Data restricted to† | IRR due to an additional mean daily hour of sunlight | IRR due to an additional mean daily hour of sunlight compared with the previous month |
---|---|---|
Entire year (not adjusted) | 1.018 (1.012 to 1.024)*** | 1.014 (1.007 to 1.022)*** |
Entire year (seasonality adjusted) | 0.995 (0.984 to 1.007)‡§ | 1.005 (0.996 to 1.015)¶,†† |
January | 1.014 (0.950 to 1.083) | 1.018 (0.969 to 1.069) |
February | 1.013 (0.968 to 1.061) | 1.001 (0.957 to 1.048) |
March | 0.982 (0.945 to 1.020) | 0.996 (0.966 to 1.026) |
April | 0.978 (0.939 to 1.020) | 1.012 (0.981 to 1.045) |
May | 1.010 (0.977 to 1.043) | 1.003 (0.978 to 1.028) |
June | 0.989 (0.959 to 1.021) | 0.996 (0.972 to 1.020) |
July | 0.992 (0.953 to 1.033) | 1.021 (0.995 to 1.048)++ |
August | 0.983 (0.948 to 1.018) | 0.988 (0.959 to 1.018) |
September | 1.006 (0.961 to 1.052) | 1.028 (0.993 to 1.064)++ |
October | 0.980 (0.923 to 1.041) | 0.986 (0.952 to 1.021) |
November | 0.978 (0.907 to 1.054) | 0.999 (0.954 to 1.047) |
December | 0.979 (0.922 to 1.040) | 1.002 (0.954 to 1.052) |
++p<0.20 +p<0.10 *p<0.05 **p<0.01 ***p<0.001.
†Data from Australia were recoded to align with Greece and Norway (eg, January became July, February became August, and so on).
‡p Value=0.44 for testing if sunlight variable could be removed without impacting the model (likelihood ratio test of cohort+year+sex+sun+month vs cohort+year+sex+month).
§p Value <0.001 for testing if all month variables could be removed without impacting the model (likelihood ratio test of cohort+year+sex+sun+month vs cohort+year+sex+sun).
¶p Value=0.25 for testing if sunlight variable could be removed without impacting the model (likelihood ratio test of cohort+year+sex+sun change+month vs cohort+year+sex+month).
††p Value <0.001 for testing if all month variables could be removed without impacting the model (likelihood ratio test of cohort+year+sex+sun change+month vs cohort+year+sex+sun change).