The following contains some variable definitions for clarity. Please
see text in paper for definition of all the variables.
Education
  1 = none
  2 = some primary
  3 = end primary
  4 = some secondary
  5 = end secondary
  6 = some tertiary
  7 = tertiary
Income (monthly)
  1 = no income
  2 = less than R500
  3 = 501 to 1000
  4 = 1001 to 2000
  5 = 2001 to 4000
  6 = 4001 to 8000
  7 = 8001 to 16000
  8 = 16001 to 32000
  9 = more than 32000
D.general = DOSPERT-general
D.health = DOSPERT-health
D.nonhealth = DOSPERT-nonhealth
D.health.xsmoke = DOSPERT-health minus smoking
D.health.xdrink = DOSPERT-health minus drinking
D.health.xbelt = DOSPERT-health minus seat belt
D.health.xcondom = DOSPERT-health minus condom