Although it is a widely used questionnaire, limitations regarding the scoring procedure
and the structural validity of the eight-item Reflective Functioning Questionnaire
(RFQ-8) were raised. The present study aimed to examine further the latent dimensionality
of the RFQ-8 and to examine linear and non-linear associations between mentalization
difficulties and maladaptive psychological characteristics. Data from two separate
representative samples of young adults ( N = 3890; females: 51.68%; mean age: 27.06
years [ SD = 4.76]) and adults ( N = 1385; females: 53.20%; mean age: 41.77 years
[ SD = 13.08]) were used. In addition to the RFQ-8, standardized questionnaires measured
the levels of impulsivity, sensation seeking, rumination, worry and well-being. Confirmatory
factor analysis (CFA) was used to test the model fit of competing measurement models.
CFA revealed that a revised, seven-item version of the RFQ (RFQ-R-7) with a unidimensional
structure showed the most optimal levels of model fit in both samples. Impulsivity,
sensation seeking, rumination and worry consistently presented significant, positive,
linear associations with general mentalization difficulties in both samples. Significant
quadratic associations were also identified, but these relationships closely followed
the linear associations between the variables and increased only marginally the explained
variance. The supported unidimensional measurement model and the associations between
the general mentalization difficulties factor and maladaptive psychological characteristics
indicated that the RFQ-R-7 captures a dimension of hypomentalization ranging between
low and high levels of uncertainty. Increasing levels of hypomentalization can indicate
a risk for less adaptive psychological functioning. Further revisions of the RFQ-8
might be warranted in the future to ensure adequate measurement for hypermentalization.
