline are period effects and cohort effects. Our results provide valuable information for shaping mental health policies, designing targeted interventions, and preparing for future changes in disease mortality rates. The focus on different demographic factors allows for a nuanced and tailored approach to mental health promotion and intervention strategies.

Mating harassment may boost the effectiveness of the sterile insect technique for Aedes mosquitoes.

The sterile insect technique is based on the overflooding of a target population with released sterile males inducing sterility in the wild female population. It has proven to be effective against several insect pest species of agricultural and veterinary importance and is under development for Aedes mosquitoes. Here, we show that the release of sterile males at high sterile male to wild female ratios may also impact the target female population through mating harassment. Under laboratory conditions, male to female ratios above 50 to 1 reduce the longevity of female Aedes mosquitoes by reducing their feeding success. Under controlled conditions, blood uptake of females from an artificial host or from a mouse and biting rates on humans are also reduced. Finally, in a field trial conducted in a 1.17 ha area in China, the female biting rate is reduced by 80%, concurrent to a reduction of female mosquito density of 40% due to the swarming of males around humans attempting to mate with the female mosquitoes. This suggests that the sterile insect technique does not only suppress mosquito vector populations through the induction of sterility, but may also reduce disease transmission due to increased female mortality and lower host contact.

Individual-level socioeconomic status and cataract-induced visual disability among older adults in China: the overview and urban-rural difference.

Objective: To investigate the prevalence of cataract-induced visual disability and its association with individual-level socioeconomic status (SES) among older adults in China. Methods: Using the data of 354,743 older adults (60 years and older) from the Second China National Sample Survey on Disability in 2006. Cross-sectional study design was applied. The differences in visual disability prevalence of cataracts among sociodemographic subgroups were analyzed by the chi-square test, and the association between individual-level SES and cataract-induced visual disability was investigated by the multivariate logistic regression model. Results: The weighted visual disability prevalence of cataracts was 4.84% in 2006. Older people with a higher household income per capita (OR = 0.83, 95% CI: 0.81-0.85), higher education level (primary school vs. illiteracy: OR = 0.80, 95% CI: 0.76-0.83; ≥undergraduate college vs. illiteracy: OR = 0.31, 95% CI: 0.25-0.39), and occupation (OR = 0.53, 95% CI: 0.50-0.56) were less likely to suffer from cataract-induced visual disability. Household income per capita and education level increase played a greater role in decreasing the risk of visual disability caused by cataracts in urban areas, while having occupation contributed more to reducing the risk of disability in rural areas. Conclusion: The gap in individual-level SES is closely related to the visual health inequities among older Chinese people and there are two distinct mechanisms in rural and urban areas. Strategies to promote collaborative healthcare development regionally, strengthen safeguards for disadvantaged groups, and increase public awareness of visual disability prevention are warranted.

Socioeconomic disparities in education placement for children of primary school age with autism spectrum disorder in China.

Relatively little is known about education placements for children with autism spectrum disorder (ASD) in China. While disparities in ASD diagnoses and services for the population broadly are often documented, the presence and determinants of differences in the educational placement of ASD children are less studied and understood. By identifying who is likely to be in segregated settings, we can discern how to best support them and facilitate a possible transition to a less restrictive setting. This study describes four placements (regular schools, special schools, institutions, homes) and their influencing factors retrospectively in a large sample (n = 2,190) of Chinese primary school-aged children (6-12 years old). We divided ASD into severe and mild to moderate categories for analysis. Children with ASD were more likely to study in a regular school (48.60%), while 13.88% were in a special school. Children with severe ASD were placed in less regular settings than children with mild to moderate ASD. However, families with higher socioeconomic status (SES) were more likely to place their children in regular schools than lower SES families if their children experienced mild to moderate symptoms. Children with severe ASD were more likely to be placed in expensive institutions for families with higher SES than those with lower SES. SES disparities in educational placement existed and had two manifestations. It is important to characterize educational placements of students with ASD to determine the extent to which they are placed in general education settings, which are often the preferred placement.

scEM: A New Ensemble Framework for Predicting Cell Type Composition Based on scRNA-Seq Data.

With the advent of single-cell RNA sequencing (scRNA-seq) technology, many scRNA-seq data have become available, providing an unprecedented opportunity to explore cellular composition and heterogeneity. Recently, many computational algorithms for predicting cell type composition have been developed, and these methods are typically evaluated on different datasets and performance metrics using diverse techniques. Consequently, the lack of comprehensive and standardized comparative analysis makes it difficult to gain a clear understanding of the strengths and weaknesses of these methods. To address this gap, we reviewed 20 cutting-edge unsupervised cell type identification methods and evaluated these methods comprehensively using 24 real scRNA-seq datasets of varying scales. In addition, we proposed a new ensemble cell-type identification method, named scEM, which learns the consensus similarity matrix by applying the entropy weight method to the four representative methods are selected. The Louvain algorithm is adopted to obtain the final classification of individual cells based on the consensus matrix. Extensive evaluation and comparison with 11 other similarity-based methods under real scRNA-seq datasets demonstrate that the newly developed ensemble algorithm scEM is effective in predicting cellular type composition.