Proportional yields. (a) Proportions of prevalent TB cases are denoted as PYss, PYsc, PYxs and PYxc by TB symptoms and smear statuses where the total sum is 100% (Table 1). (b) Proportional yields based on the TB prevalence survey in Viet Nam.7 (c) Based on the TB prevalence survey in Cambodia.4 (d) Calculated by assuming that 40% of prevalent TB cases can be identified through symptomatic screening, 60% of TB cases are smear- positive and they are independently distributed. Note their similarity with (b).
Nishikiori and Van Weezenbeek BMC Public Health 2013 13:97 doi:10.1186/1471-2458-13-97