The development and validation of the partial denture experience questionnaire (P-DEQ): reliability and validity

Introduction This paper describes the development and preliminary validation of the Partial Denture Experience Questionnaire (P-DEQ), a new, condition-specific instrument designed to measure the multifaceted impacts of living with removable dentures. Methods The P-DEQ was developed using a multi-phase, mixed-methods design. Item generation was informed by qualitative interviews (n = 20) with denture wearers in the UK and guided by the World Health Organisation's International Classification of Functioning, Disability and Health (ICF) framework. A 34-item scale, with five core sub-scales (Body Function, Emotional Function, Daily Abilities, Social Impacts and Participation Restrictions) and a separate ‘My Denture’ sub-scale, was tested in a cross-sectional study with online panels from the UK (n-224) and US (n-224). Reliability, item-total correlations, item impacts and sub-scale correlations were assessed. Results The P-DEQ sub-scales demonstrated good to excellent reliability (Cronbach's α = 0.71–0.88) across both samples. Sub-scale-to-total score correlations were high and significant, with the Emotional Function (r = 0.92) and Social Participation (r = 0.92) sub-scales showing particularly strong relationships in the UK sample. Most item-total correlations exceeded the 0.4 threshold, supporting the instrument's underlying coherence. Item impact scores varied widely; items concerning psychosocial worries (e.g., the denture breaking) and functional limitations (e.g., avoiding certain foods) registered the highest impact. In contrast, items reflecting potential benefits of the denture, such as improved appearance, had lower impact scores. Furthermore, the ‘My Denture’ sub-scale, measuring personal appraisal of the prosthesis, was significantly correlated with the total P-DEQ score (r = −0.50 UK; r = −0.55 US), indicating that a more favourable personal evaluation of a denture was associated with fewer negative impacts. Conclusions The P-DEQ demonstrates promising reliability and content validity for assessing the complex experience of living with a removable denture. The instrument is sensitive to the nuanced, often ambivalent, emotional states of wearers. Whilst this initial validation is based on cross-sectional data, longitudinal testing is required for item reduction and to fully establish the P-DEQ as a robust measure that can detect change over time.