Table 1.

Age and sex composition of the participants.

Group	N	Age Interval	Mean Age, yrs	N	Men Age, yrs	Mean	N	Women Age, yrs	Mean
Control	25	42–69	53.20	14	44–69	54.97	11	42–62	51.18
Grade 1	33	41–75	50.97	16	42–75	53.56	17	41–56	48.53
Grade 2	22	40–74	52.82	17	40–74	52.41	5	43–74	54.20
Total	80	40–75	52.18	47	40–75	53.51	33	41–74	50.27

The age and sex matches of the subgroups are close, except there are fewer female patients of Grade 2 group.