Table 1 Table of characteristics of reports presented by methodological quality or both methodological and reporting quality

Year of publication

1993–2009

26 (52)

11 (42)

37 (49)

2010–2014

23 (46)

16 (62)

39 (51)

Number of assessed SRs

Median (IQR)

43 (21, 88)

68 (36, 109)

51 (25, 105)

Range

10–327

10–487

10–487

Were SRs of particular medical field?

Yes

45 (90)

21 (81)

66 (87)

No

5 (10)

5 (19)

10 (13)

Cohort of Cochrane SRs

Cochrane only

2 (4)

3 (12)

5 (7)

Sample of reviews

23 (46)

10 (38)

33 (43)

Specific journal sample or other

25 (50)

13 (50)

38 (50)

Number of databases searched

1

9 (18)

8 (31)

17 (22)

2

5 (10)

2 (8)

7 (9)

3

7 (14)

2 (8)

9 (12)

4

7 (14)

5 (19)

12 (16)

5

5 (10)

3 (12)

8 (11)

6

2 (4)

2 (8)

4 (5)

7

5 (10)

1 (4)

6 (8)

8+

3 (6)

1 (4)

3 (4)

Not reported

4 (8)

0 (0)

4 (5)

Not applicable (select journals)

3 (6)

3 (12)

5 (7)

Reports restricting SRs by language

No restrictions

14 (28)

6 (23)

20 (26)

Restricted to English

14 (28)

4 (15)

18 (24)

Restricted to English and another specified languages

4 (8)

3 (12)

7 (9)

Not reported

18 (36)

13 (50)

31 (41)

SR defined for inclusion criteria?

Yes, but no reference given

5 (10)

6 (23)

11 (15)

‘Systematic review’ reported as a search term

21 (42)

12 (46)

33 (43)

Cochrane collaboration and PRISMA Statement

4 (8)

5 (19)

9 (12)

Other reference

3 (6)

0 (0)

3 (4)

Not reported

17 (34)

3 (12)

20 (26)

Was a study protocol reported as available for this report?

Yes, link reported

1 (2)

2 (8)

3 (4)

Yes, upon request

6 (12)

2 (8)

8 (11)

No or not reported

43 (86)

22 (85)

65 (86)

Report Source of funding

Industry Funded

2 (4)

0 (0)

2 (3)

Non-profit Funding

21 (42)

14 (54)

35 (46)

Reported no funding

6 (12)

3 (12)

9 (12)

Not reported

21 (42)

9 (35)

30 (39)