Silencing of ceramide synthase 2 in hepatocytes modulates plasma ceramide biomarkers predictive of cardiovascular death.

Emerging clinical data show that three ceramide molecules, Cer d18:1/16:0, Cer d18:1/24:1, and Cer d18:1/24:0, are biomarkers of a fatal outcome in patients with cardiovascular disease. This finding raises basic questions about their metabolic origin, their contribution to disease pathogenesis, and the utility of targeting the underlying enzymatic machinery for treatment of cardiometabolic disorders. Here, we outline the development of a potent N-acetylgalactosamine-conjugated antisense oligonucleotide engineered to silence ceramide synthase 2 specifically in hepatocytes in vivo. We demonstrate that this compound reduces the ceramide synthase 2 mRNA level and that this translates into efficient lowering of protein expression and activity as well as Cer d18:1/24:1 and Cer d18:1/24:0 levels in liver. Intriguingly, we discover that the hepatocyte-specific antisense oligonucleotide also triggers a parallel modulation of blood plasma ceramides, revealing that the biomarkers predictive of cardiovascular death are governed by ceramide biosynthesis in hepatocytes. Our work showcases a generic therapeutic framework for targeting components of the ceramide enzymatic machinery to disentangle their roles in disease causality and to explore their utility for treatment of cardiometabolic disorders.

Retrotransposition and Crystal Structure of an Alu RNP in the Ribosome-Stalling Conformation.

The Alu element is the most successful human genomic parasite affecting development and causing disease. It originated as a retrotransposon during early primate evolution of the gene encoding the signal recognition particle (SRP) RNA. We defined a minimal Alu RNA sufficient for effective retrotransposition and determined a high-resolution structure of its complex with the SRP9/14 proteins. The RNA adopts a compact, closed conformation that matches the envelope of the SRP Alu domain in the ribosomal translation elongation factor-binding site. Conserved structural elements in SRP RNAs support an ancient function of the closed conformation that predates SRP9/14. Structure-based mutagenesis shows that retrotransposition requires the closed conformation of the Alu ribonucleoprotein particle and is consistent with the recognition of stalled ribosomes. We propose that ribosome stalling is a common cause for the cis-preference of the mammalian L1 retrotransposon and for the efficiency of the Alu RNA in hijacking nascent L1 reverse transcriptase.

ProteinTools: a toolkit to analyze protein structures.

The experimental characterization and computational prediction of protein structures has become increasingly rapid and precise. However, the analysis of protein structures often requires researchers to use several software packages or web servers, which complicates matters. To provide long-established structural analyses in a modern, easy-to-use interface, we implemented ProteinTools, a web server toolkit for protein structure analysis. ProteinTools gathers four applications so far, namely the identification of hydrophobic clusters, hydrogen bond networks, salt bridges, and contact maps. In all cases, the input data is a PDB identifier or an uploaded structure, whereas the output is an interactive dynamic web interface. Thanks to the modular nature of ProteinTools, the addition of new applications will become an easy task. Given the current need to have these tools in a single, fast, and interpretable interface, we believe that ProteinTools will become an essential toolkit for the wider protein research community. The web server is available at https://proteintools.uni-bayreuth.de.

Family predictors of physical activity change during the COVID-19 lockdown in preschool children in Germany.

The COVID-19 pandemic is associated with crucial changes in children's daily life including their physical activity (PA) and screen time (ST). Among preschool children, the family represents an important factor for sufficient PA levels by being the gatekeeper for PA. Thus, the aim of this study was to investigate the influence of the family environment, specifically SES, parental support, and having siblings on COVID-19-related changes of PA and ST behavior in 317 (170 boys, 147 girls) German preschool children using longitudinal data. Our results indicate a decline in total amount of sports-related PA, an increase in outdoor play, as well as an increase in leisure ST in preschool children. The changes in total amount of PA differed between children with different levels of parental support as well as in dependence on having siblings. Furthermore, levels of outdoor play and ST in preschool children were influenced by environmental factors like having access to their own garden. We conclude that the family environment (parental support as well as physical environment) is highly relevant for PA and ST levels in preschool children. To provide every child with PA opportunities during potential future lockdowns, restriction policies should be adapted and parents need sophisticated information about the importance of their support and thus the PA levels of their children.

Prevalence and patient-rated relevance of complexity factors in medication regimens of community-dwelling patients with polypharmacy.

