Table 1.

Distribution of cases and controls by selected characteristics

CasesHospital controlsPopulation controlsP of log-likelihood ratio test*
No. subjects211211197
Men (%)66.459.762.9NS
Education (%)100100100
    Primary school6459.761.9NS
    Vocational and high school2.81.43.0
Occupation (%)100100100
    Agricultural workers71.670.173.3
    Service workers16.620.913.3
    Professional and clerical1.90.90.6NS
    Industry crafts and trade4.33.89.4
Smoking status (%)100100100
Years of regular smoking§
Average cigarettes/d§
%Smokers of manufactured cigarettes only
%Smokers consuming commercial cigarettes by age
Age (y)
    56-6432.329.229.9P < 0.01
%Regular chewers of miang
%Regular chewers of betel nut**
  • Abbreviation: NS, not significant.

  • * Test for independence of case/control status and variable on the row unless otherwise specified.

  • Includes street vendors.

  • P for the difference of the three proportions within group.

  • § Smokers excluded.

  • P for trend by age.

  • Mixture of fermented tea leaves, coconut, peanut, and sugar.

  • ** Betel nut, tobacco, red lime, and fresh leaf of piper betel.