Samenvatting

Background
The Pictorial Fear of Activity Scale-Cervical (PFActS-C) is a reliable and valid instrument to assess fear of movement in people with whiplash associated disorders. It is not available in Dutch and has not been evaluated in other neck pain populations. This study aimed to systematically translate the PFActS-C into Dutch and evaluate the psychometric properties of this Dutch Language Version (DLV) in people with non-specific neck pain.

Methods
The PFActS-C was translated according to international guidelines. Internal consistency, test-retest reliability, floor and ceiling effects, face validity and construct validity (convergent and discriminant validity by hypotheses testing and structural validity by confirmatory and exploratory factor-analyses) of the PFActS-C-DLV were tested in 125 people with non-specific neck pain.

Results
The PFActS-C-DLV showed good to excellent internal consistency (Cronbach’s alpha: 0.98) and stability over time (ICC: 0.90 [95%CI: 0.82–0.93). Four out of five a priori formulated hypotheses regarding related (convergent validity) and unrelated (discriminant validity) constructs were confirmed. However, the confirmatory factor analysis could not confirm the expected 1-factor solution. Furthermore, the exploratory factor analyses revealed that also a higher factor solution would not lead to a good fit of the model.

Conclusions
The PFActS-C-DLV is a reliable region-specific instrument for people with non-specific neck pain. The construct validity was supported, based on hypotheses testing. However, factor analyses could not confirm a 1-factor solution, so the underlying construct of the PFActS-C-DLV remains unclear. Given the PFActS-C’s photographic format, we believe these findings also have relevance for the original English version.