Table 5.

Odds Ratios and 95% Confidence Intervals for Associations of Melanoma With Selected Known Risk Factors, for Different Control Groups, Australian Melanoma Family Study, 2001–2005

Risk Factor	No. of Cases	Total Controls (Population and Spouse/Friend)			Population Controls			Spouse/Friend Controls			Sibling Controls				Meta-Analysisa
		No.	Odds Ratiob	95% Confidence Interval	No.	Odds Ratiob	95% Confidence Interval	No.	Odds Ratiob	95% Confidence Interval	No. of Casesc	No. of Controls	Odds Ratiod	95% Confidence Interval	Odds Ratio	95% Confidence Interval
Hair color
Dark brown/black	157	189	1.00		97	1.00		92	1.00		109	224	1.00		1.00
Light brown	243	207	1.26	0.94, 1.71	98	1.46	1.00, 2.13	109	1.11	0.76, 1.62	157	253	1.37	0.95, 1.97	1.62	1.11, 2.34
Fair or blonde	140	63	2.34	1.59, 3.44	26	3.22	1.91, 5.43	37	1.71	1.06, 2.78	88	118	1.85	1.13, 3.01	1.96	1.41, 2.74
Red	72	25	3.02	1.79, 5.11	12	3.20	1.60, 6.37	13	2.88	1.44, 5.74	42	67	1.61	0.91, 2.83	3.64	2.56, 5.37
Ptrend			<0.001			<0.001			<0.001				0.02
Ability to tan (repeated exposure)
Very brown and deep tan	84	119	1.00		63	1.00		56	1.00		50	123	1.00		1.00
Moderate tan	271	203	1.91	1.35, 2.72	92	2.11	1.37, 3.27	111	1.60	1.02, 2.49	179	293	1.69	1.09, 2.61	1.77	1.23, 2.56
Mild or occasional tan	179	116	2.00	1.35, 2.94	55	2.20	1.36, 3.56	61	1.60	0.98, 2.63	123	189	2.01	1.25, 3.22	1.84	1.43, 2.36
No tan or only freckles	75	43	2.11	1.29, 3.45	22	2.20	1.18, 4.09	21	1.91	1.00, 3.65	45	60	2.53	1.35, 4.74	2.09	1.67, 2.58
Ptrend			0.002			0.007			0.06				0.002
Mole count on back
None	33	59	1.00		31	1.00		28	1.00		22	77	1.00		1.00a
1–4	88	103	1.37	0.80, 2.33	44	1.56	0.80, 3.03	59	1.25	0.65, 2.39	51	124	1.52	0.80, 2.87	1.44	1.29, 1.60
5–10	137	127	1.62	0.97, 2.71	68	1.62	0.87, 3.01	59	1.79	0.95, 3.36	90	167	2.22	1.17, 4.19	2.48	1.90, 3.23
11–15	67	43	2.39	1.31, 4.35	23	2.41	1.15, 5.01	20	2.25	1.05, 4.82	41	78	1.94	0.95, 3.96	4.82	3.05, 7.62
≥16	263	133	2.87	1.74, 4.71	60	3.33	1.81, 6.16	73	2.53	1.38, 4.65	172	171	4.72	2.47, 9.00
Ptrend			<0.001			<0.001			<0.001				<0.001
Reported family history of melanoma in first-degree relative
None	525	442	1.00		214	1.00		228	1.00						1.00
≥1	97	46	1.98	1.34, 2.92	21	1.91	1.13, 3.22	25	1.96	1.19, 3.23					1.74	1.41, 2.14
P value			<0.001			0.02			0.008

^aResults from meta-analyses by Gandini et al. (24, 30). For mole count, the odds ratios from the meta-analysis are not directly comparable because they are based on mole count on arms (not on the back as in our study); however, we have used the same cutpoints, and a different pooled analysis (60) has shown similar risk estimates for mole counts on the trunk and upper limbs.

^bAnalyzed by using unconditional logistic regression. Adjusted for age, sex, state, ethnicity (Caucasian, other), reported family history (first degree) of melanoma (none, any), education (junior high school, senior high school, vocational, university), and lifetime cumulative time spent outdoors (quartiles). Excludes spouse controls aged ≥45 years (n = 33) and cases and controls missing values for any of the covariates (6 cases, 4 population controls, 3 spouse controls).

^cExcludes 222 cases with no sibling controls.

^dAnalyzed by using conditional logistic regression (matched by family). Adjusted for age, sex, education (junior high school, senior high school, vocational, university), and lifetime cumulative time spent outdoors (quartiles). Excludes sibling controls aged ≥45 years and cases and controls missing values for any of the covariates (5 cases; 11 sibling controls).