Experienced emotional burden in caregivers: psychometric properties of the Involvement Evaluation Questionnaire in caregivers of brain injured patients

Objective: To examine the psychometric properties (internal consistency, discriminant validity, and responsiveness) of the Involvement Evaluation Questionnaire for Brain Injury measuring emotional burden in caregivers of patients with chronic acquired brain injury.Design: Inception cohort study.Subjects: Caregivers of chronic acquired brain injury patients.Main measures: Besides the Involvement Evaluation Questionnaire for Brain Injury, the Family Assessment Device and the General Health Questionnaire were used.Methods: Ninety-eight caregivers filled out all questionnaires, of which 41 caregivers did this twice, before and after the persons they cared for had started a residential community reintegration programme. Cronbach's alpha and Intra class Correlation Coefficient were calculated for internal consistency. Pearson correlation coefficients were used for discriminant validity and Intra class Correlation Coefficient and Cohen's d were calculated to determine responsiveness.Results: The internal consistency of the Involvement Evaluation Questionnaire for Brain Injury was good (alpha = 0.73-0.84; Intra class Correlation Coefficient = 0.69-0.76). As expected, low correlations were found between the Involvement Evaluation Questionnaire for Brain Injury and either the General Health Questionnaire (r = 0.11-0.40) or the Family Assessment Device subscales (r = -0.29-0.19). Regarding responsiveness of the Involvement Evaluation Questionnaire for Brain Injury, a moderate effect size was found (Cohen's d = 0.36) while the Intra class Correlation Coefficient was good (0.80).Conclusions: The Involvement Evaluation Questionnaire for Brain Injury measures the experienced emotional burden in caregivers of patients with chronic acquired brain injury and seems to be a promising new instrument with good internal consistency, discriminant validity and responsiveness.