Reassessing the validity of the attachment Q-sort: An updated meta-analysis

A 2004 meta-analysis reported good validity for the observer attachment Q-sort (AQS), but poor validity for the parental self-report version. Despite this, the self-report AQS is still widely used, with researchers arguing that providing additional training can improve its validity. The aim of this study was to update the 2004 meta-analysis. Two hundred forty-five studies from 1987 to 2016 were included (n = 32,426). Separate meta-analyses were conducted to examine validity and reliability. The observer AQS showed moderate convergent validity with the Strange Situation Procedure (r = .25; r = .39 for long observation periods) and good predictive validity in terms of associations with sensitivity (r = .32). It showed a relatively weak association with infant temperament (r = .21), suggesting some discriminant validity. The self-report version showed comparable convergent validity with Strange Situation Procedure (r = .18), but significantly weaker correlations with sensitivity (r = .25) and stronger correlations with temperament (r = .33). There was no evidence that providing additional training improved the validity of the self-report version. This study corroborates the previous finding that the observer AQS is a valid measure of infant attachment, especially after long periods of observation. The self-report version showed significantly weaker discriminant and predictive validity.