Association of different risk factors with wheeze ever in white children aged one year (unadjusted).

<p>ETS: environmental tobacco smoke</p><p>*Attack group: "Did she smoke in the year this child was born?"; Whistling group: "Did she smoke during the pregnancy with this child?"</p><p>^† The categories cover the following Townsend Deprivation Index intervals: more affluent: [-6.222, -1.397]; average: [-1.396, 2.828]; more deprived: [2.829, 11.072]; We used a likelihood-ratio test to calculate the p-value for interaction for this variable</p><p>^‡ Age at end of education >16 years (mother or father)</p><p>Association of different risk factors with wheeze ever in white children aged one year (unadjusted).</p

Prevalence of indicators of wheeze severity (white children).

<p>^† Chi squared tests</p><p>Prevalence of indicators of wheeze severity (white children).</p

Crude and adjusted odds ratios for respiratory symptoms in white children.

<p>The odds ratios compare the whistling group to the attack group (adjusted for sex, exact age, breast feeding, nursery care, number of siblings, pre- and postnatal exposure to environmental tobacco smoke (ETS), parental asthma and parental hay fever, Townsend score (an area-based deprivation measure) and parental education). The error bars denote 95% confidence intervals.</p

Prevalence of wheeze and other respiratory symptoms (white children).

<p>*A few questionnaire items had different wording in the two groups. