W J Hamel explored the effects of music therapy on the anxiety levels, heart rate and blood pressure of patients waiting for their scheduled cardiac catheterization. 101 (63 men and 38 women) patients were randomly assigned to listen to 20 minutes of pre-selected music or to a standard care control group. Measurements were taken during the waiting period and just prior to departure for the lab. The intervention group had a significant reduction in anxiety (p = 0.003) and when compared to the controls (p = 0.004). Where the heart rate and systolic blood pressure dropped in the music therapy group, it increased in the control group. This held up whether the patient was male or female, but the men as a group had higher diastolic scores than the women, and the women had higher anxiety scores than the men.