BMC Medical Research Methodology

Article	Citations
Does imbalance in chest X-ray datasets produce biased deep learning approaches for COVID-19 screening?	440
coreSCD: multi-stakeholder consensus on core outcomes for sickle cell disease clinical trials	329
A gated group sequential design for seamless Phase II/III trial with subpopulation selection	276
Comparing statistical methods in assessing the prognostic effect of biomarker variability on time-to-event clinical outcomes	211
Understanding facilitators of research participation among adults with self-reported chronic pain – a survey examining hypothetical research participation	193
Correction: In health research publications, the number of authors is strongly associated with collective self-citations but less so with citations by others	125
More than one third of clinical practice guidelines on low back pain overlap in AGREE II appraisals. Research wasted?	99
Recruitment methods and yield rates in a clinical trial of physical exercise for older adults with hypertension—HAEL Study: a study within a trial	95
Handling of missing component information for common composite score outcomes used in axial spondyloarthritis research when complete-case analysis is unbiased	85
External validation of existing dementia prediction models on observational health data	77
Statistical methods in the analysis of multicentre HIV randomized controlled trials in the African region: a scoping review	75
Clinical systematic reviews – a brief overview	73
How likely is unmeasured confounding to explain meta-analysis-derived associations between alcohol, other substances, and mood-related conditions with HIV risk behaviors?	73
regCOVID: Tracking publications of registered COVID-19 studies	66
Causal effect of chemotherapy received dose intensity on survival outcome: a retrospective study in osteosarcoma	64
Modelling of intensive care unit (ICU) length of stay as a quality measure: a problematic exercise	64
Technologies for frailty, comorbidity, and multimorbidity in older adults: a systematic review of research designs	62
Mind the gap: covariate constrained randomisation can protect against substantial power loss in parallel cluster randomised trials	61
A Bayesian network perspective on neonatal pneumonia in pregnant women with diabetes mellitus	59
Developing survey weights to ensure representativeness in a national, matched cohort study: results from the children and young people with Long Covid (CLoCk) study	58
MetaAnalyst: a user-friendly tool for metagenomic biomarker detection and phenotype classification	57
Methodological aspects for accelerometer-based assessment of physical activity in heart failure and health	57
A data-driven pipeline to extract potential adverse drug reactions through prescription, procedures and medical diagnoses analysis: application to a cohort study of 2,010 patients taking hydroxychloro	54
Estimation of marginal structural models under irregular visits and unmeasured confounder: calibrated inverse probability weights	53
CalScope: methodology and lessons learned for conducting a remote statewide SARS-CoV-2 seroprevalence study in California using an at-home dried blood spot collection kit and online survey	52

Contextual effects: how to, and how not to, quantify them	51
Power and sample size calculation for incremental net benefit in cost effectiveness analyses with applications to trials conducted by the Canadian Cancer Trials Group	51
A framework to model global, regional, and national estimates of intimate partner violence	51
The impact of iterative removal of low-information cluster-period cells from a stepped wedge design	49
Choices of measures of association affect the visualisation and composition of the multimorbidity networks	47
Should RECOVERY have used response adaptive randomisation? Evidence from a simulation study	47
Pre-statistical harmonization of behavioral instruments across eight surveys and trials	47
Design and analysis of outcomes following SARS-CoV-2 infection in veterans	46
Using group testing in a two-phase epidemiologic design to identify the effects of a large number of antibody reactions on disease risk	45
Joint modelling of multivariate longitudinal clinical laboratory safety outcomes, concomitant medication and clinical adverse events: application to artemisinin-based treatment during pregnancy clinic	44
An algorithm to assess importance of predictors in systematic reviews of prediction models: a case study with simulations	42
A study within a trial (SWAT) of clinical trial feasibility and barriers to recruitment in the United Kingdom – the CapaCiTY programme experience	40
The effect of high prevalence of missing data on estimation of the coefficients of a logistic regression model when using multiple imputation	40
Analytical challenges in estimating the effect of exposures that are bounded by follow-up time: experiences from the Blood Stream Infection—Focus on Outcomes study	40
Assessing and adjusting for bias in ecological analysis using multiple sample datasets	39
A systematic review of methods to estimate colorectal cancer incidence using population-based cancer registries	38
Binary classification with fuzzy logistic regression under class imbalance and complete separation in clinical studies	37
