A Differential Approach to Microcomputer Test Battery Development and Implementation

Abstract

The Automated Performance Test System (APTS), a microcomputer-based performance test battery, has been under development for over five years. The emphasis has been on psychometric theory and utility for repeated-measures applications during extended exposure to various environmental stressors. Stability of means and variances and retest reliability have been the criteria for suitability of a test. In addition, differential stability (i.e., parallelism of individual differences over sessions) is a unique requirement for test acceptability in this battery. In the present menu of “qualified” mental tests, there are presently more than 30 fully up-and-running on portable Zenith and NEC microcomputers as well as floppy disks for IBM compatible systems. Qualified tests stabilize in less than 10 minutes and possess test-retest reliabilities of r 0.70 for a three-minute test/work period. The battery includes tests of cognition, information processing, psychomotor skill, memory, mood, and others. More than a dozen normative laboratory and field studies have been conducted to validate the stability and reliability requirements of the tests in the battery and more than a dozen “sensitivity” studies have been or are in the process of being completed. To date, one or more tests have been shown sensitive to chemoradiotherapy, sleep loss, hypoxia, amphetamine, hyoscine, mood disorders, thermal stress, sensory deprivation, motion stress, altitude, fatigue, and alcohol use. The present paper describes our experiences with these tests and reports on a recommended menu for a short battery (6 minutes), a middle length battery (12 minutes), and a longer battery (22 minutes). Other test batteries which are presently under development do not pay as much attention to individual differences. The consequence of this inattention is low sensitivity if test-retest reliability is poor and inability to properly attribute effects if instability occurs.