FINAL REPORT: Validation of Test Methods for Assessing Neurodevelopment in Children¹

Historical Reference
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Preliminary Results

The project was conducted in two phases, starting in 1998. First, a pilot study² was conducted to develop the test battery and field-test it both in Rochester and in Seychelles. The current study then followed. A detailed report of the pilot study has been published (Davidson, et al., 2000), but for the sake of continuity, we will summarize the outcomes here. The test battery evaluated in the Seychelles, and shown in Table 1, includes measures of cognitive, motor and sensory functions adversely affected in animals and humans exposed to high levels of neurotoxicants.

All tests in Table 1 were developed and field-tested on 15 normal children in Rochester. They were then successfully transferred to the Seychelles and field-tested there to ascertain their portability and appeal to children from a non-US, non-English-speaking culture. Rochester team members administered the tests in the Ministry of Health’s Child Development Center at Victoria Hospital on Mahé Island. Each child was tested individually. A Creole-speaking Seychellois team member was present in each testing room at all times. In October 1998, 61 normal children from the Seychelles Child Development Study (SCDS) pilot cohort were administered one half of the test battery. The subjects’ age range was 10.5 to 11 with a mean age of 10.6 years. The remaining tasks were field tested in March 1999 in the Seychelles on 58 of the 61 children tested in October.

Table 1 Pilot Study Test Battery
Domain	Neuropsychological and Behavioral	Physiological	Experimental
Cognitive (C)	Tower of London Wisconsin Card Sorting K-BIT Matrices (Care-giver)	P-300 during CPT	Visual-Motor Learning Delayed Matching Repeated Acquisition
Auditory and Visual Information Processing (AV)
Visual	Visual system response	Pattern Reversal Evoked Potentials	Scotopic Form Discrimination; Spatial Contrast Sensitivity
Auditory	Pure Tone Audiogram Screening Test for Auditory Perceptual Disorders Test of Auditory Perceptual Skills Pitch Pattern Sequence Test Competing Environmental Sounds Test Dichotic Digit Test	Auditory Brainstem Response Potentials Otoacoustic Emissions
Fine Motor (FM)	Fine motor control		Coordination, Tremor and Positioning RT, MT
Somatosensory (SS)	Complex Form Matching		Spatial Contrast Skin Sensitivity
Perceptual-Motor (PM)	Alertness		Monitoring and Coordination multi-tasking

The preliminary data demonstrated that it was feasible to implement in the field, even in an environment such as the Seychelles, a highly complex battery of tabletop and computer-based physiological and behavioral measures. Very few problems were encountered in transporting and maintaining the sensitive equipment, or in assuring its proper operation in Seychelles. Those minor problems that did occur with the instrumentation were easily solved on site. The field test results also contributed to decisions about inclusion of tasks and tests in the final battery used in the present study.

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