Abstract The University of Manchester Panagiota Gardeli Degree Title: Doctor of Philosophy (Ph.D.) How Greek nurses' personal postoperative experiences influence their behavior towards patient's postoperative assessment and management 2018 Background: Pain is a multi-dimensional experience requiring an interdisciplinary approach. Barriers in pain assessment and management are numerous, varied, and often not clearly identified. In fact, they are challenging and resistant change. In this study, the contribution of human sciences with an aim to understand pain is explored. Humanistic models acknowledge the influence of an individual's personal experiences and concur that these experiences play a vital catalytic role in changing one's attitude and behavior, thus leading to a greater sense of well-being. Aim: The aim is to explore how the nursing staff's personal postoperative experience influences their behavior in assessing and managing a patient's pain postoperatively in Greece. Methods: A qualitative Interpretative Phenomenological Analysis (IPA) with an in-depth idiographic design was adopted for this study. Purposive sampling was employed to select 13 nurses who had at least two yearsâ professional experience in surgical wards and have had a previous personal experience of post-operative pain. Observations and semistructured interviews were undertaken to collect the data. The current study was conducted in Greece from May 2014 to September 2014. The analysis followed very closely the stages described in detail in IPA. Results: All the participants had experienced intense post-operative pain which was inadequately assessed and managed. Observation and interview analysis showed that this experience influenced their attitude, beliefs, and behavior. Participants become more sensitive, empathetic, attentive and understanding of their patient's post-operative pain because of their own person experience. Participants were able to assess and manage their patientsâ post-operative pain effectively even when they had no previous knowledge of pain assessment tools. Conclusions: The participantsâ personal postoperative experience changed their behavior towards patientsâ postoperative pain assessment and management. It became the driving force for them to discern the conflict powers that raised obstacles to apply a personcentered therapeutic approach. The novelty of the current research lies in the fact that it constitutes the first research that has been conducted in Greece combining IPA, Rogers and Lewin's theory.