ArticleBMC medical research methodology2022
KMSubtraction: reconstruction of unreported subgroup survival data utilizing published Kaplan-Meier survival curves.
Article in BMC medical research methodology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers, 4 of them syntheses that pooled it.
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Who cites it
23 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- Efficacy of first-line immune checkpoint inhibitors for recurrent/metastatic head and neck cancer: a systematic review and meta-analysis.Immunotherapy · 2026Pooled it
- Long-term outcomes of additional surgical versus nonsurgical treatment after non-curative endoscopic resection for T1 superficial esophageal cancer.International journal of surgery (London, England) · 2026Pooled it
- Pooled it
- First-line immune checkpoint inhibitors in low programmed death-ligand 1-expressing population.Frontiers in pharmacology · 2024Pooled it
- Pembrolizumab-Chemotherapy Versus Pembrolizumab in Head and Neck Squamous Cell Carcinoma: A PD-L1 CPS-Stratified Analysis of Updated KEYNOTE-048 Data.International journal of cancer · 2026Trial
- Visual extraction of individual patient data from published kaplan-meier survival plots using a web-based application offering different reconstruction methods (V-Exploder).BMC medical research methodology · 2026Article
- Zanidatamab vs trastuzumab with or without PD-1 blockade in HER2-positive metastatic gastric cancer: a reconstructed patient-level pooled analysis.The oncologist · 2026Article
- Article
- Adjuvant chemo-immunotherapy shows comparable efficacy among mismatch-repair-deficient and mismatch-repair-proficient stage III colon cancer: an exploratory, reconstructed individual patient-level data analysis.Journal for immunotherapy of cancer · 2026Article
- Exploring the optimal regimen in advanced hepatocellular carcinoma: a protocol of individual patient data network meta-analysis of randomized controlled trials.Frontiers in immunology · 2026Article
- Review
- Reconstructing patient level survival data from published Kaplan-Meier curves.Contemporary clinical trials communications · 2025Article
- Investigating the Synergistic Effects of Pembrolizumab and Chemotherapy in Gastric and Gastroesophageal Junction Cancer.Journal of gastric cancer · 2025Article
- PD-L1 expression as a negative predictive biomarker in advanced esophageal squamous-cell cancer treated with chemotherapy alone.ESMO gastrointestinal oncology · 2025Article
- Review
- PD-L1 expression predicts the efficacy of PD-1 blockade plus chemotherapy versus chemotherapy alone in treatment-naïve advanced or metastatic gastric cancer: a pooled analysis of reconstructed individual patient-level data from two randomized trials.Frontiers in cell and developmental biology · 2025Article
- Construction and Validation of a T Cell Exhaustion-Related Prognostic Signature in Cholangiocarcinoma.International journal of genomics · 2025Article
- Comparison of immune checkpoint inhibitors in combination with chemotherapy versus chemotherapy alone in the first-line treatment of advanced gastric cancer patients with low PD-L1 expression: a systematic review and meta-analysis.Therapeutic advances in medical oncology · 2025Article
- Cost-effectiveness analysis of sugemalimab combined with chemotherapy as first-line treatment for advanced gastric cancer.Frontiers in public health · 2025Article
- Cost-effectiveness of sequential treatment strategies involving first-line pembrolizumab with trastuzumab and chemotherapy for unresectable metastatic HER2-positive gastric or gastroesophageal junction adenocarcinoma.Therapeutic advances in medical oncology · 2025Article
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7 authors.
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Abstract
backgroundData from certain subgroups of clinical interest may not be presented in primary manuscripts or conference abstract presentations. In an effort to enable secondary data analyses, we propose a workflow to retrieve unreported subgroup survival data from published Kaplan-Meier (KM) plots.
methodsWe developed KMSubtraction, an R-package that retrieves patients from unreported subgroups by matching participants on KM plots of the overall cohort to participants on KM plots of a known subgroup with follow-up time. By excluding matched patients, the opposing unreported subgroup may be retrieved. Reproducibility and limits of error of the KMSubtraction workflow were assessed by comparing unmatched patients against the original survival data of subgroups from published datasets and simulations. Monte Carlo simulations were utilized to evaluate the limits of error of KMSubtraction.
resultsThe validation exercise found no material systematic error and demonstrates the robustness of KMSubtraction in deriving unreported subgroup survival data. Limits of error were small and negligible on marginal Cox proportional hazard models comparing reconstructed and original survival data of unreported subgroups. Extensive Monte Carlo simulations demonstrate that datasets with high reported subgroup proportion (r = 0.467, p < 0.001), small dataset size (r = - 0.374, p < 0.001) and high proportion of missing data in the unreported subgroup (r = 0.553, p < 0.001) were associated with uncertainty are likely to yield high limits of error with KMSubtraction.
conclusionKMSubtraction demonstrates robustness in deriving survival data from unreported subgroups. The limits of error of KMSubtraction derived from converged Monte Carlo simulations may guide the interpretation of reconstructed survival data of unreported subgroups.
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