Faculty Presentations Faculty Presentations: Jennifer Mammen

Use of Mapping and Cognitive Interview Techniques in Evaluation of a Patient-Reported Outcome Measure for Freezing of Gait in Parkinson’s Disease: Status Update

Full list of poster authors

• Nami Shah
• Mirinda Tyo, PhD, RN
• Jocelyn Silva, RN
• Jeffrey M. Hausdorff, PhD
• Fay Horak, PhD PT
• Pieter Ginis, PhD
• Simon J G Lewis, MBBCh, BSc, MRCP, FRACP, MD
• Kaylena Ehgoetz Martens, PhD
• Alice Nieuwboer, PhD
• Jorik Nonnekes, MD, PhD
• Melissa Kostrzebski, MS, MBA
• Casey Dorney, MA
• Varun Gopal Reddy
• Jennifer Mammen, PhD, NP-C
• Jamie L. Adams, MD

Conference where poster was previously displayed 

IC FOG 2025

Poster abstract

Objective

To evaluate meaningful symptoms of freezing of gait (FOG) and perceived relevance of a new patient-reported outcome (PRO) that assesses FOG in Parkinson’s Disease (PD).

Background

FOG is a disabling PD symptom which contributes to falls, loss of independence, and progressive disability. A key research gap is that there are currently imprecise definitions and no well-validated, reliable measures that can support therapeutic development to treat FOG. Prior measure development efforts were challenged by the fluctuating nature of FOG and nuances of symptom severity and triggers. An international, multi-center study (FOG-COA) will develop a new PRO to address this gap. Our concurrent companion qualitative study will assess patient perceived relevance of the new PRO.

Methods

For the qualitative study, participants recruited from the parent FOG-COA study (N= 40-50) will complete the PRO surveys and subsequently engage in 1:1 interviews with trained clinician interviewers. Interviews will involve symptom mapping of all individually experienced motor and non-motor symptoms to delineate impacts and identify the symptom’s relationship to FOG (if any). Cognitive interview techniques will be used to evaluate relevance of the PRO survey. Participants will confirm relevance by directly mapping survey items onto personal symptom maps. Maps will be analyzed for symptom frequencies, impacts, relevance of
PRO items, and key themes. All interview procedures were co-developed with a patient advisory council and pretested with 8 patient volunteers to refine procedures prior to data collection.

Results

Sixteen participant interviews have been completed thus far, and detailed analysis is ongoing. Preliminary review indicates that all participants have found the symptom mapping process to be insightful, with many commenting on how the process has allowed them to realize the interplay between FOG, changes in mood, reduced independence, and increased social isolation. The fear of falling due to FOG was also thought to be very bothersome, even in the absence of actual falls or injuries. The majority of PRO items were rated as personally relevant and broadly useful assessments of FOG. Many participants indicated that even PRO items that were not yet personally relevant were still useful when assessing FOG in a broader population of people with PD. We hypothesize that final analysis will further emphasize how well symptom mapping and cognitive interview techniques can capture nuances of FOG and its interplay with other PD symptoms. These techniques can guide further assessment and refinement of the proposed PRO.

Conclusion

Our study describes a hybrid mixed-methods interview technique that can be used to capture the complexity of FOG experienced by PD patients. This technique can also be used to evaluate and refine PROs for future therapeutic clinical trials.