Impact of the Target: Stroke quality improvement initiative. Impact of the Target: Stroke quality improvement initiative. Time trend in the proportion of patients with door-to-needle times for tPA ≤60 min during the preintervention and postintervention periods of Target: Stroke. Reproduced with permission from JAMA. 2014; 311(16):1632–1640. Copyright ©2014 American Medical Association. All rights reserved. tPA, tissue plasminogen activator. Cora H Ormseth et al. Stroke Vasc Neurol 2017;2:94-105 © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.