AQS (Attachment Q-set; Version 3)

Measure DescriptionSource of measure Waters, E. (1987). Appendix A: The Attachment Q-Set Version 3.0. Monographs of the Society for Research in Child Development, 60, 234-246. doi: 10.2307/1166181; Waters, E. (1987). Attachment Q-set (Version 3). Retrieved (11 Sept 2017) from
Mode of administration Home observation
Age range for use1 to 5
Domains AssessedAttachment: security scale and dependency scale.
Related MeasuresStrange Situation Procedure
BurdenTraining needed to administerTraining occurs over the course of a few months, during which trainees watch videotapes and practice coding the AQS.
Minutes to complete2 observations of 1.5-2 hours each
# of items90
Adaptation for AIAN useAdaptedNo
Developer allows adaptation?Yes, contact developer.
Used with AIAN populations?None documented.
AIAN: Cronbach's alpha rangeNot yet available.
AIAN: Evidence of validityNot yet available.
Other populations: Cronbach's alpha rangeInterrater reliability across 22 studies ranged from .94 to 1.00, and the AQS demonstrates modest stability over time (r = .28; van IJzendoorn, Veriejken, Bakermans-Kranenburg, & Risken-Walraven, 2004).
Other populations: Evidence of validityA meta-analysis of studies using the AQS supports the validity of the observer AQS, demonstrating its convergent validity with the SSP (r = .31), predictive validity with sensitivity (r = .39) and socio-emotional competence (r = .22) and divergent validity with measures of temperament (van IJzendoorn, Veriejken, Bakermans-Kranenburg, & Risken-Walraven, 2004). The AQS also shows convergent validity with story-stem attachment tasks (Waters, Rodrigues, & Ridgeway, 1998).
SourceDeveloperEverett Waters, PhD
SummaryComments about sensitivity to changeAQS scores were improved in the intervention group following a short-term attachment-based intervention in a group of maltreating families (Moss et al., 2011). Attachment security, assessed by AQS, also improved following both home visiting and attachment-based programs (Niccols, 2008).
General remarksThe AQS can also be adapted for use in child care settings to assess a child's attachment style to his/her child care provider(s).

Table Updated October 10, 2017