The natural history of untreated pulmonary tuberculosis in adults: a systematic review and meta-analysis

Quantifying progression and regression across the spectrum of pulmonary tuberculosis: a data synthesis study

“…This review included prospective and retrospective studies that followed and recorded the disease state of individuals with tuberculosis in a cohort without treatment, and details have been published elsewhere. 14 Briefly, we searched PubMed, Embase, and Web of Science in English and German from the start of each database until 1960, alongside hand searches of the Index Medicus from 1903 to 1945. We supplemented these searches with articles from personal collections and snowballed references of all included studies with no date restrictions.…”

“…All studies were required to directly report microbiology or use standards that included microbiology in the definitions. 6 , 14 The first timepoint described the state of a baseline group, and the second (and further) timepoints described the states of a subgroup of individuals (those who had changed state) after a recorded time. 14 To enable synthesised analysis, two study types were included: cumulative and single follow-up studies.…”

“…6 , 14 The first timepoint described the state of a baseline group, and the second (and further) timepoints described the states of a subgroup of individuals (those who had changed state) after a recorded time. 14 To enable synthesised analysis, two study types were included: cumulative and single follow-up studies. In cumulative follow-up studies, individuals were closely followed up with cumulative recording of whether they had transitioned to a new state.…”

“… 9 , 15 We adjusted the cohort size for people starting with minimal disease using tuberculin skin tests as a proxy for radiographic changes that were truly caused by M tuberculosis infection ( appendix pp 22–23 ). Although the systematic review 14 collected data on whether radiographic findings were considered to indicate active or inactive disease, this distinction has not been carried forward ( appendix p 22 ).…”

“… 11 , 12 , 13 Our previous comprehensive review of literature identified many data sources, both historical and contemporary, that observed cohorts transitioning across the spectrum of disease. 14 However, no single study has provided an overview of all trajectories across the different states. Additionally, with studies having varying durations, follow-up structures, and approaches to define and report disease states, the resulting heterogeneity complicates a simple comprehensive analysis.…”