Receiver operating characteristics (ROC) curves of different logistic regression models to discriminate between lame (NRS ≥ 2.5) and non-lame cows (NRS ≤ 2).

<p>First model (-∙-) includes standing bouts (AUC = 0.81), second model (─) includes walking speed_calc (AUC = 0.88); third model (- -) includes walking speed_calc and the number of standing bouts (AUC = 0.96); fourth model (∙∙∙) includes walking speed_calc, the number of standing bouts and the eating time (AUC = 0.96). NRS = numerical rating system according to Flower and Weary [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0155796#pone.0155796.ref038" target="_blank">38</a>]. AUC = area under the receiver operating characteristics curve.