(a).

Ranks
	Age	N	Mean rank
Total pain score	40–59	17	23,62
	60–75	20	29,70
	76–97	19	31,61
	Total	56
Stage 1	40–59	17	30,56
	60–75	20	28,50
	76–97	19	26,66
	Total	56
Stage 2	40–59	17	21,32
	60–75	20	31,18
	76–97	19	32,11
	Total	56
Stage 3	40–59	17	24,79
	60–75	20	30,00
	76–97	19	30,24
	Total	56

N: number.