Comparison of Scoring Methods for Tests of Attention, Including an Error Index for Use with Schizophrenic Patients

Abstract

A resumé is given of various doubts raised concerning the application of signal-detection theory to discrimination tasks involving ‘suprathreshold’ stimuli, as in tests of vigilance and selective attention. The validity of this theory in pathological conditions, such as schizophrenia, is also questioned. The continuing need for a unitary index combining errors of omission and commission is emphasized and the various indices so far proposed are compared using experimental data. A new Error Index is offered as a more satisfactory resolution.