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External Validation of clinical prediction models - Statswork

External validation can take many forms, including validation in the field such as temporal, geographical and independent validation. For external validation studies, the sample size calculation estimates based on statistical power considerations have not been extensively investigated. Statswork offers statistical services as per the requirements of the customers. When you Order statistical Services at Statswork, we promise you the following u2013 Always on Time, outstanding customer support, and High-quality Subject Matter Experts.<br>Read More With Us: https://bit.ly/31Yy0mT<br>Why Statswork?<br>Plagiarism Free | Unlimited Support | Prompt Turnaround Times | Subject Matter Expertise | Experienced Bio-statisticians & Statisticians | Statistics across Methodologies | Wide Range of Tools & Technologies Supports | Tutoring Services | 24/7 Email Support | Recommended by Universities<br>Contact Us:<br>Website: www.statswork.com<br>Email: info@statswork.com<br>United Kingdom: 44-1143520021<br>India: 91-4448137070<br>WhatsApp: 91-8754446690<br>

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External Validation of clinical prediction models - Statswork

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  1. EXTERNALVALIDATIONOF CLINICALPREDICTION MODELS AnAcademicpresentationby Dr.NancyAgnes,Head,TechnicalOperations,Statswork Group www.statswork.com Email:info@statswork.com

  2. TODAY'SDISCUSSION Outline ExternalValidation Factorsinfluencesaffectexternalvalidationdata FutureScope

  3. Validation,particularlyexternalvalidation,isacrucialpartofdevelopingapredictive model. External validation is needed to ensure that a prediction model is generalizable to patientsother than thosein the derivativecohort. Externalvalidationcanbedonebytestingthemodel'soutputindatathatisn'tthesame asthe data used tocreate the model. Asaconsequence,itiscarriedoutafterthecreationofapredictionmodel.

  4. EXTERNAL VALIDATION Externalvalidationcantakemanyforms,includingvalidation in the field such as temporal, geographical and independent validation. For external validation studies, the sample size calculation estimates based on statistical power considerations have not beenextensively investigated. However, in order to achieve adequate model output in the validation set, a large sample size is needed to validate the predictionmodel.

  5. Thesamplesizeforexternalvalidationdataforthe implementation of the prediction model is affected by the numberof eventsandpredictors. FACTORS INFLUENCES AFFECT EXTERNAL VALIDATION DATA Externalvalidationofthepredictionmodelrequiresa minimumof100eventsand/ornon-events,accordingto simulationstudies,andasystematicanalysisfoundthat smallexternalvalidationstudiesareineffectiveand inaccurate. Example:Radiologyimagingisoftentreatedaseffective predictiveparametersandresearchersoftenvalidatethe findingsusingclinical predictionmodel. Contd...

  6. Every prediction model is based on the regression analysis. Themostcommonpredictivemodelortheregressionmodelusedfortheclinical prediction model are linear regression if the dependent variable is continuous in nature, logisticregressionmodelifthedependentvariableisbinary,andCox-proportional model if the dependent variable is time-to-event in nature. Al-Ameri et al (2020) presented a detailed review on clinical prediction models for liver transplantationstudy. Further, Ratna et al (2020) discussed the quality of clinical prediction model in vitro fertilisationand human reproduction. Validation of model has been carried out using re-sampling technique and measured the accuracyusingAUC,calibrationplotasshowninfigure1,c-index,andHosmer- Lemeshowteststatistic. Contd...

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  8. Figure1:SlopeofCalibrationplot(Source:StevensandPoppe(2020)) In addition, Stevens and Poppe (2020) suggested the Cox- calibration slope using logisticregressionmodelinsteadofusingsimplythecalibrationslopefor the predictivemodel. This suggestion has been made after the scrutiny of around 33 research articles and found that most of the validation are external validation and identified the validity using thecalibrationslopeandthesamplearticlesarepresentedinthefollowingtable. Contd...

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  11. Table1.StatedInterpretationofthe“CalibrationSlope”Source:StevensandPoppe(2020)Table1.StatedInterpretationofthe“CalibrationSlope”Source:StevensandPoppe(2020) Arjunetal(2020)consideredthepandemicmortalitystudyofCOVID19and discussedthedevelopmentandvalidationofclinicalpredictionmodel. Contd...

  12. FUTURE SCOPE Though many literature suggests several validation techniques for the predictive model, there is no such proper technique which can besuitable forall theclinical datasets. Further, proper adjustment has to be made for the calibration indextovalidatethepredictionmodelsuitableforallclinical datasets. Contd...

  13. ContactUs UNITEDKINGDOM +44-1143520021 INDIA +91-4448137070 EMAIL info@statswork.com

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