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Table 2 Baseline covariates

From: An exploration of the missing data mechanism in an Internet based smoking cessation trial

Covariate Parameter Type Smoking related? Description Summary statistics
Treatment β 1,1 Binary No Indicator for treatment group 877/1758 treated
Age β 1,2 Continuous No Age in years 38 (11)
Sex β 1,3 Binary No Indicator for a female participant 1126/1758 female
Qualifications β 1,4 Categorical No Educational qualifications: 1=None; 2=GCSE 3.06 (1.16)
     3=A-level; 4=Undergraduate Degree; 5=Postgraduate Degree  
Deprivation β 1,5 Categorical No Deprivation score, range 0-5, higher indicates more deprived 1.21 (1.09)
Conscientiousness β 1,6 Continuous No Conscientiousness score, range 1-5, higher 3.31 (0.84)
     indicates more conscientiousness (takes values between 1-5, in steps of 0.25, and so is not truly continuous).  
Determination β 1,7 Categorical Yes Determination to quit: 1=not at all; 5=extremely 4.30 (0.75)
Support β 1,8 Categorical Yes Does the participant feel supported by family and friends: 1=not at all; 5=extremely 3.31 (1.23)
Dependence β 1,9 Categorical Yes Cigarette dependence score, range 1-8, 5.48 (1.57)
     higher indicates greater dependence  
Previous β 1,10 Binary Yes Indicator for not having managed to quit previously 907/1758 have
  1. Summary statistics are shown where means and standard deviations (in parentheses) are given for the continuous and categorical variables.