Marjan Mansourvar

Dr. Marjan Mansourvar


Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 September 2019 in Journal of Medical Internet Research
Verified
Journal Article
Open access
DPDaniel Hansen Pedersen
Daniel Hansen Pedersen
Marjan MansourvarMarjan Mansourvar
Marjan Mansourvar
CSCamilla Sortsø
Camilla Sortsø
TSThomas Schmidt
Thomas Schmidt
Background: The increasing prevalence and economic impact of chronic diseases challenge health care systems globally. Digital solutions can potentially improve efficiency and quality of care, but these initiatives struggle with nonusage attrition. Machine learning methods have been proven to predict dropouts in other settings but lack implementation in health care. Objective: This study aimed to gain insight into the causes of attrition for patients in an electronic health (eHealth) intervention for chronic lifestyle diseases and evaluate if attrition can be predicted and consequently prevented. We aimed to build predictive models that can identify patients in a digital lifestyle intervention at high risk of dropout by analyzing several predictor variables applied in different models and to further assess the possibilities and impact of implementing such models into an eHealth platform. Methods: Data from 2684 patients using an eHealth platform were iteratively analyzed using logistic regression, decision trees, and random forest models. The dataset was split into a 79.99% (2147/2684) training and cross-validation set and a 20.0% (537/2684) holdout test set. Trends in activity patterns were analyzed to assess engagement over time. Development and implementation were performed iteratively with health coaches. Results: Patients in the test dataset were classified as dropouts with an 89% precision using a random forest model and 11 predictor variables. The most significant predictors were the provider of the intervention, 2 weeks inactivity, and the number of advices received from the health coach. Engagement in the platform dropped significantly leading up to the time of dropout. Conclusions: Dropouts from eHealth lifestyle interventions can be predicted using various data mining methods. This can support health coaches in preventing attrition by receiving proactive warnings. The best performing predictive model was found to be the random forest.

1 February 2014 in Journal of Forensic and Legal Medicine
Verified
Journal Article
Closed access
Marjan MansourvarMarjan Mansourvar
Marjan Mansourvar
MIMaizatul Akmar Ismail
Maizatul Akmar Ismail
RRRam Raj
Ram Raj
SKSameem Abdul Kareem
Sameem Abdul Kareem
SASaw Aik
Saw Aik
CAChermaine Deepa Antony
Chermaine Deepa Antony

2 November 2021 in BMJ Open
Verified
Journal Article
Open access
PDF file
ANAmin Naemi
Amin Naemi
TSThomas Schmidt
Thomas Schmidt
Marjan MansourvarMarjan Mansourvar
Marjan Mansourvar
MNMohammad Naghavi-Behzad
Mohammad Naghavi-Behzad
AEAli Ebrahimi
Ali Ebrahimi
UWUffe Kock Wiil
Uffe Kock Wiil
Objectives This systematic review aimed to assess the performance and clinical feasibility of machine learning (ML) algorithms in prediction of in-hospital mortality for medical patients using vital signs at emergency departments (EDs). Design A systematic review was performed. Setting The databases including Medline (PubMed), Scopus and Embase (Ovid) were searched between 2010 and 2021, to extract published articles in English, describing ML-based models utilising vital sign variables to predict in-hospital mortality for patients admitted at EDs. Critical appraisal and data extraction for systematic reviews of prediction modelling studies checklist was used for study planning and data extraction. The risk of bias for included papers was assessed using the prediction risk of bias assessment tool. Participants Admitted patients to the ED. Main outcome measure In-hospital mortality. Results Fifteen articles were included in the final review. We found that eight models including logistic regression, decision tree, K-nearest neighbours, support vector machine, gradient boosting, random forest, artificial neural networks and deep neural networks have been applied in this domain. Most studies failed to report essential main analysis steps such as data preprocessing and handling missing values. Fourteen included studies had a high risk of bias in the statistical analysis part, which could lead to poor performance in practice. Although the main aim of all studies was developing a predictive model for mortality, nine articles did not provide a time horizon for the prediction. Conclusion This review provided an updated overview of the state-of-the-art and revealed research gaps; based on these, we provide eight recommendations for future studies to make the use of ML more feasible in practice. By following these recommendations, we expect to see more robust ML models applied in the future to help clinicians identify patient deterioration earlier.

