Skip to main content

Diagnosis and Control of Johne's Disease (2003) / Chapter Skim
Currently Skimming:

Appendix A: Interpretation of Diagnostic Results
Pages 175-178

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 175...
... A test result is often classified into a category, such as positive or negative. For bacterial culture, a positive test may be the appearance of colonies on the medium that has a colony morphology consistent with that of the bacteria of interest within the appropriate timeframe.
Read the entire page →
From page 176...
... In the case of a serologic test such as ELISA, the false positive result could occur because the animal responded to an antigen in their environment that is immunologically similar to the target antigen from Map that is used in the test. A negative test result can be a true negative or a false negative.
Read the entire page →
From page 177...
... Bayes Theorem relates predictive values and prevalence to sensitivity and specificity (Last, 1995~. Understanding these relationships is critical to making appropriate testing decisions, both in deciding which tests to employ and how to interpret positive and negative test results.
Read the entire page →
From page 178...
... Third, the appropriate gold standard, a definitive reference testing procedure with very high sensitivity and specificity, must be used to establish the infection status of the study animals. At present, the gold standard is necropsy followed by extensive culture and histological examination of multiple sections of lower small intestine and associated lymph nodes to reliably establish the infection status of each study animal.
Read the entire page →

Key Terms

  • test result
  • negative test
  • false positive
  • false negative
  • positive test

  • predictive value
  • cutoff value
  • comparing test
  • predictive values
  • positive result

  • immune response
  • true positive
  • true negative
  • clinical animals
  • test indicates

  • gold standard
  • infection status
  • bacterial culture
  • epidemiologic sensitivity
  • lymph node

  • positive predictive
  • target antigen
  • analytical sensitivity
  • conventional test
  • morphology consistent

  • fecal bacterial
  • testing procedure
  • infection prevalence
  • histological examination
  • immunologically similar


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.