IRCT2015062922979N1 IRCT 2015-08-28 Vice chancellor for research,Tehran University Of Medical Sciences The effect of formative assessment and feedback on arterial blood gases interpretation skill Clinical trial comparing the effect of two kinds of written- oral feedback and written feedback in formative assessment to increase arterial blood gases interpretation skill in ICU nurses 2015-07-04 anticipated 90 Complete https://irct.ir/trial/19717 interventional Randomization: Not randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Other. N/A Comparison of formative assessment and provide appropriate feedback on arterial blood gases interpretation skill.. Intervention 1: In group of formative assessment with written and oral feedback, before educational session a written quiz will be taken from the educated items in previous session. After correcting papers, moreover, the correction will be determined and correct answers will be checked and necessary description will be written for correct answers. Also oral discussion will be held about participant’s errors and oral feedback will be given to participants. Intervention 2: In group of formative assessment with written feedback, before educational session a written quiz will be taken from the educated items in previous session. After correcting papers, only errors will be determined and correct answers will be checked and all the papers will be returned to participants.