Table 4

Pacifier use for the last/reference sleep stratified by age, socioeconomic status, breast feeding duration, and maternal smoking after pregnancy

Infant age4-150 Proportion of infants who used a pacifier for the last/reference sleep
SIDSControls
n%n%
 0–8 weeks24/8528.2134/29245.9
 9–14 weeks35/8541.2173/35448.9
 15–22 weeks35/7546.7162/30153.8
 23 weeks or older30/6844.1195/34955.9
 χ2test for trendp < 0.05p < 0.001
 Test for departure from linearity0.25 > p > 0.100.90 > p > 0.75
 Mantel-Haenszelp < 0.001
Socioeconomic status n % n %
 V or never employed34/6750.761/9266.3
 III or IV74/19737.6409/75953.9
 I or II16/4833.3193/44243.7
 χ2 test for trendp < 0.05p < 0.001
 Test for departure from linearity0.50 > p > 0.250.90 > p > 0.75
 Mantel-Haenszelp < 0.001
Duration of breast feeding4-160 n % n %
 Never attempted81/17945.3319/52261.1
 1–2 weeks16/4040.0100/16959.2
 3–6 weeks13/4131.792/18948.7
 7–12 weeks8/2927.681/20339.9
 More than 12 weeks6/2425.071/21233.5
 χ2 test for trendp < 0.01p < 0.001
 Test for departure from linearity0.75 > p > 0.500.25 > p > 0.10
 Mantel-Haenszelp < 0.001
Maternal smoking n % n %
 Does not smoke33/10332.0450/92948.4
 1–9 cigarettes30/8535.376/15748.4
 10–19 cigarettes38/7054.394/14465.3
 20 or more cigarettes23/5541.844/6567.7
 χ2 test for trendp < 0.025p < 0.001
 Test for departure from linearity0.10 > p > 0.050.25 > p > 0.10
 Mantel-Haenszelp < 0.001
  • Maternal smoking referes to maternal smoking after pregnancy.

  • 4-150 Using approximate 25th, 50th, and 75th centiles of whole data set as a cut off.

  • 4-160 Using approximate 25th, 50th, and 75th centiles of all breast feeders as a cut off.