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A C Bittner

Publications and source records attributed to A C Bittner.

9 recordsLinked to original sources
PubMed1985

Performance evaluation tests for environmental research (PETER): code substitution test.

The effects of repeated testing on code substitution performance were studied in three experiments to determine reliability and stability of task performance under laboratory and at-sea conditions. In Exp. 1, a single 2-min. testing trial per day was administered to a group of 19 subjects for 15 consecutive weekdays. In the second experiment a 4-min. per-day test was administered to 12 of the 19 original subjects for an additional 15 consecutive weekdays. In Exp. 3, six US Coast Guardsmen were tested hourly for four consecutive days, two days at dockside and two days at sea. In Exps. 1 and 2, means, variances, and cross-session correlations became stable after Day 8. Stabilized reliabilities were .75 for Exp. 1 and .80 for Exp. 2. The results of Exp. 3 were comparable to those obtained in the first two experiments with the exception that decrements in performance corresponding to high frequencies of motion sickness symptoms occurred during the at-sea trials. The Code Substitution Test is recommended for inclusion in the PETER battery.

Adult↗
PubMed1983

Performance Evaluation Tests for Environmental Research (PETER): Moran and computer batteries.

This investigation was directed at evaluating nine cognitive ability tasks for repeated measures applications and inclusion in the Performance Evaluation Tests for Environmental Research (PETER) battery. In the first study, five tasks from the Moran Battery, which were adapted from the French kit of factor-referenced tests, were administered to 18 subjects daily for 13 workdays. In the second study, four tasks from the Carter and Sbisa Computer Generated Battery were administered daily to 17 subjects (12 in common with first study) for 15 workdays. Examination of the means, variances, and interday reliabilities, together with factor analysis of the cross-task correlations, led to the recommendation of four tasks. Tasks recommended for repeated measures applications were Vertical Addition, Perceptual Speed, Grammatical Reasoning, and Flexibility of Closure.

Adult↗
PubMed1982

Television computer games: a 'new look' in performance testing.

Work at the Naval Biodynamics Laboratory aims at developing a battery of performance evaluation tests for environmental research (PETER). Because repeated-measures designs are virtually universal in environmental studies, the paradigm focuses on stabilisation with practice; thus far, over 50 tasks have been studied. The present report describes how five computerized video games fare as performance tests. The tasks were performed for 3 weeks each, in the same order, by the same subjects. The results show that four out of the five games meet all criteria satisfactorily and one does not, a favorable showing for the video games in comparison with conventional tests of either the paper-and-pencil or apparatus types. In terms of availability, equipment reliability, expense, and other practical considerations, the video games have many advantages. It is concluded that video games have considerable promise for performance testing and other applied contexts.

Adult↗
PubMed1980

Development of performance evaluation tests for environmental research (PETER): time estimation.

A time-estimation task was considered for inclusion in the Performance Evaluation Tests for Environmental Research (PETER) battery. As part of this consideration, the effects of repeated testing on the reliability of time judgments were studied. The method of production was used to estimate eight time intervals. Five trials per day at each interval were administered individually to each of 19 subjects for 15 consecutive workdays. Two scores, constant error and variable error, were reported. The effect of days was not significant for constant error and was moderate for variable error (p < .04). The standard deviations were relatively stable across trials. A pronounced decline in reliability over repeated days of testing was found for both errors. It was concluded that this time-estimation test would be a poor candidate for inclusion in PETER, but further research is warranted because of the potential unique contribution of a time-estimation task in a performance test battery.

Adult↗
PubMed1980

Development of performance evaluation tests for environmental research (PETER): complex counting test.

This study is the first in a program to develop a battery of Performance Evaluation Tests for Environmental Research (PETER). Nineteen volunteer subjects were tested daily for 3 weeks on a complex task requiring the operator to keep simultaneous track of several things with changing states. Average daily performances are reported as well as reliabilities of three main types: 1) internal consistency of the test; 2) sensitivity--the ability to differentiate subjects, and 3) stability--consistency of measurement over repeated sessions. The results showed that, on this task, learning was accomplished quickly, and performance stayed level for 3 weeks. The cross-tidal reliability for this test was found relatively stable after 3 d of practice, with a decline of only r=.94 to r=.79 over 11 d. This task is further noted as having several characteristics which make it particularly suitable for use in environmental research. It is concluded that the complex counting test can be recommended for use in environmental and other time-course research.

Adult↗
PubMedDate not supplied

Behavioral effects of low-level exposure to elemental Hg among dentists.

Exposure thresholds for health effects associated with elemental mercury (Hg degree) exposure were examined by comparing behavioral test scores of 19 exposed (mean urinary Hg = 36 micrograms/l) with those of 20 unexposed dentists. Thirty-six micrograms Hg/l is 7 times greater than the 5 micrograms Hg/l mean level measured in a national sample of dentists. To improve the distinction between recent and cumulative effects, the study also evaluated porphyrin concentrations in urine, which are correlated with renal Hg content (a measure of cumulative body burden). Subjects provided an on-site spot urine sample, were administered a 1-h assessment consisting of a consent form, the Profile of Mood Scales, a symptom and medical questionnaire, and 6 behavioral tests: digit-span, symbol-digit substitution, simple reaction time, the ability to switch between tasks, vocabulary, and the One Hole Test. Multivariate regression techniques were used to evaluate dose-effects controlling for the effects of age, race, gender and alcohol consumption. A dose-effect was considered statistically significant below a p value of 0.05. Significant urinary Hg dose-effects were found for poor mental concentration, emotional lability, somatosensory irritation, and mood scores. Individual tests evaluating cognitive and motor function changed in the expected directions but were not significantly associated with urinary Hg. However, the pooled sum of rank scores for combinations of tests within domains were significantly associated with urinary Hg, providing evidence of subtle preclinical changes in behavior associated with Hg exposure. Coproporphyrin, one of three urinary porphyrins altered by mercury exposure, was significantly associated with deficits in digit span and simple reaction time.(ABSTRACT TRUNCATED AT 250 WORDS)

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