2. Tan DM, McGinley JL, Danoudis ME, Iansek R, Morris ME. Freezing of gait and activity limitations in people with Parkinson’s disease. Arch Phys Med Rehabil 2011;92:1159–65.
3. Forsaa EB, Larsen JP, Wentzel-Larsen T, Alves G. A 12-year population-based study of freezing of gait in Parkinson’s disease. Parkinsonism Relat Disord 2015;21:254–8.
5. Giladi N, McMahon D, Przedborski S, Flaster E, Guillory S, Kostic V, et al. Motor blocks in Parkinson’s disease. Neurology 1992;42:333–9.
6. Bloem BR, Hausdorff JM, Visser JE, Giladi N. Falls and freezing of gait in Parkinson’s disease: a review of two interconnected, episodic phenomena. Mov Disord 2004;19:871–84.
8. Georgy E. Freezing of gait in Parkinson’s disease: impact on falls risk, walking aids utilization, and assistance-seeking behavior. Eur J Adapt Phys Act 2010;3:49–59.
9. Giladi N, McDermott MP, Fahn S, Przedborski S, Jankovic J, Stern M, et al. Freezing of gait in PD: prospective assessment in the DATATOP cohort. Neurology 2001;56:1712–21.
10. Moore O, Peretz C, Giladi N. Freezing of gait affects quality of life of peoples with Parkinson’s disease beyond its relationships with mobility and gait. Mov Disord 2007;22:2192–5.
11. Santos García D, de Deus Fonticoba T, Suárez Castro E, Borrué C, Mata M, Solano Vila B, et al. Non-motor symptoms burden, mood, and gait problems are the most significant factors contributing to a poor quality of life in non-demented Parkinson’s disease patients: results from the COPPADIS Study Cohort. Parkinsonism Relat Disord 2019;66:151–7.
12. Giladi N, Shabtai H, Simon ES, Biran S, Tal J, Korczyn AD. Construction of freezing of gait questionnaire for patients with Parkinsonism. Parkinsonism Relat Disord 2000;6:165–70.
15. Nilsson MH, Hagell P. Freezing of Gait Questionnaire: validity and reliability of the Swedish version. Acta Neurol Scand 2009;120:331–4.
16. Baggio JA, Curtarelli MB, Rodrigues GR, Tumas V. Validity of the Brazilian version of the freezing of gait questionnaire. Arq Neuropsiquiatr 2012;70:599–603.
19. Candan SA, Çatıker A, Özcan TŞ. Psychometric properties of the Turkish version of the freezing of gait questionnaire for patients with Parkinson’s disease. Neurol Sci Neurophysiol 2019;36:44–50.
21. Yardley L, Beyer N, Hauer K, Kempen G, Piot-Ziegler C, Todd C. Development and initial validation of the Falls Efficacy Scale-International (FES-I). Age Ageing 2005;34:614–9.
24. Thiamwong L. Psychometric testing of the Falls Efficacy Scale-International (FES-I) in Thai older adults. Songkla Med J 2011;29:277–87.
28. Qutubuddin AA, Pegg PO, Cifu DX, Brown R, McNamee S, Carne W. Validating the Berg Balance Scale for patients with Parkinson’s disease: a key to rehabilitation evaluation. Arch Phys Med Rehabil 2005;86:789–92.
29. Beaton DE, Bombardier C, Guillemin F, Ferraz MB. Guidelines for the process of cross-cultural adaptation of self-report measures. Spine (Phila Pa 1976) 2000;25:3186–91.
30. Schober P, Boer C, Schwarte LA. Correlation coefficients: appropriate use and interpretation. Anesth Analg 2018;126:1763–8.
31. Taber KS. The use of Cronbach’s alpha when developing and reporting research instruments in science education. Res Sci Educ 2018;48:1273–96.
32. Koo TK, Li MY. A guideline of selecting and reporting intraclass correlation coefficients for reliability research. J Chiropr Med 2016;15:155-63. Erratum in: J Chiropr Med 2017;16:346.
33. Elbers RG, van Wegen EE, Verhoef J, Kwakkel G. Is gait speed a valid measure to predict community ambulation in patients with Parkinson’s disease? J Rehabil Med 2013;45:370–5.
34. Adkin AL, Frank JS, Jog MS. Fear of falling and postural control in Parkinson’s disease. Mov Disord 2003;18:496–502.