Communicative participation outcomes in individuals with Parkinson's disease receiving standard care speech-language therapy services in community settings

Background The Communicative Participation Item Bank (CPIB) is a patient-reported outcome measure (PROM) designed to measure the extent of interference, or difficulty, experienced by adults with communication disorders participating in their day-to-day communication activities. To date, there is limited evidence regarding sensitivity of the CPIB for capturing change with intervention in people with Parkinson's disease (PwPD).Aims The purpose of this study was to examine the following measurement properties of the CPIB in PwPD who received community-based, standard care, speech-language therapy focusing on motor speech concerns: Change over time between treatment and observation groups, comparison to patient-defined ideal and satisfactory targets, comparison of static short form to computerised adaptive testing (CAT), comparison of self to proxy-rated scores, and comparison to other common PROMs.Methods and Procedures Forty-six PwPD (20 treatment/26 observation) completed data collection upon enrolment (pre-treatment) and 6 months later. In addition to the CPIB, PROMs included the Voice Handicap Index 10-item short form (VHI-10), PROMIS Global Health-Related Quality of Life, Levels of Speech Usage, self-rated speech severity, and Patient Health Questionnaire-9 (PHQ-9). Participants also engaged in qualitative interviews. Forty-four family members completed proxy CPIB ratings.Outcomes and Results There were no significant differences between treatment and observation groups on the CPIB pre-treatment, but there were significant differences post-treatment. The differences appeared to be largely due to significant gains in the treatment group. No participants reached their ideal CPIB target, and few reached their satisfactory target. Static CPIB short form and CAT scores were not significantly different, with an average of five CAT items administered per participant. Overall group similarities between patient and proxy scores may have obscured wide variability across individual patient-proxy pairs. Associations between CPIB and VHI-10, health-related quality of life, self-reported speech severity, and depression ranged from weak to moderate.Conclusions and Implications The CPIB appears to be sensitive to capturing change with intervention, and similar results are obtained with the static short form and CAT formats. One clinical caution is that even with gains observed in the treatment group, no participants obtained their ideal communicative participation goals, and few obtained a satisfactory level of communicative participation. Thus, while current interventions are beneficial, they may not meet the full range of clients' communication needs. While responding to the CPIB through a proxy rater may be feasible, caution is warranted due to concerns about maintaining the autonomy of PwPD.