Perseverative Negative Thinking (PNT) is a transdiagnostic cognitive process  characterized by repetitiveness, intrusiveness and difficulties to disengage (Ehring, 2011). The Perseverative Thinking Questionnaire (PTQ-15; ) is a self-reported instrument, developed to evaluate these characteristics. The Portuguese version assess two meaningful dimensions – Repetitive thoughts (RT); and Cognitive interference and unproductiveness (CIU) .
To confirm the bi-dimensional structure of the PTQ-15 using Confirmatory Factor Analysis, in two distinct samples.
A sample composed of 256 students (Mean age = 20.58 ± 1.870; 78.1% girls) and a sample composed of 480 adults from the community (parents of the students; mean age = 50.84 ± 5.310; 53.1% women) filled the PTQ-15. We used software AMOS.
The second-order model of PTQ-15 with two dimensions presented good fit, in both students (CMIN = 2.449; RMSEA = 0.075; CFI = 0.958, TLI = 0.949, PGFI = 0.776; P < 0.001) and their parents (CMIN = 3.46; RMSEA = 0.072, CFI = 0.955, TLI = 0.942, PGFI = 0.632; P < 0.001). Internal consistency of the total scale, measured though Cronbach's alpha was α = 0.95/0.94; both factors presented good/excellent reliability: repetitive thoughts (a = 0.93/0.92); cognitive interference and unproductiveness (a = 0.88/0.92).
Taken together, both CFAs provided additional evidence that PTQ-15 is an adequate measure for perseverative thinking.
The authors have not supplied their declaration of competing interest.