DUMC Library: EBM Glossary - M - N

  • Meta-analysis
    A systematic review of the literature that uses quantitative methods to summarize the results.

  • N-of-1 trials
    In such trials, the patient undergoes pairs of treatment periods organized so that one period involves the use of the experimental treatment and the other involves the use of an alternate or placebo therapy. The patient and physicians are blinded, if possible, and outcomes are monitored. Treatment periods are replicated until the clinician and patient are convinced that the treatments are definitely different or definitely not different.

  • Negative predictive value
    Proportion of people with a negative test result who are free of the target disorder.

  • NNT -- see Number Needed to Treat

  • Number Needed to Treat (NNT)
    The number of patients that need to be treated with a specified therapy in order to prevent one additional bad outcome. Calculated as the inverse of the absolute risk reduction (1/ARR).

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    Last modified on: 16-Dec-04