Table 2.

Demographic characteristics of case and control groups in case-control study

	Cases	Controls	P value
Total number	31	97
Males, n (%)	23 (74%)	83 (86%)	0·17*
Officers, n (%)	9 (29%)	25 (26%)	0·65*
Age range (years)	20–62	20–62
Average age (years)	30·3	33·8	0·07†

^*χ² test.

^†t test.