16 December 2013 in Computational and Mathematical Methods in Medicine
Verified
Journal Article
Open access
PDF file
Marjan MansourvarMarjan Mansourvar
Marjan Mansourvar
MIMaizatul Akmar Ismail
Maizatul Akmar Ismail
Tutut HerawanTutut Herawan
Tutut Herawan
RRRam Raj
Ram Raj
SKSameem Abdul Kareem
Sameem Abdul Kareem
FNFariza Hanum Nasaruddin
Fariza Hanum Nasaruddin
Bone age assessment (BAA) of unknown people is one of the most important topics in clinical procedure for evaluation of biological maturity of children. BAA is performed usually by comparing an X-ray of left hand wrist with an atlas of known sample bones. Recently, BAA has gained remarkable ground from academia and medicine. Manual methods of BAA are time-consuming and prone to observer variability. This is a motivation for developing automated methods of BAA. However, there is considerable research on the automated assessment, much of which are still in the experimental stage. This survey provides taxonomy of automated BAA approaches and discusses the challenges. Finally, we present suggestions for future research.

24 September 2015 in PLOS ONE
Verified
Journal Article
Open access
PDF file
Marjan MansourvarMarjan Mansourvar
Marjan Mansourvar
SSShahaboddin Shamshirband
Shahaboddin Shamshirband
RRRam Raj
Ram Raj
RGRoshan Gunalan
Roshan Gunalan
IMIman Mazinani
Iman Mazinani
Assessing skeletal age is a subjective and tedious examination process. Hence, automated assessment methods have been developed to replace manual evaluation in medical applications. In this study, a new fully automated method based on content-based image retrieval and using extreme learning machines (ELM) is designed and adapted to assess skeletal maturity. The main novelty of this approach is it overcomes the segmentation problem as suffered by existing systems. The estimation results of ELM models are compared with those of genetic programming (GP) and artificial neural networks (ANNs) models. The experimental results signify improvement in assessment accuracy over GP and ANN, while generalization capability is possible with the ELM approach. Moreover, the results are indicated that the ELM model developed can be used confidently in further work on formulating novel models of skeletal age assessment strategies. According to the experimental results, the new presented method has the capacity to learn many hundreds of times faster than traditional learning methods and it has sufficient overall performance in many aspects. It has conclusively been found that applying ELM is particularly promising as an alternative method for evaluating skeletal age.

28 April 2016 in Entropy
Verified
Journal Article
Open access
PDF file
IMIman Mazinani
Iman Mazinani
ZIZubaidah Ismail
Zubaidah Ismail
SSShahaboddin Shamshirband
Shahaboddin Shamshirband
AHAhmad Mustafa Hashim
Ahmad Mustafa Hashim
Marjan MansourvarMarjan Mansourvar
Marjan Mansourvar
ENErfan Zal Nezhad
Erfan Zal Nezhad
This paper proposes a procedure to estimate tsunami wave forces on coastal bridges through a novel method based on Extreme Learning Machine (ELM) and laboratory experiments. This research included three water depths, ten wave heights, and four bridge models with a variety of girders providing a total of 120 cases. The research was designed and adapted to estimate tsunami bore forces including horizontal force, vertical uplift and overturning moment on a coastal bridge. The experiments were carried out on 1:40 scaled concrete bridge models in a wave flume with dimensions of 24 m × 1.5 m × 2 m. Two six-axis load cells and four pressure sensors were installed to the base plate to measure forces. In the numerical procedure, estimation and prediction results of the ELM model were compared with Genetic Programming (GP) and Artificial Neural Networks (ANNs) models. The experimental results showed an improvement in predictive accuracy, and capability of generalization could be achieved by the ELM approach in comparison with GP and ANN. Moreover, results indicated that the ELM models developed could be used with confidence for further work on formulating novel model predictive strategy for tsunami bore forces on a coastal bridge. The experimental results indicated that the new algorithm could produce good generalization performance in most cases and could learn thousands of times faster than conventional popular learning algorithms. Therefore, it can be conclusively obtained that utilization of ELM is certainly developing as an alternative approach to estimate the tsunami bore forces on a coastal bridge.