PURPOSE: To describe the prevalence of complexity factors in the medication regimens of community-dwelling patients with more than five drugs and to evaluate the relevance of these factors for individual patients. METHODS: Data were derived from the HIOPP-6 trial, a controlled study conducted in 9 general practices which evaluated an electronic tool to detect and reduce complexity of drug treatment. The prevalence of complexity factors was based on the results of the automated analysis of 139 patients' medication data. The relevance assessment was based on the patients' rating of each factor in an interview (48 patients included for analysis). RESULTS: A median of 5 (range 0-21) complexity factors per medication regimen were detected and at least one factor was observed in 131 of 139 patients. Almost half of these patients found no complexity factor in their medication regimen relevant. CONCLUSION: In most medication regimens, complexity factors could be identified automatically, yet less than 15% of factors were indeed relevant for patients as judged by themselves. When assessing complexity of medication regimens, one should especially consider factors that are both particularly frequent and often challenging for patients, such as use of inhalers or tablet splitting. TRIAL REGISTRATION: The HIOPP-6 trial was registered retrospectively on May 17, 2021, in the German Clinical Trials register under DRKS-ID DRKS00025257.

Community networks of sport and physical activity promotion: an analysis of structural properties and conditions of cooperation.

BACKGROUND: The importance of intersectoral cooperation networks among community organizations located in people's immediate environments in addressing population health problems such as physical inactivity has come into focus in recent years. To date, there is limited evidence on how and why such networks emerge. Therefore, the aims of this study were (a) to analyze the structural properties and (b) to identify the conditions of cooperation in interorganizational community networks of sport and physical activity promotion. METHODS: Survey data on cooperative relationships and organizational attributes of sports and physical activity providers as well as sports administrating organizations in two community networks located in urban districts in southern Germany were collected (Network I: n = 133 organizations; Network II: n = 50 organizations). Two quantitative descriptive procedures - network analysis and stochastic analyses of network modeling (exponential random graphs) - were applied. RESULTS: Similar structures and conditions of cooperation were found in the networks (e.g. low density, centralization). The community sports administrations had the most central positions in both networks. Exponential random graph modeling showed that cooperation took place more frequently in triangular structures (closure effect) and revolved around a few central actors (preferential attachment effect). Organizations from different sectors cooperated more often than organizations from the same sector (heterophily effect). CONCLUSION: The study provided valid and robust findings on significant mechanisms and conditions of interorganizational cooperation in community networks focused on sport and physical activity promotion. Based on the results, implications for the development and most efficient governance of these networks can be derived.

Are Physical Activity, Screen Time, and Mental Health Related During Childhood, Preadolescence, and Adolescence? 11-Year Results From the German Motorik-Modul Longitudinal Study.

Mental health (MH) and behavioral health are fundamental to a good quality of life. Only a few studies have investigated the association between behavioral health (e.g., physical activity (PA), screen time (ST)) and MH from childhood to adolescence. Therefore, we investigated the relationships of PA and ST with MH by sex in an 11-year longitudinal cohort study of German schoolchildren during 2003-2017. A subsample (n = 686; 55.2% female) of participants from the German Motorik-Modul (MoMo) Longitudinal Study who participated in all 3 measurement phases (mean ages: time 1 (baseline; 2003-2006), 5.57 (standard deviation (SD), 1.00) years; time 2 (wave 1; 2009-2012), 11.85 (SD, 1.03) years; time 3 (wave 2; 2014-2017), 16.86 (SD, 1.04) years) were analyzed with regard to PA, ST, and MH (emotional symptoms, conduct problems, hyperactivity/inattention, peer relationship problems, prosocial behavior, and overall strengths and difficulties). Path panel prediction models were fitted with time 1, time 2, and time 3 PA, ST, and MH indicators. PA predicted less television (TV)/video watching in females, and TV/video watching predicted personal computer (PC)/Internet use in both sexes. Behavior and MH results suggested that, for females, higher TV/video watching and PC/Internet use was related to higher MH challenges over the course of maturation. Some preadolescent males' MH challenges increased ST (TV/video watching and PC/Internet use) in adolescence. Researchers should explore innovative and effective methods for reducing childhood ST, especially among females with early signs of MH issues, and addressing preadolescent males' MH challenges.

