Table 1

Mycobacterium tuberculosis contact score

VariableWeight assigned
Relationship to TB index case
    No known TB contact0
    Non-household TB contact1
    Relative/other contact in household with TB2
    Secondary caregiver (care provider during day) in household with TB3
    Primary caregiver in household with TB4
Infectivity of TB index case
    No known TB contact0
    Sputum acid-fast negative2
    Sputum acid-fast positive4
Type of exposure to TB index case
    No known exposure0
    Lives and sleeps in different house1
    Lives and sleeps in same house2
    Sleeps in same room3
Duration (total hours) average contact per day with TB index case
    No known contact0
    0–3 h1
    4–7 h2
    8–11 h3
    ⩾12 h4
Total contact score (maximum = 15)
  • TB, tuberculosis.