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I’m working on medical diagnostic data meta-analyses. Some data come from direct presentations of raw data, some from logistic-regression output, others from ROC curves, and I would like to know when it is defensible to “reverse-engineer” true-positive, false-positive, false-negative and true-negative counts from summary measures such as sensitivity, specificity or AUC or regression. Here’s what I’m looking for you to deliver: • A short, clearly written memo and/or a brief call that walks through and states whether the back-calculation is appropriate in a number of example case. I will be happy to provide additional explanation of intended methods (hsROC) and provide som examples of references or excerpts of published data that I am not sure is appropriate for "backwards" calculations of to fo fn tn from sensitivity and specificity. • If avaisble, citations or links to authoritative methods papers or guidelines explaining in which cases "backwards calculations" are appropriate
Project ID: 40621573
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Hey there Glane here, I can help assess when it is methodologically appropriate to back-calculate TP, FP, FN, and TN from reported diagnostic accuracy measures such as sensitivity, specificity, ROC/AUC, logistic regression outputs, and other summary statistics for your medical diagnostic meta-analysis. Using R (including packages such as mada, meta, and metafor where appropriate), I'll provide a concise, evidence-based memo explaining when reverse calculations are statistically defensible, discuss implications for hsROC models, review your example studies, and support the recommendations with authoritative methodological references and reporting guidelines to ensure your approach is robust and suitable for publication.
$20 USD in 1 day
6.1
6.1

I have a PhD in statistics with vast experience in studying data and running various statistical analyses. I can provide information with whether derived results can be used bacak.
$20 USD in 2 days
5.4
5.4

Affordable, Early Delivery. ★★★★★★★★★★★★★★I hold a Masters degree which gives me the requisite background to handle writing from various subjects. I am a highly committed person towards my work. You can rely on QualityXenter for quality and consistency in writing. We never violate copyright rules. I have vast amount of experience in this industry since I am working from 2015 as a professional writer. I provide many modifications till to get your satisfactions. I have access to enough journals to use in your research project. I always produce quality work at VERY LOW RATES so, don't worry if you have a low budget for your work, I will be very happy to make a new client like you. I am producing quality work for my clients including ARTICLE WRITING, REPORT WRITING, ESSAY WRITING, RESEARCH PAPERS, BUSINESS PLAN, TECHNICAL WRITING, MATLAB, THESIS, ACCOUNTING & FINANCE work ETC. Go through my profile link https://www.freelancer.com/u/qualityxenter
$10 USD in 1 day
4.6
4.6

Hi there, I'm Dr. Hany, a seasoned medical writer and biostatistical analyst with a powerful fusion of clinical proficiency and statistical skills to offer. Your project warrants an exceptional blend of analytical abilities and medical domain insights, which my professional journey perfectly embodies. I believe my expertise in merging advanced data analysis with impactful medical content aligns flawlessly with your data suitability assessment needs for your medical diagnostic research. Let’s discuss your issues on true examples to sort it out and find out how reverse engineering can be achieved.
$150 USD in 7 days
4.6
4.6

Reverse-engineering diagnostic accuracy metrics from summary statistics requires careful consideration of mathematical validity and clinical defensibility—this memo addresses exactly that constraint. The project involves translating between different data representations (raw counts, logistic regression coefficients, ROC curves) and determining when back-calculations preserve statistical integrity. Deliverable structure: A technical memo systematizing the conditions under which sensitivity/specificity reversals, AUC decompositions, and regression-based reconstructions are mathematically sound. Each case will include threshold analysis, information loss assessment, and confidence interval propagation concerns. Examples from your provided data will be evaluated against established biostatistical literature. The memo will cite authoritative guidelines from sources including Pepe's ROC curve methodology papers, DeLong et al. on AUC estimation, and relevant sections from Fawcett's technical framework. Where back-calculations introduce unacceptable assumptions or data loss, alternative analytical approaches will be flagged. Delivery includes the written memo plus one structured call to walk through methodological reasoning for your specific hsROC context and clarify edge cases in your reference excerpts.
$10 USD in 1 day
4.0
4.0

This project immediately caught my attention because it is exactly the type of work I do best. Your need for guidance on "reverse-engineering" true-positive and false-negative counts from summary measures like sensitivity and specificity aligns perfectly with my expertise. I understand the importance of ensuring that your meta-analyses are built on clean, professional, and user-friendly methodologies. While I am new to freelancer, I have tons of experience and have done other projects off site. My background includes extensive work in medical statistics and data interpretation, enabling me to deliver clear memos and provide authoritative citations for your case studies. If this sounds like what you're looking for I'd love to hear more about your project. Regards, Warrick Van Eeden
$10 USD in 7 days
0.0
0.0

My background combines laboratory science, analytical method validation, and statistical analysis, giving me extensive experience interpreting diagnostic performance metrics and scientific research. I routinely work with sensitivity, specificity, predictive values, ROC analysis, logistic regression, and validation of analytical methods, always with an emphasis on scientific rigor and reproducibility. For this project, I can: * Review published studies and determine whether reconstruction of TP, FP, FN, and TN is methodologically justified. * Explain the assumptions required when deriving confusion matrices from reported sensitivity, specificity, prevalence, sample size, logistic regression outputs, or ROC-derived metrics. * Prepare a concise, evidence-based memo summarizing which approaches are appropriate, which should be avoided, and why. * Support recommendations with references from peer-reviewed methodological literature and established guidance on diagnostic test accuracy meta-analysis, including HSROC and related approaches.
$20 USD in 7 days
0.0
0.0

Hi, This is a question I can answer properly. I'm a PhD data scientist (Computer Science, Georgia State) doing postdoctoral research at Columbia, with 25+ peer-reviewed papers and heavy use of sensitivity/specificity/ROC evaluation in diagnostic-style classification work. The short version of my view, which the memo would develop with citations: - Se and Sp plus the diseased and non-diseased group sizes give you TP/FN/TN/FP exactly, subject only to rounding. That case is defensible, and the rounding uncertainty is quantifiable. - Se and Sp with only a total N and no group breakdown is not identifiable. Any reconstruction assumes a prevalence, and the assumption has to be stated and tested. - AUC alone does not identify a 2x2 table. Recovering one needs a distributional assumption (typically binormal) and a threshold choice; that is a modelling decision, not a back-calculation, and it should not feed an HSROC/bivariate model as if it were observed data. - Regression output is case by case, depending on whether the reported quantities pin down a threshold. Deliverable: a short memo working through each of your examples with a defensible / not defensible verdict and the reasoning, plus citations to the HSROC and bivariate methods literature and the Cochrane DTA guidance. Call included. Happy to look at your excerpts first. Best, Sarwan
$15 USD in 3 days
0.0
0.0

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