The relationship of self-reported and device-based measures of physical activity and health-related quality of life in adolescents.

BACKGROUND: Physical activity (PA) has beneficial effects on health and health-related quality of life (HRQoL), which is a protective factor of illness and mortality. The purpose of this examination was to investigate if self-reported and device-based measures of PA were related to HRQoL in adolescents. METHODS: Participants (N = 1565; 54.3% female; Mage = 14.37 years, SDage = 1.99) were recruited from 167 sample points across Germany. Adolescents self-reported their PA, supplemented by a 1-week examination of device-based PA using accelerometry. Additionally, they completed the multidimensional KIDSCREEN-27 to assess HRQoL. RESULTS: Results showed that self-reported PA was correlated with overall HRQoL, Physical Well-Being, Psychological Well-Being, Social Support & Peers, and School Environment, whereas device-based PA was only correlated with Physical as well as Psychological Well-Being. Further, self-reported PA significantly predicted all facets of HRQoL except for Autonomy and Parent Relations, whereas device-based PA solely heightened the amount of explained variance in the Physical Well-Being subscale. CONCLUSIONS: Findings demonstrate the importance of self-reported PA as it is related to almost all facets of HRQoL. Both measures of PA are not congruent in their relationship with HRQoL and thus implications have to be carefully considered. Future studies should investigate the direct effect of PA on HRQoL and health in a longitudinal approach to account for the causality of effects.

Relating outdoor play to sedentary behavior and physical activity in youth - results from a cohort study.

BACKGROUND: Outdoor play, sedentary behavior (SB), and moderate-to-vigorous physical activity (MVPA) are related to youth's health, however, there are research gaps regarding 1) associations between outdoor play, SB, and MVPA across a broad pediatric age range (6-17 years), and 2) longitudinal associations between outdoor play, SB, and MVPA across childhood and adolescence. Two studies were conducted to address those research gaps: Study 1 aimed to investigate relationships between outdoor play and accelerometer-assessed SB and MVPA in a cross-sectional nationwide sample of children and adolescents in Germany. Study 2 aimed to investigate prospective associations between outdoor play and self-reported screen-time SB and MVPA and in a sample of children with three measurement timepoints across 11 years. METHODS: Data were obtained of the German national representative Motorik-Modul (MoMo) Study and the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). In Study 1, N = 2278 participants (6-17 years) were included with self-reported outdoor play and accelerometer-assessed SB and MVPA. Associations were examined via multiple linear regressions. In Study 2, N = 570 participants (baseline: 4-7 years) were included in the longitudinal analysis with follow-ups six and 11 years later. Screen-time SB (TV watching and PC/Gaming), MVPA, and outdoor play were self-reported. Associations were investigated through a path prediction model. RESULTS: Study 1 showed that compared to <1 h outdoor play, higher engagement in daily outdoor play was related to lower SB (1-2 h: - 9.75 min/day, P = 0.017; ≥2 h: - 17.78 min/day, P < 0.001) and higher MVPA (≥2 h: + 3.87 min/day, P = 0.001). The cross-sectional relationship between MVPA and outdoor play was moderated by sex (in favor of males) and age (in favor of younger children). Study 2 showed that outdoor play in early childhood negatively predicted PC use/Gaming in later childhood, but was unrelated to MVPA. CONCLUSION: In Study 1, outdoor play was negatively related to SB cross-sectionally. In Study 2, outdoor play in early childhood was negatively related to PC and Gaming time in later childhood. Thus, providing outdoor play opportunities, especially during early childhood, has potential to prevent SB. Future research should investigate longitudinal relationships using device-based assessments for SB and MVPA.

Comparison of self-reported & device-based, measured physical activity among children in Germany.

