Diagnostic validity of hospital discharge codes in the ascertainment of amyotrophic lateral sclerosis.

摘要

In a recent publication, Pisa et al. [1] assessed the validity of hospital discharge data as a method of identifying cases of amyotrophic lateral sclerosis (ALS). After a review of hospital charts from 511 patients, they concluded that a discharge code for ALS had a sensitivity of 93% and a specificity of 99% for the diagnosis of ALS. A detailed exam of the study design, however, suggests that sensitivity and specificity could not be adequately estimated. Sensitivity of a diagnostic test can be defined as the probability that a diseased person in the population tested will be identified as diseased by the test [2].