Development and Psychometric Evaluation of the Children's Illness-Related Concerns Scale.

Background: Despite the effect of maternal breast cancer on many children, there is no valid or reliable quantitative measure of the concern that children attribute to their mothers' disease, which constrains both science and clinical practice.

Objectives: This study aimed to develop and psychometrically evaluate the initial measures of child-reported, illness-related concerns associated with maternal cancer.

Methods: The study was conducted in three phases: scoping review, item extraction from a battery of items obtained from school-aged children about general issues related to their mothers' breast cancer, and testing of the three proposed structural models of these extracted items using confirmatory factor analysis. The scoping review yielded five categories of illness-related concerns: altered family routines, uncertainty, concerns about illness contagion, maternal death, and maternal well-being. To reflect these five categories, 18 items were extracted from a 93-item questionnaire completed by 202 school-aged children regarding their mothers' breast cancer. Next, three structural models were hypothesized to assess the construct validity of illness-related concerns: five-, three-, and one-factor models. Confirmatory factor analysis was used to test and compare the models.

Results: The five-factor model best fit the data, and each factor showed adequate internal consistency reliability. These findings align with the a priori five-factor model informed by the scoping review.

Conclusion: The results provide initial evidence of the construct validity of the 18-item Children's Illness-Related Concerns Scale, which can be used to assess children's concerns and inform future intervention studies.