Effect of Stress Ball Application During Coronary Angiography on Anxiety, Procedure-related Fear, Physiological Parameters, and Comfort

Inclusion Criteria: * Aged 18 years or older, as verified by medical records and official identification. * Scheduled to undergo elective coronary angiography, as confirmed by the patient's medical records. * Conscious, oriented, and cooperative, as assessed by the researcher during the pre-procedural interview. * Able and willing to provide written informed consent after receiving information about the study. * Able to speak Turkish and understand and respond to the questions asked during the study. * No visual, hearing, or speech impairment that would interfere with communication. * No motor or sensory impairment of the hand or arm that would prevent the use of a stress ball, as assessed through patient self-report and clinical observation. * No diagnosed anxiety disorder and no self-reported history of receiving psychiatric treatment for anxiety. Exclusion Criteria: * Decline to participate or request to withdraw from the study at any stage. * Undergo emergency coronary angiography. * Have cognitive, communication, or physical impairments that prevent completion of the data collection instruments or participation in the study procedures. * Develop clinical complications during or after the procedure that preclude implementation of the study protocol.