Mean percentage covariate bias–matched and unmatched samples <sup>a</sup>. VecchioNerina DaviesDebbie RohdeNicholas 2018 <p>Mean percentage covariate bias–matched and unmatched samples <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0202559#t005fn001" target="_blank"><sup>a</sup></a>.</p>