Objective: Validate and demonstrate reliability of the NoMoFA.

Background: In patients with PD, sleep, mood, cognitive, autonomic and other non-motor symptoms (NMS) may fluctuate (NMF) in a manner similar to motor symptoms. While NMF may be amenable to medical and surgical interventions, the absence of a valid tool to capture them, has prevented efforts to confirm and quantify the impact of any intervention.
We developed a 29-item Non-Motor Fluctuation questionnaire using qualitative research methodology. The questionnaire is completed by the patient and/or caregiver and includes NMS that are known to fluctuate. Initial validation demonstrated overall excellent internal consistency and reliability of the questionnaire with additional  cognitive pretesting performed on 4 items. This study sought to perform item reduction and validate the final form of the questionnaire.

Method: PD subjects were recruited from 5 movement disorders centers across the US and Canada. We assessed the clinimetric properties of NoMoFA including concurrent validity, floor and ceiling effects, and test-retest reliability. Classical test theory and item response theory methods informed item reduction and additional Delphi process yielded a final validated questionnaire.

Results: Two hundred PD subjects and their care-partners participated in the study. Mean age ± standard deviation was 66.4±9.6 years with a mean disease duration of 9±5.5 years. Median Hoehn and Yahr (H&Y) OFF was 3 (range 1-5) with 43.4% mild (H&Y 1-2), 35.7% moderate (H&Y 2.5, 3) and 21% severe (H&Y 4, 5). Mean UPDRS III ON score was 27.4 ± 14.85. The acceptability of the scale was adequate. There were floor effects in 8/29 items. Cronbach’s alpha was 0.894. Eight items in “item-to-total” correlation analysis did not significantly contribute to the overall domain of the scale (item-total ≤ 0.4). However, removing these items did not improve Cronbach’s alpha. Test-retest reliability was excellent (ICC = 0.73 (95th CI 0.64 – 0.80)). Convergent validity was adequate with Spearman’s rho correlation coefficient values comparing NoMoFA score to other measures of Parkinsonian severity all significant and in the expected direction. A final Delphi panel determined the elimination of one item to avoid redundancy.

Conclusion: The final 28-item self-administered NoMoFA is a valid and reliable instrument, capturing NMF in PD.

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MDS Abstracts - https://www.mdsabstracts.org/abstract/non-motor-fluctuations-in-parkinsons-disease-pd-development-and-validation-of-the-non-motor-fluctuation-assessment-instrument-nomofa/