Misspecification of confounder-exposure and confounder-outcome associations leads to bias in effect estimates	37
The reliance on conceptual frameworks in qualitative research – a way forward	37
Study retention and attrition in a longitudinal cohort study including patient-reported outcomes, fieldwork and biobank samples: results of the Netherlands quality of life and Biomedical cohort study	37
Methodology and experiences of rapid advice guideline development for children with COVID-19: responding to the COVID-19 outbreak quickly and efficiently	36
Measuring the impact of zero-cases studies in evidence synthesis practice using the harms index and benefits index (Hi-Bi)	35
Improving retention of community-recruited participants in HIV prevention research through Saturday household visits; findings from the HPTN 071 (PopART) study in South Africa	35
Discretizing multiple continuous predictors with U-shaped relationships with lnOR: introducing the recursive gradient scanning method in clinical and epidemiological research	33
Fidelity, pragmatism and the “grey line” in between—exploring the delivery of a pragmatic physical activity randomised controlled trial—a secondary analysis	33
Measuring bereavement prevalence in a complex sampling survey: the 2019 Georgia Behavioral Risk Factor Surveillance System (BRFSS)	33
Comparison of two propensity score-based methods for balancing covariates: the overlap weighting and fine stratification methods in real-world claims data	31
Evaluating methods to define place of residence in Canadian administrative data and the impact on observed associations with all-cause mortality in type 2 diabetes	31
Optimising research investment by simulating and evaluating monitoring strategies to inform a trial: a simulation of liver fibrosis monitoring	31
Using joint models to study the association between CD4 count and the risk of death in TB/HIV data	31
Effect of alcohol consumption on breast cancer: probabilistic bias analysis for adjustment of exposure misclassification bias and confounders	30
Blinded sample size re-estimation in a comparative diagnostic accuracy study	29
Bayesian additional evidence for decision making under small sample uncertainty	29
Using web conferencing to engage Aboriginal and Torres Strait Islander young people in research: a feasibility study	28
Identifying Potential Factors Associated with High HIV viral load in KwaZulu-Natal, South Africa using Multiple Correspondence Analysis and Random Forest Analysis	27
Development and validation of paired MEDLINE and Embase search filters for cost-utility studies	27
Cause of death coding in asthma	26
Reporting of methods to prepare, pilot and perform data extraction in systematic reviews: analysis of a sample of 152 Cochrane and non-Cochrane reviews	26
Target trial emulation with multi-state model analysis to assess treatment effectiveness using clinical COVID-19 data	26
A photograph of the researcher on the invitation letter did not affect the participation rate of a postal survey: a randomized study within a trial (SWAT)	24
Predicting postoperative surgical site infection with administrative data: a random forests algorithm	24
Machine learning computational tools to assist the performance of systematic reviews: A mapping review	24
Comparison of analysis methods and design choices for treatment-by-period interaction in unidirectional switch designs: a simulation study	24
Bayesian spatial-temporal analysis and determinants of cardiovascular diseases in Tanzania mainland	24
Prevalence of evidence of inconsistency and its association with network structural characteristics in 201 published networks of interventions	23
Correction to: Applying a novel approach to scoping review incorporating artificial intelligence: mapping the natural history of gonorrhoea	23
Structured expert elicitation to inform long-term survival extrapolations using alternative parametric distributions: a case study of CAR T therapy for relapsed/ refractory multiple myeloma	23
SurvdigitizeR: an algorithm for automated survival curve digitization	23
The potential impact fraction of population weight reduction scenarios on non-communicable diseases in Belgium: application of the g-computation approach	23
Accounting for bias due to outcome data missing not at random: comparison and illustration of two approaches to probabilistic bias analysis: a simulation study	22

TRIPLE C reporting principles for case study evaluations of the role of context in complex interventions	22
Opportunities and obstacles in linking large health care registries: the primary secondary cancer care registry - breast cancer	22
Feasibility of a hybrid clinical trial for respiratory virus detection in toddlers during the influenza season	22
Documenting patients’ and providers’ preferences when proposing a randomized controlled trial: a qualitative exploration	21
MSMpred: interactive modelling and prediction of individual evolution via multistate models	21
Practical basket design for binary outcomes with control of family-wise error rate	21
A PubMed search filter for efficiently retrieving exercise training studies	21