BACKGROUND: As children show a more complex but less structured movement behavior than adults, assessment of their many spontaneous and impulsive movements is a challenge for physical activity (PA) assessment. Since neither questionnaires nor accelerometers enable optimal detection of all facets of PA, a multimodal, combined approach of self-reported and device-based methods is recommended. Based on the number of days on which the participants reached the physical activity (PA) values given in the WHO guideline, this study examines 1) the difference between self-reported and device-based, measured PA and 2) whether PA differences between age and gender groups obtained by two methods are comparable. METHODS: Participants aged 6-17 years were randomly chosen and data were collected representatively at 167 sample points throughout Germany within the Motorik-Modul Study. PA of n = 2694 participants (52.3% female) was measured using the ActiGraph accelerometer (ACC) and a physical activity questionnaire (PAQ). The sample was divided into three age groups (6-10 yrs. n = 788, 11-13 yrs. n = 823, 14-17 yrs. n = 1083). Numbers of days per week with at least 60 min moderate to vigorous PA (MVPA) were analyzed for both methods. RESULTS: Only every 25th respondent (4%) reaches the WHO standard of 60 min MVPA every day if measured with ACC. Self-reported PA was slightly higher (9%) (meanPAQ = 3.82 days; meanACC = 2.34 days; Fmethod = 915.85; p = <.001; fCohen = .64). The differences between the methods are significantly smaller in younger children than in the older age groups (Fage = 264.2, p < .001; fCohen = .48). The older the subjects are, the lower is the proportion of those who meet the WHO guideline on each day, with girls meeting the guideline less frequently than boys in all age groups. CONCLUSION: Children and adolescents living in Germany show a very low adherence to the WHO guideline on PA. While younger children are much more active with their free play, especially children over 10 years of age and especially girls should be the target of programs to increase PA.

Trends in active commuting to school from 2003 to 2017 among children and adolescents from Germany: the MoMo Study.

BACKGROUND: Inactivity in children and adolescents is a global issue requiring interventions that target different domains of physical activity, such as active transport. The aim of this study was to assess the prevalence, historical trends and socio-demographic correlates of active commuting to school (ACS) in a nationwide sample of girls and boys from Germany. METHODS: Data of commuting behaviour and socio-demographic factors were collected, covering three measurement points from 2003 to 2017. The MoMo Study derived its data from a representative sample of children and adolescents aged 4-17 years who answered a questionnaire (N = 11 387). Statistically significant differences between Baseline, Wave 1 and Wave 2 were determined via 95% confidence intervals (CIs) for complex samples. RESULTS: Overall, ACS decreased from 84.4% at the first measurement point to 78.3% in the third measurement point. The proportion of cases in which children opted for passive modes of commuting increased predominantly in those aged 4-5 years, in children with a low-to-medium socio-economic status, and in children residing in small- or medium-sized towns. No gender differences were found in active commuting. The results of multinomial logistic regression identified age, migration background and residential area as correlates of walking for boys. For girls, the likelihood of walking, cycling and taking public transport instead of opting for motorized transport increased with age. CONCLUSIONS: Intervention programmes to increase active transport in children and adolescents should target different age groups and also consider parental influence in determining the child's choice of transport mode.

How to disseminate national recommendations for physical activity: a qualitative analysis of critical change agents in Germany.

BACKGROUND: Physical activity recommendations are reached by only a small part of the population. A common problem is that research findings on public health-related topics such as physical activity promotion are oftentimes not translated into practice. The involvement of relevant stakeholders, such as change agents (role models, decision-makers, and/or knowledge mediators), is a common strategy to implement physical activity recommendations in specific settings, as they have the necessary knowledge of contextual factors. However, dissemination and implementation of physical activity recommendations are often prevented by focusing exclusively on the health sector and by underestimating the individual perceptions and needs of change agents. Therefore, the purpose of this study was to address the problem of how physical activity recommendations can be translated into practice through comprehensive consideration of the situation and context of change agents from various sectors of society at different administrative levels. This allows for deriving recommendations for action on how a national dissemination strategy of physical activity recommendations should be designed. METHODS: Qualitative expert interviews were conducted with change agents from different sectors of society and administrative levels in Germany (N = 21). Case selection took place via a sampling plan. The interviews were recorded, transcribed verbatim, and analysed by two trained researchers using qualitative content analysis. RESULTS: The change agents' perceived relevance of physical activity and physical activity promotion and their knowledge of physical activity recommendations varied across different sectors. Nine themes were identified covering the change agents' needs for the implementation of physical activity recommendations: strengthening of political will and cooperation, availability of public space for physical activity, change in awareness and health education, professional qualification, financial incentives, development of physical activity-promoting programmes and structures, provision of resources, bridging the theory-practice gap, and knowledge of physical activity recommendations. CONCLUSIONS: This exploratory study contributes to the development of an evidence-based dissemination strategy of physical activity recommendations involving change agents from various sectors. Cross-sectoral needs and obstacles were identified indicating gaps that have to be addressed. Future research should choose practice-oriented approaches to develop dissemination strategies that are adapted to the needs of local contexts.

