Non- Motor Fluctuations in Parkinson’s Disease: Validation of the Non- Motor Fluctuation Assessment Questionnaire

BackgroundIn patients with Parkinson’s disease (PD), sleep, mood, cognitive, autonomic, and other non- motor symptoms may fluctuate in a manner similar to motor symptoms.ObjectivesTo validate a final version of a patient- rated questionnaire that captures the presence and severity of non- motor fluctuations in levodopa- treated PD patients (NoMoFA).MethodsWe recruited PD subjects from five movement disorders centers across the US and Canada. We assessed the internal consistency, floor and ceiling effects, test- retest reliability, and concurrent validity of NoMoFA. Classical test theory and item response theory methods informed item reduction and Delphi process yielded a final questionnaire.ResultsTwo hundred subjects and their care- partners participated in the study (age: 66.4- ±- 9.6- years; disease duration: 9- ±- 5.5- years; median Hoehn and Yahr [H&Y] OFF: 3 [range 1- 5]; mean Unified Parkinson’s Disease Rating Scale (UPDRS) III ON score: 27.4- ±- 14.9). Acceptability of the scale was adequate. There were floor effects in 8/28 items. Cronbach’s alpha was 0.894. While eight items had - item- to- total- correlations below the cutoff of 0.4, removing these items did not improve Cronbach’s alpha. Test- retest reliability was acceptable (intraclass correlation coefficient [ICC] 0.73; 95% confidence interval, 0.64- 0.80). Concurrent validity was adequate with all Spearman’s rho values comparing NoMoFA score to other measures of parkinsonian severity showing significance and in the expected direction. A final Delphi panel eliminated one item to avoid redundancy.ConclusionsThe final 27- item self- administered NoMoFA is a valid and reliable questionnaire, capturing both static and fluctuating non- motor symptoms in PD. © 2021 International Parkinson and Movement Disorder SocietyPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/168292/1/mds28507-sup-0001-Supinfo01.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168292/2/mds28507_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168292/3/mds28507-sup-0002-Supinfo02.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168292/4/mds28507.pd