Table
3: A metaanalysis
pooling odds ratios for cutaneous melanoma and dose information for continuous
or ordered categorical factors across casecontrol studies in populations of
Spanish descent based on a random effects model.
Linear DoseResponse Analyses^{a} 
Crude 
Heterogeneity 
Adjusted 
Heterogeneity 

N 
OR 
95% CI 
pvalue 
I^{2} 
OR 
95% CI 
pvalue 
I^{2} 

Skin Type  a difference of 
3 
0.016 
75.70% 
0.034 
70.40% 

1 (I vs. II, II vs. III, or III vs. IV) 
2.34 
2.002.75 
2.31 
1.952.74 

3 (I vs. IV) 
12.87 
7.9520.82 
12.35 
7.4320.51 

Lifetime sunburns  a difference of^{b} 
3 
0.01 
78.50% 
0.008 
79.30% 

1 burn per lifetime 
1.14 
1.111.18 
1.1 
1.071.14 

5 burns per lifetime 

1.95 
1.692.24 


1.62 
1.381.91 


CI =
Confidence interval, N = Number of subjects, OR = Odds ratios, vs = versus.
^{a}A
linear model estimates an increase of one unit, but can be set to specific
units while remaining the same model. We present a difference that is
meaningful for a given factor.
^{b}An
upper limit of the number of sunburns was estimated from which the median of
the upper category for each