Table 3

Adverse events reported in observational studies

Adverse event

Number of studies

References

N of events

Pooled n

Proportion

95% CI

τ²

Headache

17

[75,93,110,118-120,123-125,127-129,131,136,138,140,141]

1472

75764

9.7

4.6-19.5

2.97

Nausea or vomiting

14

[75,110,119,120,123,124,128,129,136-138,140,141]

1902

74449

8.5

4.6-15.3

1.39

Gastrointestinal complaints

11

[110,118,120,123,127,129,131,136,138,140,141]

593

74256

3.9

1.4-10.4

3.02

Heart palpitations

7

[75,120,122,127,131,136,141]

72

2446

3.6

1.4-9.0

1.49

Mouth and throat soreness

6

[125,129,135-137,140]

406

72533

5.4

0.9-25.6

5.00

Skin irritation

16

[75,93,118-124,126-129,131,138,141]

1337

10356

19.5

11.5-31.1

1.56

Hiccoughs

4

[129,136,137,140]

375

71948

2.5

0.3-16.5

4.63

Coughing

5

[120,125,128,135,136]

125

1672

8.1

2.1-26

2.29

Depression

6

[110,120,124,138,140,141]

69

66344

2.6

0.2-27

10.57

Anxiety

5

[118,120,129,138,141]

104

5841

2.9

0.8-9.8

1.70

Insomnia

18

[75,110,118-123,125-129,131,138,140,141]

2262

76169

11.4

4.8-24.6

4.05

Dizziness

8

[110,118,120,124,127,129,136,141]

299

7338

7.3

3.7-13.9

0.94

Self-harm

1

[110,118,120,124,127,129,136,141]

141

63265

0.2

0-8.4

NA

Mills et al. Tobacco Induced Diseases 2010 8:8   doi:10.1186/1617-9625-8-8