Correction: Individual patient data to allow a more elaborated comparison of trial results with real-world outcomes from second-line immunotherapy in NSCLC	21
A validation study of data in the National Tonsil Surgery Register in Sweden: high agreement with medical records ensures that data can be used to monitor clinical practices and outcomes	21
Comparison of methods for tuning machine learning model hyper-parameters: with application to predicting high-need high-cost health care users	20
Interrater reliability estimators tested against true interrater reliabilities	20
Comparison of generic and specific instruments to assess the quality of life in patients with melasma	20
Development and evaluation of a search filter to identify prognostic factor studies in Ovid MEDLINE	20
A comparison of survival models for prediction of eight-year revision risk following total knee and hip arthroplasty	20
Using random-forest multiple imputation to address bias of self-reported anthropometric measures, hypertension and hypercholesterolemia in the Belgian health interview survey	20
Evaluating methods for Lasso selective inference in biomedical research: a comparative simulation study	19
Standardizing registry data to the OMOP Common Data Model: experience from three pulmonary hypertension databases	19
Adjusting expected deaths for mortality displacement during the COVID-19 pandemic: a model based counterfactual approach at the level of individuals	19
Bayesian variable selection and survival modeling: assessing the Most important comorbidities that impact lung and colorectal cancer survival in Spain	19
Application of machine learning in predicting survival outcomes involving real-world data: a scoping review	19
Implications of analysing time-to-event outcomes as binary in meta-analysis: empirical evidence from the Cochrane Database of Systematic Reviews	19
Genetic matching for time-dependent treatments: a longitudinal extension and simulation study	19
A roadmap to using randomization in clinical trials	19
Development and validation of a model to identify polycystic ovary syndrome in the French national administrative health database	18
Estimation and inference for the mediation effect in a time-varying mediation model	18
Data-driven prediction of COVID-19 cases in Germany for decision making	18
Comparison of the effects of imputation methods for missing data in predictive modelling of cohort study datasets	18
Elucidating vaccine efficacy using a correlate of protection, demographics, and logistic regression	18
Correction: A scoping review of statistical methods in studies of biomarker-related treatment heterogeneity for breast cancer	18
Inadequate reporting quality of registered genome editing trials: an observational study	18
Development of a standardized patient-reported clinical questionnaire for children with spinal pain	18
Adjusting for Berkson error in exposure in ordinary and conditional logistic regression and in Poisson regression	17
CAT HPPR: a critical appraisal tool to assess the quality of systematic, rapid, and scoping reviews investigating interventions in health promotion and prevention	17
Evaluating the performance of propensity score matching based approaches in individual patient data meta-analysis	17
The methodological quality of systematic reviews regarding the Core Outcome Set (COS) development	17
Challenges in measurement of adolescent mental health: how are gender patterns affected when level of symptoms is analysed simultaneously with impairment?	17
SpatialWavePredict: a tutorial-based primer and toolbox for forecasting growth trajectories using the ensemble spatial wave sub-epidemic modeling framework	17
Text analysis framework for identifying mutations among non-small cell lung cancer patients from laboratory data	17
A flexible approach for variable selection in large-scale healthcare database studies with missing covariate and outcome data	17
Predicting kidney graft function and failure among kidney transplant recipients	17
Evaluation of intervention systematic reviews on chronic non-communicable diseases and lifestyle risk factors in low-middle income countries: meta-research	17
Exploring flexible polynomial regression as a method to align routine clinical outcomes with daily data capture through remote technologies	17
Comparison of Pocock and Simon’s covariate-adaptive randomization procedures in clinical trials	16
The difference between concealment and blinding in clinical trials and why both are important. A reply to Garg and Mickenautsch, BMC Medical Research Methodology (2022) 22:17	16
Stroke survivors’ preferences regarding study participation in rehabilitation research	16
Correction to: Applied comparison of large-scale propensity score matching and cardinality matching for causal inference in observational research	16
Does the feedback of blood results in observational studies influence response and consent? A randomised study of the Understanding Society Innovation Panel	16
Locating and testing the healthy context paradox: examples from the INCLUSIVE trial	16
Concordance between humans and GPT-4 in appraising the methodological quality of case reports and case series using the Murad tool	16
Estimating causal effects in the presence of competing events using regression standardisation with the Stata command standsurv	16
