On the question of an identity status category order: Rasch model step and scale statistics used to identify category order

The question of whether or not a developmental continuum underlies James Marcia's identity statuses has been a topic of debate among identity researchers for nearly 20 years. This study addressed the prefatory question of whether the identity statuses can be empirically ordered in a theoretically optimal way. This question was addressed via use of Rasch model threshold and scale statistics, which effectively differentiated empirically optimal from suboptimal category orders. All permutations of Marcia's 4 identity statuses were generated in relation to stages from Loevinger's model of ego development and Kegan's model of self—other differentiation. The optimal identity status order found was diffusion, foreclosure, moratorium, to achievement in 2 sets of analyses, and diffusion combined with foreclosure to moratorium, to achievement in 2 additional sets of analyses. The order diffusion, foreclosure, achievement, to moratorium performed nearly as well in one set of analyses. Results, in general, support the theoretically optimal category order. Rasch model threshold and scale statistics can be effectively applied to place categories into an empirically optimal order or to assess the match between theoretical and empirical category orders.