Individual factors increasing complexity of drug treatment-a narrative review.

PURPOSE: Complexity of drug treatment is known to be a risk factor for administration errors and nonadherence promoting higher healthcare costs, hospital admissions and increased mortality. Number of drugs and dose frequency are parameters often used to assess complexity related to the medication regimen. However, factors resulting from complex processes of care or arising from patient characteristics are only sporadically analyzed. Hence, the objective of this review is to give a comprehensive overview of relevant, patient-centered factors influencing complexity of drug treatment. METHODS: A purposeful literature search was performed in MEDLINE to identify potential complexity factors relating to the prescribed drug (i.e. dosage forms or other product characteristics), the specific medication regimen (i.e. dosage schemes or additional instructions), specific patient characteristics and process characteristics. Factors were included if they were associated to administration errors, nonadherence and related adverse drug events detected in community dwelling adult patients. RESULTS: Ninety-one influencing factors were identified: fourteen in "dosage forms", five in "product characteristics", twelve in "dosage schemes", nine in "additional instructions", thirty-one in "patient characteristics" and twenty in "process characteristics". CONCLUSIONS: Although the findings are limited by the non-systematic search process and the heterogeneous results, the search shows the influence of many factors on the complexity of drug treatment. However, to evaluate their relevance for individual patients, prospective studies are necessary.

Development of an algorithm to detect and reduce complexity of drug treatment and its technical realisation.

BACKGROUND: The increasing complexity of current drug therapies jeopardizes patient adherence. While individual needs to simplify a medication regimen vary from patient to patient, a straightforward approach to integrate the patients' perspective into decision making for complexity reduction is still lacking. We therefore aimed to develop an electronic, algorithm-based tool that analyses complexity of drug treatment and supports the assessment and consideration of patient preferences and needs regarding the reduction of complexity of drug treatment. METHODS: Complexity factors were selected based on literature and expert rating and specified for integration in the automated assessment. Subsequently, distinct key questions were phrased and allocated to each complexity factor to guide conversation with the patient and personalize the results of the automated assessment. Furthermore, each complexity factor was complemented with a potential optimisation measure to facilitate drug treatment (e.g. a patient leaflet). Complexity factors, key questions, and optimisation strategies were technically realized as tablet computer-based application, tested, and adapted iteratively until no further technical or content-related errors occurred. RESULTS: In total, 61 complexity factors referring to the dosage form, the dosage scheme, additional instructions, the patient, the product, and the process were considered relevant for inclusion in the tool; 38 of them allowed for automated detection. In total, 52 complexity factors were complemented with at least one key question for preference assessment and at least one optimisation measure. These measures included 29 recommendations for action for the health care provider (e.g. to suggest a dosage aid), 27 training videos, 44 patient leaflets, and 5 algorithms to select and suggest alternative drugs. CONCLUSIONS: Both the set-up of an algorithm and its technical realisation as computer-based app was successful. The electronic tool covers a wide range of different factors that potentially increase the complexity of drug treatment. For the majority of factors, simple key questions could be phrased to include the patients' perspective, and, even more important, for each complexity factor, specific measures to mitigate or reduce complexity could be defined.

Comprehensive analysis of high-throughput screens with HiTSeekR.

High-throughput screening (HTS) is an indispensable tool for drug (target) discovery that currently lacks user-friendly software tools for the robust identification of putative hits from HTS experiments and for the interpretation of these findings in the context of systems biology. We developed HiTSeekR as a one-stop solution for chemical compound screens, siRNA knock-down and CRISPR/Cas9 knock-out screens, as well as microRNA inhibitor and -mimics screens. We chose three use cases that demonstrate the potential of HiTSeekR to fully exploit HTS screening data in quite heterogeneous contexts to generate novel hypotheses for follow-up experiments: (i) a genome-wide RNAi screen to uncover modulators of TNFα, (ii) a combined siRNA and miRNA mimics screen on vorinostat resistance and (iii) a small compound screen on KRAS synthetic lethality. HiTSeekR is publicly available at http://hitseekr.compbio.sdu.dk It is the first approach to close the gap between raw data processing, network enrichment and wet lab target generation for various HTS screen types.