Stacked survival models for residual lifetime data	16
Inconsistencies in self-reported diabetes in a large panel study: the Survey of Health, Ageing and Retirement in Europe (SHARE)	15
Comparing single and multiple imputation strategies for harmonizing substance use data across HIV-related cohort studies	15
Prescription Sequence Symmetry Analysis (PSSA) to assess prescribing cascades: a step-by-step guide	15
Recruiting and retaining community-based participants in a COVID-19 longitudinal cohort and social networks study: lessons from Victoria, Australia	15
Protocol implementation during the COVID-19 pandemic: experiences from a randomized trial of stress ulcer prophylaxis	15
Network analysis for estimating standardization trends in genomics using MEDLINE	15
Systematic comparison of approaches to analyze clustered competing risks data	15
Selecting a randomization method for a multi-center clinical trial with stochastic recruitment considerations	15
Analysing cluster randomised controlled trials using GLMM, GEE1, GEE2, and QIF: results from four case studies	15
Symptom clusters among cancer survivors: what can machine learning techniques tell us?	15
Individual-specific networks for prediction modelling – A scoping review of methods	15
Piloting an automated clinical trial eligibility surveillance and provider alert system based on artificial intelligence and standard data models	15
Association of ABO blood groups with venous thrombosis recurrence in middle-aged patients: insights from a weighted Cox analysis dedicated to ambispective design	15
Determining diagnosis date of diabetes using structured electronic health record (EHR) data: the SEARCH for diabetes in youth study	15
A scoping review on the methodological and reporting quality of scoping reviews in China	15
Development of the multivariate administrative data cystectomy model and its impact on misclassification bias	14
Estimating reference intervals from an IPD meta-analysis using quantile regression	14
Multi-arm multi-stage (MAMS) randomised selection designs: impact of treatment selection rules on the operating characteristics	14
Bias amplification in the g-computation algorithm for time-varying treatments: a case study of industry payments and prescription of opioid products	14
Sample size recalculation in three-stage clinical trials and its evaluation	14
Agreement test of P value versus Bayes factor for sample means comparison: analysis of articles from the Angle Orthodontist journal	14
Methodological perspectives on the study of the health effects of unemployment – reviewing the mode of unemployment, the statistical analysis method and the role of confounding factors	13
Ranking of treatments in network meta-analysis: incorporating minimally important differences	13
Evaluation of data imputation strategies in complex, deeply-phenotyped data sets: the case of the EU-AIMS Longitudinal European Autism Project	13
Automated medical chart review for breast cancer outcomes research: a novel natural language processing extraction system	13
Development and validation of a distributed representation model of Japanese high-dimensional administrative claims data for clinical epidemiology studies	13
Prospective sampling bias in COVID-19 recruitment methods: experimental evidence from a national randomized survey testing recruitment materials	13
Grey literature scoping review: a synthesis of the application of participatory methodologies in underrepresented groups at an elevated risk of dementia	13
Reporting of flow diagrams in randomised controlled trials published in periodontology and implantology: a survey	13

The impact of heterogeneity on the analysis of platform trials with normally distributed outcomes	13
Adaptation and psychometric assessment of a sexual and reproductive empowerment scale in Arabic among refugee and non-refugee adolescent girls	13
Correction: CRIME‑Q—a unifying tool for critical appraisal of methodological (technical) quality, quality of reporting and risk of bias in animal research	13
The relationship of publication language, study population, risk of bias, and treatment effects in acupuncture related systematic reviews: a meta-epidemiologic study	13
Multi-group global tests for restricted mean survival time and restricted mean time lost: a variable transformation approach	13
The effect of dichotomization of skewed adjustment covariates in the analysis of clinical trials	13
Penalized landmark supermodels (penLM) for dynamic prediction for time-to-event outcomes in high-dimensional data	12
Multiply robust estimator for the difference in survival functions using pseudo-observations	12
The gap between statistical and clinical significance: time to pay attention to clinical relevance in patient-reported outcome measures of insomnia	12
Machine learning is an effective method to predict the 90-day prognosis of patients with transient ischemic attack and minor stroke	12
Correction: Sampling strategies to evaluate the prognostic value of a new biomarker on a time-to-event end-point	12
Patient-centered infertility questionnaire for female clients (PCIQ-F): part I: questionnaire development	12
