TABLE 4.

Discriminant validity of the Menstrual Bleeding Questionnaire

	Reported problem with uterine bleeding			p-value
	None (n=88)	Irregular only (n=20)	Heavy +/− Irregular (n=36)	None vs. Irregular	None vs. Heavy
Total MBQ 20 items
Mean (SD)	10.6 (8.6)	12.7 (9.5)	30.8 (14.0)	0.4	<0.0001
IQR	4.0 – 15.5	4.0 – 19.5	23.0 – 37.5
Bleeding heaviness 8 items
Mean (SD)	5.6 (4.4)	6.2 (4.1)	13.1 (5.7)	0.7	<0.0001
IQR	2.0 – 7.5	2.5 – 9.5	10.0 – 15.0
Bleeding irregularity 3 items
Mean (SD)	3.3 (1.8)	3.9 (1.8)	4.4 (1.4)	0.2	0.002
IQR	2.0 – 5.0	2.0 – 6.0	3.5 – 6.0
Pain 1 items
Mean (SD)	1.5 (0.9)	1.8 (1.0)	2.1 (0.8)	0.4	0.004
IQR	1.0 – 2.0	1.0 – 2.5	2.0 – 3.0
Quality of life 8 items
Mean (SD)	3.5 (4.6)	4.2 (5.0)	13.3 (7.6)	0.5	<0.0001
IQR	0 – 6.0	0 – 9.0	7.5 – 20.0