Aims: The aim of this study was to evaluate the validity and reliability of the stress index for 10-18-years-old children or adolescents with Tourette syndrome.
Background: Tourette syndrome is a chronic tic disorder, which occurs in childhood. Children with Tourette syndrome exhibit sudden and unexpected voices or movements that may have influence on their daily activities and cause interaction barriers for children with Tourette syndrome. Therefore, a self-report stress index is necessary for children with Tourette syndrome to quickly measure the stress they have.
Design and methods: Eight experts rated appropriateness, comprehensiveness and relevance of the questionnaire to establish content validity. A total of 116 paediatric patients filled out the stress index for 10-18-years-old children or adolescents with Tourette syndrome to evaluate its construct validity using exploratory factor analysis and internal consistency. Data from 90 pairs of paediatric patients and their caregivers were used to evaluate the inter-rater reliability.
Result: The criterion validity index ranged from 80-98%. One item was deleted because of a small item-to-total correlation. Therefore, 26 items made up the final stress index for 10-18-years-old children or adolescents with Tourette syndrome. In exploratory factor analysis, four factors (unfairly treated, psychological, symptom control and future concern) were achieved and accounted for 52.3% of the total variance. Cronbach's alphas of the stress index for 10-18-years-old children or adolescents with Tourette syndrome were 0.89. The inter-rater reliability of stress Index for 10-18-years-old children or adolescents with Tourette syndrome (Pearson correlation coefficient between patients and their caregivers) was 0.56.
Conclusion: The stress Index for 10-18-years-old children or adolescents with Tourette syndrome is a self-administered tool to assess the stress of children or adolescents with Tourette syndrome. Validity (content and construct) and reliability (internal consistency and inter-rater reliability) of our Stress Index for 10-18-years-old Children or Adolescents with Tourette syndrome was acceptable.
Relevance to clinical practice: The Stress Index for Children or Adolescents with Tourette Syndrome appears to be an ideal instrument for evaluating the stress for children with Tourette syndrome in clinical setting and finding the direction in designing an appropriate intervention programme. We welcome other researchers to use stress index for 10-18-years-old children or adolescents with Tourette syndrome so that their findings can be compared using the same measurement.