deletions | additions       diff --git a/subsection_Indirect_estimates_When_there__.tex b/subsection_Indirect_estimates_When_there__.tex  index 836ad32..85ee6f9 100644  --- a/subsection_Indirect_estimates_When_there__.tex  +++ b/subsection_Indirect_estimates_When_there__.tex 
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$P = \sum I_{i,j} d_{i,j}, i \in \lbrace 1, 2\rbrace, j \in \lbrace 1, 2\rbrace$  where the index variable $i$ denotes HIV+ and HIV–, the index variable $j$ denotes notified and non-notified cases, $d$ denotes the duration of disease in notified cases and $I$ is total incidence. In the absence of measurements, we did not allow duration in notified cases to vary among countries. Given their underlying uncertainty, prevalence estimates should be used with great caution in the absence of direct measurements from a prevalence survey. Unless measurements were available from national programmes (for example, Turkey), assumptions of the duration of disease were used as shown in Table 1. \ref{tab:duration}.  Scarce empirical data on disease duration (of note, a typically large proportion of bacteriologically confirmed cases detected during TB prevalence surveys did not report symptoms suggestive of TB at the time of survey investigations). An important limitation is that duration is considered constant within case categories for all settings and over time.