title: Proposals for a phased evaluation of medical tests.
abstract: BACKGROUND
  In drug development, a 4-phase hierarchical model for the clinical evaluation of new pharmaceuticals is well known. Several comparable phased evaluation schemes have been proposed for medical tests.
  
  
  OBJECTIVE
  To perform a systematic search of the literature, a synthesis, and a critical review of phased evaluation schemes for medical tests.
  
  
  METHODS
  Literature databases of Medline, Web of Science, and Embase.
  
  
  METHODS
  Two authors separately evaluated potentially eligible papers and independently extracted data.
  
  
  RESULTS
  We identified 19 schemes, published between 1978 and 2007. Despite their variability, these models show substantial similarity. Common phases are evaluations of technical efficacy, diagnostic accuracy, diagnostic thinking efficacy, therapeutic efficacy, patient outcome, and societal aspects.
  
  
  CONCLUSIONS
  The evaluation frameworks can be useful to distinguish between study types, but they cannot be seen as a necessary sequence of evaluations. The evaluation of tests is most likely not a linear but a cyclic and repetitive process.
authors: Department of Clinical Epidemiology & Biostatistics, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors: Jeroen G
authors: JG
authors: Lijmer
authors: Mariska
authors: M
authors: Leeflang
authors: Patrick M M
authors: PM
authors: Bossuyt
mesh_terms: D003933:Diagnosis; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D006801:Humans; D013677:Medical Laboratory Science / Q000592:standards*; D008962:Models, Theoretical