Commitment in different relationships statuses: validation study of the personal commitment scale

This study presents the validation process of the Portuguese version of the short-form Dedication Scale (Rhoades, Stanley, & Markman, 2006; Stanley, 1986), with a sample of 924 participants in different relationship statutes. With 14 items, this short version is recommended by the authors for its simple use, when wanting to measure commitment in romantic relationships. Confirmatory factor analysis showed that the instrument did not have a totally acceptable fit with the data so an exploratory factor analysis was conducted. This revealed a one-dimensional structure of the scale, and led to the exclusion of two items, which relate to a distinct meta-commitment dimension. In sum, the Portuguese version (ECP - Personal Commitment Scale) has 12 items, with good internal consistency (α = .82), correlations item-total between .36 and .60, and good criteria validity (p < .001). Its use for research is therefore appropriate. In a second study, significant differences were found between the participants' four relationship statuses (dating non-cohabiting and cohabiting relationships, formal unions and marriage) (p < .001; η2 p = .03). Results showed that married participants were more committed than those in a formal union, even when controlling for several relational and socio-demographic variables. No differences were found between cohabiting and non-cohabiting dating participants. Men reported higher levels of commitment than women (p < .001; η2 p = .02). Implications and suggestions for future research are discussed.