Statistics for the clinician: diagnostic questionnaires.
The goal of this column is to help working clinicians understand the statistical calculations involved in interpreting the results of diagnostic questionnaires. Using the Patient Health Questionnaire-9 as an example, the author explains how to determine the most appropriate cutoffs to choose, depending on the population involved, the probabilities of error (a and {), and the expected losses associated with each kind of error in the context in which the test is being administered. (Journal of Psychiatric Practice. 2011;17:57-60).
Consulting mathematician and software developer in the Bioinformatics and Biostatistics Core Facility, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Switzerland.
Frederick J
FJ
Ross
D006801:Humans; D001523:Mental Disorders / Q000175:diagnosis*; D011336:Probability; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data*; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D011795:Surveys and Questionnaires