Table 1. Baseline characteristics of study participants (1984–2002).

	Person-years	Melanoma		Squamous cell carcinoma		Basal cell carcinoma
		Cases	Crude incidence ratea	Cases	Crude incidence ratea	Cases	Crude incidence rateb
Total	1 814 108	375	20.67	495	27.29	9423	519.43
Age (years, mean)b		58.54		61.40		63.73
Family history of melanoma
No	1 725 247	341	19.77	473	27.42	8746	506.94
Yes	88 861	34	38.26	22	24.76	677	761.86
Number of moles on left arm
0	793 854	138	17.38	251	31.62	4288	540.15
1–2	396 930	114	28.72	136	34.26	2571	647.72
3–5	31 859	19	59.64	14	43.94	243	762.74
≥6	23 958	15	62.61	11	45.91	180	751.31
Childhood/adolescent tanning ability
Good tan	334 653	49	14.64	79	23.61	1462	436.87
Average tan	631 873	136	21.52	175	27.70	3503	554.38
Little tan	305 274	93	30.46	121	39.64	2054	672.84
Almost none	119 761	37	30.89	53	44.25	849	708.91
Childhood/adolescent burn susceptibility
No burn	288 546	46	15.94	60	20.79	1072	371.52
Some redness	613 152	124	20.22	170	27.73	3247	529.56
Burn	306 377	90	29.38	129	42.10	2117	690.98
Painful burn	130 844	36	27.51	50	38.21	953	728.35
Painful burn with blisters	69 697	26	37.30	26	37.30	588	843.65
Natural hair color at age 20 years
Black	60 318	8	13.26	13	21.55	193	319.97
Dark brown	601 502	112	18.62	169	28.10	2966	493.10
Light brown	532 894	139	26.08	157	29.46	3170	594.87
Blonde	157 085	43	27.37	68	43.29	1172	746.09
Red	56 347	19	33.72	26	46.14	476	844.77

^amean age at time of diagnosis.

^bper 100 000 person-years.