Some examples of privacy-preserving sharing of COVID-19 pandemic data with statistical utility evaluation	12
Correction: Feasibility of a hybrid clinical trial for respiratory virus detection in toddlers during the influenza season	12
Comparison of Bayesian Networks, G-estimation and linear models to estimate causal treatment effects in aggregated N-of-1 trials with carry-over effects	12
High-dimensional mediation analysis for continuous outcome with confounders using overlap weighting method in observational epigenetic study	12
Correction: Evaluating quasi-experimental approaches for estimating epidemiological efficacy of non-randomised field trials: applications in Wolbachia interventions for dengue	12
Accommodating heterogeneous missing data patterns for prostate cancer risk prediction	12
Methodological guidance for the evaluation and updating of clinical prediction models: a systematic review	12
Determining the extent and frequency of on-site monitoring: a bayesian risk-based approach	12
Longitudinal plasmode algorithms to evaluate statistical methods in realistic scenarios: an illustration applied to occupational epidemiology	12
Development of an Aboriginal Resilience and Recovery Questionnaire – a collaboration between practitioners and help-seeking clients of a Victorian Aboriginal community controlled health service	12
Correction: Impact of sampling and data collection methods on maternity survey response: a randomised controlled trial of paper and push-to-web surveys and a concurrent social media survey	12
Advancing guideline quality through country-wide and regional quality assessment of CPGs using AGREE: a scoping review	12
A logical analysis of null hypothesis significance testing using popular terminology	12
Bayesian dynamic borrowing in group-sequential design for medical device studies	11
Evidence pointing toward invalidity of the SF-8 physical and mental scales: a fusion validity assessment	11
Measuring advance care planning behavior in Dutch adults: translation, cultural adaptation and validation of the Advance Care Planning Engagement Survey	11
Design and statistical analysis reporting among interrupted time series studies in drug utilization research: a cross-sectional survey	11
How important is the linearity assumption in a sample size calculation for a randomised controlled trial where treatment is anticipated to affect a rate of change?	11
Multimorbidity prevalence and health outcome prediction: assessing the impact of lookback periods, disease count, and definition criteria in health administrative data at the population-based level	11
The classification algorithms to support the management of the patient with femur fracture	11
Propensity score analysis for health care disparities: a deweighting approach	11
Sensitivity analyses for data missing at random versus missing not at random using latent growth modelling: a practical guide for randomised controlled trials	11
Count data models for outpatient health services utilisation	11
Left-censored recurrent event analysis in epidemiological studies: a proposal for when the number of previous episodes is unknown	11
Modeling of atrophy size trajectories: variable transformation, prediction and age-of-onset estimation	11
Converting from face-to-face to postal follow-up and its effects on participant retention, response rates and errors: lessons from the EQUAL study in the UK	11
Negative log-binomial model with optimal robust variance to estimate the prevalence ratio, in cross-sectional population studies	11
nlive: an R package to facilitate the application of the sigmoidal and random changepoint mixed models	11
Performance metrics for models designed to predict treatment effect	11
Borrowing information across patient subgroups in clinical trials, with application to a paediatric trial	11
A comparison of frequentist and Bayesian approaches to the Personalised Randomised Controlled Trial (PRACTical)—design and analysis considerations	11
Handling missing values in patient-reported outcome data in the presence of intercurrent events	11
Constructing within and between hospital physician social networks for modeling physician research participation	10
The validity, reliability and feasibility of four instruments for assessing the consciousness of stroke patients in a neurological intensive care unit compared	10
Bayesian Mendelian randomization with an interval causal null hypothesis: ternary decision rules and loss function calibration	10
Identification of patients’ smoking status using an explainable AI approach: a Danish electronic health records case study	10
Predicting lung cancer survival prognosis based on the conditional survival bayesian network	10
Advancements in predicting and modeling rare event outcomes for enhanced decision-making	10
The minimal important difference of patient-reported outcome measures related to female urinary incontinence: a systematic review	10
Sample size calculation for prevalence studies using Scalex and ScalaR calculators	10
Understanding multimorbidity: insights with graphical models	10
The conclusiveness of trial sequential analysis varies with estimation of between-study variance: a case study	10
Ensuring cross-cultural data comparability by means of anchoring vignettes in heterogeneous refugee samples	10
