Table 1.
Variables evaluated in the logistic regression, their associated survey responses, and outcomes for the purpose of analysis
| Variable | Possible survey responses | Analytic expression |
|---|---|---|
| Age (as a continuous variable) | Chronological age by year | |
| Age (as a dichotomous variable) | Younger than 5 years = 0 | |
| Older than or equal to 5 years = 1 | ||
| Does initial index case or contact have TB (any known or suspected case)? | Yes | Yes = 1 |
| No | No = 0 | |
| Relationship of index case | No contact | Either no contact or known contact was not mother or other primary caregiver = 0 |
| Non-household contact | ||
| Household contact, but non-primary caregiver of patient | ||
| Primary caregiver other than the mother | Mother or another primary caregiver = 1 | |
| Mother | ||
| Proximity of contact with the child | No contact | No contact or known contact lives outside the house = 0 |
| Lives outside the patient’s home | ||
| Lives in the patient’s home | Lives in the same household = 1 | |
| Lives and sleeps in the same room? | ||
| Sleeps in the same bed? | ||
| Average time spent by the child with the contact daily* | No contact | No contact or known contact exposed to child less than 8 hours on average daily = 0 |
| 0–3 hours | ||
| 4–7 hours | ||
| 8–12 hours | 8 or more hours in contact on average daily = 1 | |
| ≥ 12 hours | ||
| Index case’s length of symptoms* | No contact | No contact or known contact with less than 12 weeks of symptoms = 0 |
| < 3 weeks | ||
| 4–7 weeks | ||
| 8–11 weeks | ||
| ≥ 12 weeks | Contact with 12 or more weeks of symptoms = 1 | |
| Did contact have TB smear-positive sputum? | Yes | Yes = 1 |
| No | No = 0 | |
| Were there six or more people in household pre-earthquake? | Yes | Yes = 1 |
| No | No = 0 | |
| Does child live in a municipality with high–TB-burden (prevalence > 7%)? | Yes | Yes = 1 |
| No | No = 0 | |
| Is patient displaced and living in shelter? | Yes | Yes = 1 |
| No | No = 0 | |
| If the child’s family is displaced, then does shelter have more than 25 cohabitants? | Yes | Yes = 1 |
| No | No = 0 | |
| Does anyone in the house smoke? | Yes | Yes = 1 |
| No | No = 0 | |
| Does the child’s family use wood or coal for cooking fuel? | Yes | Yes = 1 |
| No | No = 0 | |
| Does the child live in geographically isolated area (i.e., is their barangay of residence on an island)? | Yes | Yes = 1 |
| No | No = 0 |
TB = tuberculosis.
*
Survey responses were categorized dichotomously for analysis. The natural distribution of the data informed the chosen cut-points of 8 hours and 12 weeks.