Structural, age, and sex differences for a short form of the inventory of parent and peer attachment: the IPPA-45

The Inventory of Parent and Peer Attachment (IPPA) is the most widely used self-report measure of adolescent attachment relationships. This study reports the development of the IPPA-45, a short-form of the IPPA that assesses the quality of mother, father, and peer attachment relationships. A hierarchical measurement model is proposed with three lower-order factors and a higher-order factor. Confirmatory factor analyses were conducted using a sample of 1,025 English-speaking adolescents (387 males) aged 13 to 18 years. Results support the hierarchical factor structure, and tests of model invariance demonstrated that the measurement models were similar regardless of age or sex. Differences in mean scores were found with regard to attachment target, gender and age. Overall, the IPPA-45 is supported as a psychometrically sound measure of relationship attachment across the age-range of adolescence.