Objective: The study was performed to determine the effect of self-efficacy on drug compliance and quality of life (QoL) in patients undergoing open heart surgery.

Materials and Methods: This descriptive and cross-sectional study included 132 patients who had previously undergone open cardiac surgery. The data were collected using the personal information form, Barnason Efficacy Expectation Scale (BEES) Cardiac Surgery Version, Morisky 8-item Medication Adherence Questionnaire (MMAS-8) and SF-36. Descriptive statistics, Mann Whitney U test, Kruskal Wallis test and Spearman's correlation analyse were used to analyze the data.

Results: The mean scores of the scales were BEES:43.50±5.90, MMAS-8: 5.32±1.90, SF-36 physical summary score: 36.40±9.54 and SF-36 mental summary score: 37.74±9.20. It was determined that the patients received scores the highest self-care (13.00±2.16) and the lowest physical (8.00±1.41) from BEES sub-scales. The highest and lowest mean subscale scores obtained from the SF-36 was from the subscales of pain (65.09±25.46) and physical role limitations (21.78±31.25) respectively. There was no correlation between self efficacy level and drug compliance, but there was a significant correlation between QoL (p<0.05).The BEES scores increased while the SF-36 physical and mental summary scores increased.

Conclusion: As a result of the study, As a result of the study, it was determined that patients the level of self efficacy was moderate, the drug compliances were low and the QoL was poor. It is thought that it would be beneficial to give continuous education and counseling services to increase the self-efficacy levels, drug compliance, and QoL of patients.