{
 "approved_by_author": "\u231b",
 "citation": "Zhang, Q., Vallerga, C.L., Walker, R.M. et al. Improved precision of epigenetic clock estimates across tissues and its implication for biological ageing. Genome Medicine 11, 54 (2019).",
 "citations": 550,
 "citations_date": "2026-10-02",
 "clock_name": "zhangen",
 "data_type": "DNA methylation",
 "doi": "https://doi.org/10.1186/s13073-019-0667-1",
 "journal": "Genome Medicine",
 "last_author": "Peter M. Visscher",
 "model_type": "elastic net regression",
 "n_features": 514,
 "notes": "Elastic-net chronological-age predictor released from the largest multi-cohort training set, using 514 selected CpGs from predominantly blood plus saliva data.",
 "platform": [
  "Illumina 450K",
  "Illumina EPIC"
 ],
 "population": "all ages",
 "predicts": [
  "chronological age"
 ],
 "preprocess": "scale_row",
 "reference_values": true,
 "research_only": null,
 "species": "Homo sapiens",
 "tissue": [
  "whole blood",
  "saliva"
 ],
 "training_target": [
  "chronological age"
 ],
 "unit": [
  "years"
 ],
 "version": "0.5.7",
 "year": 2019
}