title: A systematic review of economic models used to assess the cost-effectiveness of strategies for identifying latent tuberculosis in high-risk groups.
abstract: Timely diagnosis and treatment of latent tuberculosis infection (LTBI) through screening remains a key public health priority. Although globally it is recommended to screen people at high risk of developing TB, the economic evidence underpinning these recommendations is limited. This review critically appraised studies that had used a decision-analytical modelling framework to estimate the cost-effectiveness of interferon gamma release assays (IGRAs) compared to tuberculin skin test (TST) for detecting LTBI in high risk populations.
  
  
  
  A comprehensive search of MEDLINE, EMBASE, NHS-EED was undertaken from 2009 up to June 2015. Studies were screened and extracted by independent reviewers. The study quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) and the Philips' checklist, respectively. A narrative synthesis of the included studies was undertaken.
  
  
  
  Ten studies were included in this review. Two economic evaluations were conducted in a child population, six in an immunocompromised population and two in a recently arrived population from a country with a high incidence of TB. Most studies (n = 7) used a decision tree structure with Markov nodes. In general, all models were clearly described in terms of reporting quality, but were subject to limitations to structure and model inputs. Models have not elaborated on their setting or the perspective of the studies was not consistent with their analyses. Other concerns were related to derivation of prevalence, test accuracy and transition probabilities.
  
  
  
  Current methods available highlight limitations in the clinical effectiveness literature, model structures and assumptions, which impact on the robustness of the cost-effectiveness results. These models available are useful, but limited on the information that can be used to inform on future cost-effectiveness analysis. Until consideration is given on deriving the performance of tests used to identify LTBI that progresses to active TB, and the development of more comprehensive models, the economic benefit of LTBI testing with TST/IGRAs in high risk populations will remain unanswered.
authors.affiliation: Warwick Evidence, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, United Kingdom. Electronic address: p.auguste@warwick.ac.uk.
authors.forename: Peter
authors.initials: P
authors.lastname: Auguste
authors.affiliation: Evidence in Communicable Disease Epidemiology and Control, Health Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, United Kingdom.
authors.forename: Alexander
authors.initials: A
authors.lastname: Tsertsvadze
authors.affiliation: Warwick Evidence, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, United Kingdom.
authors.forename: Rachel
authors.initials: R
authors.lastname: Court
authors.affiliation: Warwick Evidence, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, United Kingdom.
authors.forename: Joshua
authors.initials: J
authors.lastname: Pink
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001431:Bacteriological Techniques / Q000191:economics*; D002648:Child; D002675:Child, Preschool; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D003663:Decision Trees; D054242:Emigrants and Immigrants; D017048:Health Care Costs; D006801:Humans; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000009:adverse effects; D015994:Incidence; D007223:Infant; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000191:economics* / Q000453:epidemiology / Q000276:immunology; D008390:Markov Chains; D008403:Mass Screening / Q000191:economics*; D008875:Middle Aged; D018803:Models, Economic; D011237:Predictive Value of Tests; D015995:Prevalence; D011379:Prognosis; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents
keywords: Cost-effectiveness; Decision-analytical modelling; Latent tuberculosis; Systematic review