Method

Summary

A sample of children who had abused solvents was identified by means of a self-completed screening questionnaire that was administered to the third, fourth and fifth year pupils (ages 13 to 16 years) at sixteen secondary schools.

At each school, a sample of those who acknowledged that they had inhaled solvents to the point of intoxication at any time in the past were selected for individual assessment. For each case, a control who denied sniffing on the questionnaire was also selected. The controls were selected from the same schools as the cases and were individually matched for school year and sex.

The individual assessments consisted of a short interview, a breath test and an extensive battery of psychological tests.

The purpose of the interview was to validate the child’s questionnaire responses, to obtain detailed information on the frequency and pattern of solvent abuse, and to collect information on background socio-demographic and other factors that might be expected to affect psychological test performance.

The aim of the breath test was to identify children who might have been under the influence of solvents (or alcohol) at the time of psychological testing.

The battery of neuropsychological tests was designed to assess a range of functions implicated in previous studies of (a) chronic solvent abuse or occupational exposure to solvents, or (b) other CNS exposures, such as alcohol abuse in adults or severe head injury or meningitis in children and adolescents. It included measures of general intellectual and reading ability as well as tests to assess more specific functions such as psychomotor speed, attention, memory, manual and digital dexterity, and vibration perception.

In order to permit longitudinal comparisons with test results prior to solvent abuse, the schools were asked to provide details of the results of any standardized educational tests that had been taken by the cases and controls at or before the time of transfer from primary to secondary school.

During the following school year, follow-up assessments were conducted in order to provide longitudinal data on the practice of solvent abuse, to examine the stability of the psychological test findings from the initial assessment and to supplement the range of measures used at the initial assessment. Children who had been individually assessed and who were still at school were retraced and reexamined on questionnaires and a similar battery of psychological tests.