The AQC has shown evidence of concurrent validity with the Inventory of Parent and Peer Attachment (IPPA), Spence Children’s Anxiety Scale (SCAS), and the Children’s Depression Inventory (CDI) in a non-clinical population of 155 adolescents ranging in age from 12 to 14 years from a regular secondary school.

Adolescents classified as securely attached, based on AQC responses, had higher levels of trust and lower levels of alienation, as assessed using the IPPA. They also had lower scores on Anxiety (SCAS) and Depression (CDI) than did insecurely attached adolescents. Ambivalently attached adolescents had higher levels of SCAS and CDI symptomatology than did Securely or Avoidantly attached adolescents (Muris et al., 2001).

Across different studies, children who define themselves as insecurely attached display higher levels of anxiety, worry, and depression than those who identify themselves as securely attached (Muris, Mayer, & Meesters, 2000; Muris, Meesters, Merckelbach, & Hülsenbeck, 2000).

Muris, Mayer, & Meesters (2000) found that insecurely attached children had higher scores on the Screen for Child Anxiety Related Disorders and Depression Questionnaire for Children. In a large sample of 724 adolescents aged 12-18 (M=14.45, SD=1.39), Muris, Meesters, & van den Berg (2003) reported that securely attached children reported lower scores on the Youth Self-Report scales (Internalizing, Externalizing, Anxious-depressed, Somatic complaints, Aggressive behavior, and Delinquent behavior).

Muris & Meesters (2000) found that for both adolescent and parent reports, there was a connection between attachment status and behavioral inhibition and anxiety symptoms, as assessed, using the Revised Children’s Anxiety and Depression Scale (RADS). AQC classifications accounted for unique variance in the prediction of anxiety disorders when RADS scores were predicted using Attachment classification and a measure of Behavioral Inhibition. Muris, Meesters, Merckelbach, & Hülsenbeck (2000) reported that insecure attachment was related to children’s worries, as assessed using the Penn State Worry Questionnaire for Children.

Attachment categories also appear to be related, as expected, to aspects of the parent-child relationship. Attachment categories are related to scores on the Egna Minnen Betraffende Uppfostran (EMBU-C), a measure that assesses perceptions of parental rearing behaviors. Securely attached adolescents perceived their parents as more emotionally warm and less rejecting and overprotective (Muris, Meesters, & van den Berg, 2003).

In a study of 159 predominantly Caucasian children aged 9 to 13, recruited from primary schools in the Netherlands, ambivalently attached children reported more reported more anxious rearing by mothers and fathers (EMBU-C) than did securely attached children), and avoidant children reported greater perceived rejection from both their mothers and fathers (Muris et al., 2000).

RESEARCH ON OTHER VERSIONS OF THE AQC

1. A variation of the adult AQ with very similar wording has also been used in a study examining the relation between attachment style and weight concern in an ethnically diverse sample of 355 4th- to 8th-grade girls, mean age = 11.9 (37.8% White, 25.7% Latina, 21.7% Asian, 5.9% African American, and 8.9% Other). In this study 68% of girls were classified as securely attached and 32% were classified as insecurely attached. Insecurely attached girls had significantly lower self-esteem scores and higher weight concerns than did securely attached girls (Sharpe et al., 1998). Given that the wording is so similar to the version reviewed in this report because both are based on the adult AQ, it is likely that the psychometric findings would be similar to the version reviewed.
2. An educator/caregiver version of the AQC has been used in a sample of 39 institutionalized and 40 non-institutionalized Dutch children with mental retardation (Muris & Maas, 2004). The institutionalized sample included 22 boys and 17 girls with a mean age of 10.7 years. Children were from low SES backgrounds, 24.3% had a history of sexual abuse, 43.2% had a history of physical abuse, and 81.1% had been seriously neglected during early childhood. The majority (73.0%) were from divorced families. The non-institutionalized sample included 27 boys and 13 girls with a mean age of 10.3 years, 35% came from divorced families, and 12.5% no longer had contact with their biological family. Non-institutionalized children were matched with institutionalized children based on educational level. There were, however, no available data on their trauma history. Institutionalized children were more likely to be categorized as insecurely attached, using both caregiver and teacher reports. For both institutionalized and non-institutionalized children, caregiver and teacher reports showed higher levels of total difficulties, using the Strengths and Difficulties Questionnaire (SDQ) for Children categorized as insecurely attached. Examination of SDQ subscales showed that the relationship was strongest for emotional problems and peer problems, lending further support for the validity of the AQC. In addition, for caregiver reports of non-institutionalized children and teacher reports of institutionalized children, insecurely attached children showed significantly less prosocial behavior. Sensitivity and Specificity were assessed compared to clinical cutoffs on the Strengths and Difficulties Questionnaire. For caregiver reports, Sensitivity=80%, Specificity=64.3%. For teacher report, Sensitivity=78.3%, Specificity=69%. When teacher and caregiver reports were combined, Sensitivity=81.3%, Specificity=73.8%.
3. Finzi et al. (1996) have conducted a number of studies using their 15-item version adapted from the Hazan & Shaver (1987) original AQ for adults. Their studies are summarized in this database under the review for the Attachment Style Classification Questionnaire.