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Ethical approval for this research was gained from the Ethical and Research Committee of the Faculty of Nursing, Menoufia University (\n                      Approval number: ERCNMA 1000\/4\/1\/193\/26\n                      ). Official permission was obtained from the dean of the faculty of nursing to run the study after clarifying the purpose of the study. The study\u2019s purpose, procedures, potential risks, and benefits were explained to participants, and informed consent was gained before their involvement. Anonymity and confidentiality of the subjects\u2019 data (use code for patient name, all data stored in a safe location, and only shared with authorized personnel). Also, the participants were informed that participation in this study is voluntary; they have the right to choose to participate in the study and the right to withdraw from the study at any time. Because the study involved partial disclosure regarding the caffeine content of the beverage, this procedure was included in the approved protocol, and all participants were fully debriefed immediately after completing the study tasks. All methods in this study were implemented in accordance with the institutional research committee\u2019s ethical standards, as well as the Helsinki Statement [\n                      \n                      ]. 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