Table 2 Overview of the studies included in this meta-analysis

Margolesky et al [36]

United States

102

19

freezing of gait was self-reported

68.0 ± 10.0

5.3 ± 4.8

1-4

Mckay et al [46]

United States

65

18

FOG-Q item 3 > 1 or UPDRS item 14 > 1

68 ± 10

7.3 ± 5.6

1-3

Mancini et al [40]

Israel

94

16

new FOG-Q part I = freezer

65.4 ± 9.7 for non-freezers; 64.2 ± 8.8 for freezers

4.9 ± 2.8 for non-freezers; 7.6 ± 4.4 for freezers

2.4 ± 0.5 for non-freezers; 3.2 ± 0.8 for

Djaldetti et al [37]

Israel

41

14

UPDRS item 14 > 1

63.5 ± 9.9

9.5 ± 3.2

1-3

Ehgoetz Martens et al [38]

Australia

221

15

FOG-Q item 3 ≥ 1

65.4 ± 9.8 for non-freezers; 70.8 ± 9.4 for transitional freezers; 70.2 ± 10.9 for continuing freezers

3.2 ± 4.3 for non-freezers; 6.0 ± 4.1 for transitional freezers; 9.7 ± 7.5 for continuing freezers

ND

Kader et al [44]

Sweden

243

16

FOG-Q item 3 ≥ 1

70 ± 9.2

8 (1–43)^a

Sutter et al [45]

United States

111

16

new FOG-Q item 1 > 0

66.5 ± 1.7

1-4

Forsyth et al [43]

Australia

82

16

new FOG-Q

66.5 ± 7.6

7.5 ± 5.7

2.0 ± 0.7

Ricciardi et al [41]

Italy

43

15

new FOG-Q item 1 > 0

68.0 ± 11.6

5.3 ± 5.4 for non-freezers; 9.5 ± 5.8 for freezers

ND

Vervoort et al [42]

Belgium

76

16

new FOG-Q or FOG occurrence in the lab

60.6 ± 10.0

6.8 ± 4.6

2.1 ± 0.5

Shin et al [35]

United states

141

14

freezing of gait was self-reported

69.7 ± 8.21

6.34 ± 4.84

ND

Allen et al [21]

Australia

231

14

freezing of gait was self-reported

70.6 ± 8.8

7.9 ± 5.9

ND

Amboni et al [11]

Italy

593

19

FOG-Q item 3 ≥ 1

66.1 ± 9.7 for non-freezers; 67.5 ± 8.7 for freezers

6.1 ± 3.8 for non-freezers; 9.8 ± 4.8 for freezers

1-5

Forsaa et al [22]

Norway

232

17

UPDRS item 14 ≥ 1

64.9 (28.2-86.0) ^b

8.6 ± 5.7

1-5

Gazibara et al [23]

Serbia

300

17

new FOG-Q item 1 > 0

61.4 (22–83)^b

0.5-30

1-4

Lieberman et al [24]

United States

212

14

UPDRS item 14 ≥ 2

ND

All patients < 5

1-5

Lindholm et al [25]

Sweden

141

15

FOG-Q item 3 ≥ 1

68 ± 9.7

4 ± 3.9

1-5

Walton et al [26]

Australia

203

15

FOG-Q item 3 ≥ 1

66.77 ± 8.9

5.1 ± 5.1

1-3

Bohnen et al [8]

United States

143

14

MDS-UPDRS item 3.11 ≥ 1

65.5 ± 7.4

6.0 ± 4.3

2.4 ± 0.5

Ou et al [27]

China

474

16

FOG-Q item 3 ≥ 1

62.09 ± 10.55

4.77 ± 4.04

1-5

Perez-Lloret et al [28]

French

672

19

UPDRS item 14 ≥ 1

50.7% patients ≥68

50.7% patients > 5

1-5

Auyeung et al [10]

China

171

17

sudden and transient blocks of movement while walking

62.2 ± 10.6

All patients > 10

1.5-5

Contreras et al [29]

Spain

160

16

FOG-Q item 3 ≥ 1

72.0 ± 9.5

8.1 ± 6.4

2.6 ± 1.0

Garcia-Ruiz et al [30]

Spain

45

15

sudden and transient blocks of movement while walking

58.5 ± 10.2

Josiah et al [31]

United States

916

14

UPDRS item 14 ≥ 1

67.1 ± 11.0

6.6 ± 6.0

ND

Coelho et al [32]

Spain and Portugal

50

15

ND

74.1 ± 7.0

17.9 ± 6.3

4-5

Moore et al [9]

Israel

118

16

FOG-Q item 3 ≥ 1

65.8 ± 10.2

8.5 ± 5.8

2.7 ± 0.8

Giladi et al [33, 34]

United States

800

15

UPDRS item 14 ≥ 1

61.1 ± 9.5

2.1 ± 1.3

1-2

Giladi et al [33, 34]

Israel

172

16

feet get glued to the ground was self-reported

58.3 ± 13.2

11.8 ± 5.6

1-5