Table 3. Comparison of changes in mean premenstrual syndrome scores before and after the intervention in two groups.

Characteristics	Calcium group (n=32)	Placebo group (n=32)	P-value
On admission (cycle 0)
Anxiety	2.34 (0.90)	1.18 (0.85)	0.595
Depression	2.16 (0.95)	1.75 (0.71)	0.052
Emotional	1.88 (1.02)	1.56 (0.66)	0.143
Water retention	1.81 (1.23)	1.06 (0.66)	0.102
Somatic changes	2.41 (1.07)	2.22 (0.55)	0.383
One month later (cycle 1)
Anxiety	1.84 (0.98)	1.50 (0.88)	0.020
Depression	1.47 (0.91)	1.81 (0.59)	0.001
Emotional	1.41 (0.79)	1.38 (0.87)	0.037
Water retention	1.22 (1.03)	0.84 (0.76)	0.004
Somatic changes	1.72 (1.05)	0.46 (1.91)	0.045
Two months later (cycle 2)
Anxiety	1.28 (0.85)	1.75 (0.80)	0.001
Depression	1.09 (0.92)	2.00 (0.67)	0.001
Emotional	0.94 (0.87)	1.28 (0.77)	0.032
Water retention	0.95 (0.94)	1.29 (0.67)	0.032
Somatic changes	1.31 (0.93)	2.41 (0.56)	0.001

Values are presented as mean (standard deviation).