Box 4 | Advantages and disadvantages of simultaneous comparisons

From the following article:

Evaluation of diagnostic tests for infectious diseases: general principles

Shabir Banoo, David Bell, Patrick Bossuyt, Alan Herring, David Mabey, Freddie Poole, Peter G Smith, N. Sriram, Chansuda Wongsrichanalai, Ralf Linke, Rick O'Brien, Mark Perkins, Jane Cunningham, Precious Matsoso, Carl Michael Nathanson, Piero Olliaro, Rosanna W. Peeling & Andy Ramsay

Nature Reviews Microbiology 5, S21-S31 (November 2007)

doi:10.1038/nrmicro1523

Advantages

  • Provide 'head to head' comparisons for two or more tests using a single reference standard and the same patient population
  • Speed: results are available sooner than if conducting sequential trials
  • More cost-effective

Disadvantages

  • Can be difficult to interpret results for several tests independently, as blinding is not usually possible (that is, the results of other tests on the same samples or individuals might be known to the testers)
  • Complicates the design of the evaluation, for example, randomization of the order in which specimens for the different tests are collected and assessed
  • Specimen quality can be compromised with increasing numbers of specimens collected, especially with specimens collected from limited anatomical sites, such as urethral swabs or finger-prick blood specimens
  • The collection of multiple specimens might not be acceptable to patients