Table 1 Summary of results of all studies included in the meta-analyses

Abramides 2015 [18], Sao Paolo, Brazil

Prospective study

120

24

42 (12–65)

Yes

P = 0.414

Basta 2008 [12] Berlin, Germany

Prospective study

42

18

(10–75)

Yes

ND

(NS)

Yes

ND

(NS)

Yes

P < 0.05

Yes

ND

(NS)

Bateucas 2015 [8] Salamanca, Spain

Prospective descriptive

2

30

54 ± 10

Yes

Yes

Bonucci 2008 [15] Sao Paolo, Brazil

NI*

NI*

38

30.65 ± 32

4–62

Yes

ND

Brey 1995 [14] Mayo clinic,Rochester, Minnesota

NI*

45 to 1770

52

3-87

Yes

P = 0.01

Yes

ND

Buchman 2004 [3] University of North Carolina, USA

Prospectivestudy

30

67

2-87

Yes

ND

Yes

ND

Coordes 2012 [13] Berlin, Germany

Prospective study

NI*

17

60 (20–73)

Yes

ND

Ernst 2006 [30] Berlin, Germany

Prospective study

365

18

18-62

Yes

ND

(NS)

Ito 1998 [31] Otsu, Japan

NI*

30

55

>18

Yes

ND

Jutila 2012 [32] Helsinki, Finland

Prospective study

60

44

55 (30–76)

Yes

P > 0.05

Katsiari 2013 [2] Piraeus, Greece

Prospective study

30

20

47.6 ± 20.2

10–77

Yes

P = 0.01

Yes

P = 0.002

Kiyomizu 2000 [33] Miyazaki, Japan

NI*

NI*

23

36-75

Yes

ND

Kluenter 2009 [6] Fena, Germany

Prospective study

42 31–368)

52

47(11–74)

Yes

ND

Kluenter 2010 [25] Fena, Germany

Prospective study

44 (31–363)

24

51 (20–75)

Yes

ND

Krause 2009a [22] Munich, Germany

Prospective study

28 - 42

59

54 (15–83)

Yes

P < 0.001

Krause 2009b [23] Munich, Germany

Prospectivestudy

28

47

54 (16–83)

Yes

P < 0.01

Krause 2010 [24] Munich, Germany

Prospectivestudy

60

32

55 (15–83)

Yes

P < 0.001

Yes

P < 0.047

Louza 2015 [34] Munich, Germany

Retrospective observational study

28 - 42

41

>14

56 ± 19

Yes

ND

Yes

ND

Melvin 2009 [5] Johns Hopkins, Maryland, USA

Prospective cohort

28 - 42

16

46

(23–69)

Yes

ND

Yes

ND

Yes

ND

Migliaccio 2005 [10] Johns Hopkins, Maryland, USA

Prospective study

28 - 42

16

46 (27–64)

Yes

P > 0.05

Nordfalk 2014 [21] Oslo, Norway

Prospective pilot

28 - 42

12

32-61

Yes

ND

Nordfalk 2015 [19]

Oslo, Norway

Prospective

42-56

39

57.5 ± 17.2

(18–83)

Yes

ND

Yes

ND

Robard 2015 [11] Caen, France

Prospective study

150

34

49 ± 25

(1–86)

Yes

P = 0.0015

Rossi 1998 [35] Turin, Italy

Case series

180

32

12-74

Yes

ND

Todt 2008 [36] Berlin, Germany

Retrospective cohort

42 - 56

62

17-84

Yes

ND

Yes

ND

Vankatova 2014 [9] Geneve, Switzerland

Retrospective study

NI*

50

15-72

Yes

ND

Yes

ND

Wagner 2010 [17] Berlin, Germany

Retrospective cohort

42 - 56

20

41.5 (11–58)

Yes

ND

Yes

ND