Table 2

Comparison of MDR-TB outcome measures (simplified)

OutcomeLaserson et al. [20] (2005)WHO [23] (2014)TBNET [24] (2016)
DiedA patient who dies for any reason during the course of treatmentA patient who dies for any reason during the course of treatmentA patient who dies during the period of observation
LTFU/defaultA patient whose treatment was interrupted for 2 consecutive months or moreA patient whose treatment was interrupted for 2 consecutive months or moreNon-receipt of care 6 months after treatment initiation
Treatment failed≥2 of 5 cultures in the final 12 months of treatment are culture positive or if any of the final 3 cultures are positive
OR
a clinical decision is made to stop treatment due to a lack of response
Treatment terminated or need for permanent regimen change of at least two anti-TB drugs because of
 lack of conversion by the end of the intensive phase
 bacteriological reversion in the continuation phase after conversion to negative
 evidence of additional acquired resistance to fluoroquinolones or second-line injectable drugs
 adverse drug reactions
A positive culture 6 months after the start of treatment or a relapse within 1 year after treatment completion
Completed treatmentCompleted treatment but does not meet the definition of cureTreatment completed as recommended by the national policy without evidence of failure BUT no record that ≥3 consecutive cultures taken ≥30 days apart are negative after the intensive phaseUnacceptable: a measure of process and not treatment outcome
CuredCompleted treatment according to protocol with ≥5 negative cultures in the last 12 months or 1 positive culture with 3 subsequent cultures taken ≥30 days apartTreatment completed as recommended by the national policy without evidence of failure AND record that ≥3 consecutive cultures taken ≥30 days apart are negative after the intensive phaseA negative culture status at 6 months after the start of treatment and no positive culture thereafter AND no relapses within 1 year after treatment completion
Treatment successThe sum of cured and treatment completedNot applicable
UndeclaredTransfer out included as a separate elementA patient for whom no treatment outcome is assigned (this includes “transferred out” where outcome unknown)Outcome not assessed due to
 transferred out and no outcome known
 no culture at 6 months
 no post-treatment assessment
Timing36 months after treatment started
Interim analyses at 12 and/or 24 months
≤12 months (included in annual report)
36 months outcome after treatment started
6 months into treatment and 12 months after treatment completion (most often 32 months after treatment started)

LTFU: lost to follow-up.