Table 1 Descriptive Statistics for Study and Communication Variables, All Studies (n = 273)

Journal Impact Factor

7.1

0.3–19.1

Sample Size

2,251

20–105,114

Abstract SMOG Index Reading Grade Level

11.1

1.8–18.5

Press Release SMOG Index Reading Grade Level

11.9

9.2–14.8

Days Between Publication and Press Release

34

0–213

Scholarly Citations

24

0-116

CATEGORICAL VARIABLE

NUMBER

PERCENTAGE

Open-Access

127

46.5%

Study Type, n (%)

 Cross sectional

133

48.7%

 Cohort

96

35.2%

 Case control

36

13.2%

 Randomized control trial

6

2.2%

 Ecological

2

0.7%

Publication Day of Week

 Monday

50

18.3%

 Tuesday

59

21.6%

 Wednesday

45

16.5%

 Thursday

48

17.58%

 Friday

39

14.3%

 Saturday

24

8.8%

 Sunday

8

2.9%

Significant Finding

 Yes

205

75%

 No

68

25%

Press Release

 Yes

17

6.2%

 No

256

93.8%