Table 3

Methodological quality of included trials*

Descriptive

Statistical

Internal Validity

Total Validity


Study

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

?

+


Binder, 2002

+

+

+

+

-

+

+

+

+

+

?

?

+

-

+

+

2

6


Boshuizen, 2005

+

+

-

+

-

+

+

+

?

?

?

+

+

-

+

+

3

5


Chandler, 1998

+

+

-

+

-

+

-

+

?

+

?

?

+

+

+

+

3

6


Chin A Paw, 2001

+

+

+

+

-

+

+

+

?

+

?

+

-

-

+

+

2

5


Gill, 2002

+

+

+

+

-

+

+

+

?

+

?

+

+

+

+

+

2

7


King, 2002

+

+

+

+

-

+

+

+

?

+

?

-

+

-

+

+

2

5


Kretser, 2003

+

+

-

+

-

+

+

?

-

?

?

?

?

+

+

+

5

3


Payette, 2002

+

+

-

+

-

+

+

+

?

+

?

-

+

+

+

+

2

6


Timonen, 2004

+

+

-

+

+

+

-

+

?

+

?

+

?

+

+

+

3

6


Worm, 2001

+

-

-

+

-

+

-

+

-

?

?

+

?

+

+

+

3

5


* '+' criterion fulfilled; '-' criterion not fulfilled; and '?' data not provided or unclear.

see table 2 for a detailed description of the items.

Daniels et al. BMC Health Services Research 2008 8:278   doi:10.1186/1472-6963-8-278

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