Table 1.
Definitions used in the study based on variables recorded within ETR.Net and classified according to the WHO reporting framework.
| Variable | Categories | Definition |
|---|---|---|
| Previous TB treatment history | Newly treated | Patients who had no reported previous TB treatment or had received less than 4 weeks of TB treatment at any stage |
| Retreatment | Patients who received more than 4 weeks of anti-tuberculosis treatment previously, regardless of the time since the previous episode | |
| Site of disease | Pulmonary TB | Site of disease included any pulmonary involvement |
| Extrapulmonary TB | Site of disease exclusively affecting any organ other than the lung parenchyma | |
| Extent of diseasea | Disseminated | ICD10 codes for TB meningitis or miliary TB were combined |
| Not disseminated | All other ICD10 codes | |
| HIV statusb | HIV-positive | Determined using HIV test results, CD4 results, documentation of co-trimoxazole preventive therapy or use of ART. ART use does not include date of starting ART and cannot differentiate ART before TB or those started on ART during TB treatment |
| HIV-negative | Documented negative results in TB treatment register | |
| HIV unknown | HIV status unable to be determined from results or inference | |
| Outcome 1c | Success | Cured or treatment completed |
| Died | Death due to any cause during the TB treatment episode | |
| Lost-to-follow-up | Patients who interrupted TB treatment for 2 consecutive months or patients where a treatment outcome is not allocated and an outcome of ‘not evaluated’ was recorded in ETR.Net | |
| Failed | Patients who were microbiologically positive at the start of treatment and remain or become positive after at least 5 months of TB treatment | |
| Drug resistance | Patient diagnosed with drug resistance after 12 weeks of TB treatment | |
| Transferred out | Patient who was referred to a facility in another district and the final TB treatment outcome is not known | |
| Outcome 2 | Favourable | Patients successfully treated for TB (cured or completed) |
| Unfavourable | A combined definition of all negative outcomes including died, lost-to-follow-up, failed, drug resistance, or transferred out | |
| Outcome 3 | Dead | Death due to any cause during the TB treatment episode |
| Alive | Patients who were known not to have died at the end of TB treatment including success, failed or drug resistance. This excludes patients who were lost-to-follow-up or transferred out where mortality is not known |
ART: antiretroviral therapy; ETR.Net: Electronic tuberculosis register; ICD10: International classification of disease 10; TB: tuberculosis.
aExtent of disease could only be ascertained where an ICD10 code was documented.
bHIV status is typically recorded at the start of TB treatment but may be updated during TB treatment.
cOutcomes are assigned by routine treating clinicians and ETR.Net includes pre-programmed algorithms to verify outcomes consistent with WHO and National Department of Health definitions.