Development and initial psychometric evaluation of the Perceptions of Parental Illness Questionnaire for Cancer.

Objective: To evaluate the psychometric properties of the Perceptions of Parental Illness Questionnaire for Cancer (PPIQ-C) among adolescents and young adults (AYAs).

Methods: A sample of 372 AYAs (aged 12-24 years) who had a parent diagnosed with cancer completed the PPIQ-C and the Kessler Psychological Distress Scale (K10). Exploratory factor analyses were conducted to examine the dimensional structure of the PPIQ-C. Scale reliability was evaluated using Cronbach's alpha (α) and McDonald's omega (ω). Pearson correlation analyses were conducted to assess construct validity by examining correlations between PPIQ-C subscale scores and K10 total scores.

Results: The PPIQ-C is organised into three sections, each with a separate factor structure for items representing identity, core (emotional representations, coherence, timeline, consequences, and controllability), and cause dimensions of the Common-Sense Model of Self-Regulation. Exploratory factor analyses determined the structure of each section: identity items comprised two subscales (12 items), core items comprised 10 subscales (38 items), and cause items comprised three subscales (11 items). Scale reliability was acceptable for all subscales, except the cause subscale chance or luck attributions (α = 0.665). Correlations between PPIQ-C subscale scores and K10 total scores provided support for construct validity.

Conclusions: Preliminary evidence suggests that the PPIQ-C is a reliable, valid, and useful tool for assessing illness perceptions among AYAs with a parent with cancer. The PPIQ-C may be a useful addition to both clinical practice and future research, however further evaluation work is needed to confirm its structure and robustness prior to use.