Correction to: Tracking physical activity in different settings from late childhood to early adulthood in Germany: the MoMo longitudinal study.

CORRECTION: After publication of the article [1], it has been brought to our attention that the values cited under "indices t1-t0" have been reversed and should be displayed in the opposite order. The corrected Table 1 would appear as follows.

[Simplifying complex drug therapies : Challenges and solutions]. / Komplexe Arzneimitteltherapien vereinfachen : Herausforderungen und Lösungsansätze.

The difficulties of managing a complex medication regimen are often underestimated in outpatient care. A large number of drugs (polypharmacy) and complicated dosage schemes or dosage forms may overstrain patients. Indeed, wrong drug administration can impair treatment success or cause adverse drug events.Patients are often unaware of the medication administration errors. Furthermore they do not voice administration problems, often because they are not aware of the potential to optimize their drug therapy. Medication regimen complexity can often be reduced by simple measures. However, feasible concepts for reducing medication regimen complexity in a structured way have been lacking in routine care so far.Electronic decision support facilitates systematic and efficient identification of factors that increase the complexity of a medication regimen. Furthermore, electronic decision aids may enable physicians and pharmacists to take appropriate measures in order to reduce medication regimen complexity. Personalizing the analysis and resulting measures to reduce medication regimen complexity might increase readiness of patients to implement changes in treatment and, thus, probably increase adherence. The first results of a prospective trial that is supported by the Federal Joint Committee (G-BA) Innovationsfonds (HIOPP-6, Komplexitätsreduktion in der Polypharmazie unter Beachtung von Patientenpräferenzen) will be available in autumn 2018 and answer these questions.

Shift of microRNA profile upon glioma cell migration using patient-derived spheroids and serum-free conditions.

Glioblastoma multiforme (GBM) is the most frequent malignant primary brain tumor. A major reason for the overall median survival being only 14.6 months is migrating tumor cells left behind after surgery. Another major reason is tumor cells having a so-called cancer stem cell phenotype being therefore resistant towards traditional chemo- and radiotherapy. A group of novel molecular targets are microRNAs (miRNAs). MiRNAs are small non-coding RNAs exerting post-transcriptional regulation of gene expression. The aim of this study was to identify differentially expressed miRNAs in migrating GBM cells using serum-free stem cell conditions. We used patient-derived GBM spheroid cultures for a novel serum-free migration assay. MiRNA expression of migrating tumor cells isolated at maximum migration speed was compared with corresponding spheroids using an OpenArray Real-Time PCR System. The miRNA profiling revealed 30 miRNAs to be differentially expressed. In total 13 miRNAs were upregulated and 17 downregulated in migrating cells compared to corresponding spheroids. The three most deregulated miRNAs, miR-1227 (up-regulated), miR-32 (down-regulated) and miR-222 (down-regulated), were experimentally overexpressed. A non-significantly increased migration rate was observed after miR-1227 overexpression. A significantly reduced migration rate was observed after miR-32 and miR-222 overexpression. In conclusion a shift in microRNA profile upon glioma cell migration was identified using an assay avoiding serum-induced migration. Both the miRNA profiling and the functional validation suggested that miR-1227 may be associated with increased migration and miR-32 and miR-222 with decreased migration. These miRNAs may represent potential novel targets in migrating glioma cells.

Longitudinal drop-out and weighting against its bias.

BACKGROUND: The bias caused by drop-out is an important factor in large population-based epidemiological studies. Many studies account for it by weighting their longitudinal data, but to date there is no detailed final approach for how to conduct these weights. METHODS: In this study we describe the observed longitudinal bias and a three-step longitudinal weighting approach used for the longitudinal data in the MoMo baseline (N = 4528, 4-17 years) and wave 1 study with 2807 (62%) participants between 2003 and 2012. RESULTS: The most meaningful drop-out predictors were socioeconomic status of the household, socioeconomic characteristics of the mother and daily TV usage. Weighting reduced the bias between the longitudinal participants and the baseline sample, and also increased variance by 5% to 35% with a final weighting efficiency of 41.67%. CONCLUSIONS: We conclude that a weighting procedure is important to reduce longitudinal bias in health-oriented epidemiological studies and suggest identifying the most influencing variables in the first step, then use logistic regression modeling to calculate the inverse of the probability of participation in the second step, and finally trim and standardize the weights in the third step.