TY  - JOUR
PY  - 2020//
TI  - The new freezing of gait questionnaire: unsuitable as an outcome in clinical trials?
JO  - Movement disorders clinical practice
A1  - Hulzinga, Femke
A1  - Nieuwboer, Alice
A1  - Dijkstra, Bauke W.
A1  - Mancini, Martina
A1  - Strouwen, Carolien
A1  - Bloem, Bastiaan R.
A1  - Ginis, Pieter
SP  - 199
EP  - 205
VL  - 7
IS  - 2
N2  - BACKGROUND: Freezing of gait (FOG) is a common gait deficit in Parkinson's disease. The New Freezing of Gait Questionnaire (NFOG-Q) is a widely used and valid tool to quantify freezing of gait severity. However, its test-retest reliability and minimal detectable change remain unknown. <br><br>OBJECTIVE: To determine the test-retest reliability and responsiveness of the NFOG-Q. <br><br>METHODS: Two groups of freezers, involved in 2 previous rehabilitation trials, completed the NFOG-Q at 2 time points (T1 and T2), separated by a 6-week control period without active intervention. Sample 1 (N = 57) was measured in ON and sample 2 (N = 14) in OFF. We calculated various reliability statistics for the NFOG-Q scores between T1 and T2 as well as correlation coefficients with clinical descriptors to explain the variability between time points. <br><br>RESULTS: In sample 1 the NFOG-Q showed modest reliability (intraclass correlation coefficient = 0.68 [0.52-0.80]) without differences between T1 and T2. However, a minimal detectable change of 9.95 (7.90-12.27) points emerged for the total score (range 28 points, relative minimal detectable change of 35.5%). Sample 2 showed largely similar results. We found no associations between cognitive-related or disease severity-related outcomes and variability in NFOG-Q scores. <br><br>CONCLUSIONS: We conclude that the NFOG-Q is insufficiently reliable or responsive to detect small effect sizes, as changes need to go beyond 35% to surpass measurement error. Therefore, we warrant caution in using the NFOG-Q as a primary outcome in clinical trials. These results emphasize the need for robust and objective freezing of gait outcome measures.<br><br>© 2020 International Parkinson and Movement Disorder Society.<p />  <p>Language: en</p>
LA  - en
SN  - 2330-1619
UR  - http://dx.doi.org/10.1002/mdc3.12893
ID  - ref1
ER  -