Table 3 Results of the three hierarchical non-linear models of risk factors for AOM

Severe suture restriction of the temporal bone (Yes)

2.01 (1.25 to 2.69)*

<0.01

2.10 (1.41 to 2.83)*

<0.01

2.26 (1.43 to 2.91)*

<0.01

Internal rotation of the temporal bone (Yes)

1.22 (0.41 to 2.40)

0.68

0.86 (0.19 to 2.34)

0.81

0.84 (0.12 to 2.58)

0.83

External rotation of the temporal bone (Yes)

0.78 (0.31 to 1.64)

0.56

0.47 (0.15 to 1.24)

0.14

0.42 (0.13 to 1.14)

0.09

Age

0.29 (0.11 to 0.72)*

<0.01

0.25 (0.11 to 0.51)*

0.001

0.22 (0.10 to 0.52)*

0.001

Gender (Boy)

1.30 (0.65 to 2.12)

0.42

1.58 (0.84 to 2.39)

0.14

1.52 (0.82 to 2.30)

0.16

Use of pacifier (Yes)

2.47 (1.49 to 3.12)*

<0.01

2.59 (1.51 to 3.22)*

<0.01

History of upper respiratory tract infection (Yes)

0.34 (0.08 to 1.15)

0.09

0.36 (0.08 to 1.32)

0.14

Breastfeeding ≥ 6 months

0.77 (0.35 to 1.46)

0.45

0.73 (0.29 to 1.53)

0.45

Sphenobasilar synchondrosis perturbation (Yes)

1.56 (0.83 to 2.37)

0.15

1.64 (0.90 to 2.42)

0.09

Asymmetry of the occipital condylar parts (Yes)

0.97 (0.48 to 0.68)

0.93

1.01 (0.50 to 1.74)

0.98

Parental smoking (Yes)

0.66 (0.19 to 1.71)

0.44

Daycare (Yes)

1.73 (0.90 to 2.58)

0.09

Socioeconomic status (<$30,000 / year)

1.99 (0.93 to 2.90)

0.07