The injury illness sensitivity index - Revised: Further validation in a Dutch community sample

Injury/illness sensitivity (IS) is conceptualized as a fundamental fear that underlies fear-related psychopathology and chronic health conditions, including chronic pain. The current study examines the internal consistency, test-retest reliability, and factor structure of the Dutch version of the injury/illness sensitivity index-revised (ISI-R). In addition, we aimed to further validate the ISI-R by studying convergent and divergent validity. Participants (N = 255) were recruited in a Dutch community sample to complete an online questionnaire battery including the ISI-R and several validation measures. Four weeks later, 117 participants completed the ISI-R a second time. The ISI-R showed good internal consistency and test-retest reliability. Confirmatory factor analysis confirmed two correlated factors in the ISI-R: Fear of Injury and Fear of Illness. The measure's validity was supported by strong correlations between the ISI-R and well-established pain and physical health-related anxiety measures, moderate correlations with measures that reflect general negative emotionality (e.g. anxiety, depression), and weak correlations with fear constructs that do not entail a direct link to a health threat. These results indicate the appropriateness of working with the Dutch ISI-R and its two subscales as a reliable and valid measure of fear of physical harm, Fear of Illness and Fear of Injury.