Measurement properties of the calendar of premenstrual experience in patients with premenstrual syndrome.

OBJECTIVE

To assess the reliability and factor structure of the Calendar of Premenstrual Experiences (COPE) in premenstrual syndrome (PMS) patients.

STUDY DESIGN

Healthy women diagnosed with PMS (N = 215) completed daily diaries assessing 22 PMS behavioral and physical symptoms over two consecutive months.

RESULTS

Internal consistency (alpha) was high (.93-.94) for the COPE total score and behavioral subscale score and moderately high (.79) for the physical subscale score. Test-retest correlations produced lower estimates of reliability (.55-.59). Four factors, accounting for 64% of the total variance, were extracted: mood symptoms, somatic/cognitive symptoms, appetitive symptoms and fluid retention symptoms. Symptom reports increased in consecutive luteal phases for three of the four factors; however, the factor structure remained consistent in consecutive months.

CONCLUSION

The COPE diary is a reliable instrument for identifying fluctuations in behavioral and physical symptoms during the luteal phase, and PMS symptoms can be reliably conceptualized within four factors. Symptom expression may increase in response to daily self-monitoring.