Measuring the impact of trigeminal neuralgia pain: the Penn Facial Pain Scale-Revised.

BACKGROUND AND OBJECTIVE

The Penn Facial Pain Scale (Penn-FPS) was originally developed as a supplemental module to the Brief Pain Inventory Pain Interference Index (BPI-PII) in order to fully assess the impact of trigeminal neuralgia (TN) pain on patients' health-related quality of life (HRQoL). The current objective is to create and establish the content validity of a new stand-alone version of the measure, the Penn-FPS-Revised (Penn-FPS-R).

METHODS

Twenty participants (15 USA and 5 UK) with confirmed TN engaged in concept elicitation and cognitive debriefing interviews. These semi-structured interviews allowed participants to spontaneously describe the ways in which TN impacts on HRQoL and report on the extent to which the Penn-FPS and BPI-PII measure concepts are most relevant to them. Participants were also asked to report on the suitability of the instructions, recall period, and response options.

RESULTS

Concept elicitation revealed nine themes involving TN restrictions on daily activities and HRQoL, including: "talking," "self-care," "eating," "eating hard foods/chewing foods," "daily activities," "activities with temperature change," "touching," "mood," and "relationships." Cognitive debriefing confirmed that all of the Penn-FPS concepts and some of the BPI-PII concepts ("mood," "general activities," and "relations with others") were relevant, although some items required edits to better capture individuals' experiences. The impact of temperature and/or weather on activities was also identified as an important concept that is not captured by the Penn-FPS or BPI-PII. Participants confirmed the acceptability of recall period, instructions, and response options. Results from the interviews were applied to create the Penn-FPS-R, a new brief outcome measure that assesses the impacts of TN most important to patients.

CONCLUSION

The Penn-FPS-R is a new 12-item HRQoL outcome measure with content validity that can be used to assess and monitor the impact of TN treatment interventions in both clinical practice and research.