Are morbidity and mortality estimates from randomized controlled trials externally valid? A comparison of outcomes among infants enrolled into an RCT or a cohort study in Botswana	10
Informed Bayesian survival analysis	10
Comparing outcomes from tailored meta-analysis with outcomes from a setting specific test accuracy study using routine data of faecal calprotectin testing for inflammatory bowel disease	10
Addressing treatment switching in the ALTA-1L trial with g-methods: exploring the impact of model specification	10
Analysis of applying a patient safety taxonomy to patient and clinician-reported incident reports during the COVID-19 pandemic: a mixed methods study	10
Estimating effects of health policy interventions using interrupted time-series analyses: a simulation study	10
Interchangeability and optimization of heart rate methods for estimating oxygen uptake in ergometer cycling, level treadmill walking and running	10
Standard of care for COVID-19 in randomized clinical trials registered in trial registries and published in preprint servers and scholarly journals: a cross-sectional study	10
Adjusting for outcome risk factors in immigrant datasets: total or direct effects?	10
BivRec: an R package for the nonparametric and semiparametric analysis of bivariate alternating recurrent events	10
Two-step spatiotemporal anomaly detection corrected for lag reporting time with application to real-time dengue surveillance in Thailand	10
Evaluation of the Fill-it-up-design to use historical control data in randomized clinical trials with two arm parallel group design	10
Patient regional index: a new way to rank clinical specialties based on outpatient clinics big data	10
Methodological approaches to measuring the incidence of unplanned emergency department presentations by cancer patients receiving systemic anti-cancer therapy: a systematic review	10
Grouped data with survey revision	10
Longitudinal mediation analysis with multilevel and latent growth models: a separable effects causal approach	10
Recruitment into antibody prevalence studies: a randomized trial of postcards vs. letters as invitations	10
Impact of methodological choices in comparative effectiveness studies: application in natalizumab versus fingolimod comparison among patients with multiple sclerosis	9
Segmentation of patients with small cell lung cancer into responders and non-responders using the optimal cross-validation technique	9
Two-stage group-sequential designs with delayed responses – what is the point of applying corresponding methods?	9
Assessing the ability of an instrumental variable causal forest algorithm to personalize treatment evidence using observational data: the case of early surgery for shoulder fracture	9
CRIME-Q—a unifying tool for critical appraisal of methodological (technical) quality, quality of reporting and risk of bias in animal research	9
Streamlining systematic reviews with large language models using prompt engineering and retrieval augmented generation	9
Gaps in the usage and reporting of multiple imputation for incomplete data: findings from a scoping review of observational studies addressing causal questions	9
A comprehensive guide to study the agreement and reliability of multi-observer ordinal data	9
Correction: A non-parametric approach to predict the recruitment for randomized clinical trials: an example in elderly inpatient settings	9
A systematic review and psychometric evaluation of resilience measurement scales for people living with dementia and their carers	9
Quality of guidelines for infection management in sepsis: a critical appraisal using the AGREE II instrument	9
Problematic meta-analyses: Bayesian and frequentist perspectives on combining randomized controlled trials and non-randomized studies	9
A new infodemiological approach through Google Trends: longitudinal analysis of COVID-19 scientific and infodemic names in Italy	9
Analyzing missingness patterns in real-world data using the SMDI toolkit: application to a linked EHR-claims pharmacoepidemiology study	9
Tailored approach to participant recruitment and retention to maximize health equity in pediatric cancer research	9
Developing the intersectionality supplemented Consolidated Framework for Implementation Research (CFIR) and tools for intersectionality considerations	9
When a joint model should be preferred over a linear mixed model for analysis of longitudinal health-related quality of life data in cancer clinical trials	9
Prior test experience confounds longitudinal tracking of adolescent cognitive and motor development	9
Integrating fractional-order SEI1I2I3QCR model with awareness and non-pharmaceutical interventions for optimal COVID-19 pandemic	9
Meta-analysis under imbalance in measurement of confounders in cohort studies using only summary-level data	9
Should multiple imputation be stratified by exposure group when estimating causal effects via outcome regression in observational studies?	9
Use and misuse of random forest variable importance metrics in medicine: demonstrations through incident stroke prediction	9
Major mistakes or errors in the use of trial sequential analysis in systematic reviews or meta-analyses – the METSA systematic review	9