/*

Parental periconceptional smoking and 
male: female ratio of newborn infants

Misao Fukuda Kiyomi Fukuda, Takashi Shimizu,
Claus Yding Andersen, Anne Grete Byskov

Lancet 2002; 359: 1407Ð08

*/


DATA sexratio;
INPUT mother father  boys  girls;
total = boys + girls;
fa_lite  = (father=10); mo_lite   = (mother=10);
fa_heavy = (father=25); mo_heavy  = (mother=25);
LINES;
        0       0    1975  1627
        0      10     577   559
        0      25    2864  2911
       10       0      54    51
       10      10      40    39
       10      25     214   225
       25       0      41    47
       25      10      12    14
       25      25     255   310
;
RUN;

PROC LOGISTIC DATA = sexratio  ;
  MODEL boys/total = fa_lite fa_heavy   / rl corrb lackfit;
RUN;

PROC LOGISTIC DATA = sexratio  ;
  MODEL boys/total = mo_lite mo_heavy   / rl corrb lackfit;
RUN;

PROC LOGISTIC DATA = sexratio  ;
  MODEL boys/total = fa_lite fa_heavy mo_lite mo_heavy / rl corrb lackfit;
RUN;

PROC LOGISTIC DATA = sexratio  ;
  MODEL boys/total = father mother / rl corrb lackfit;
RUN;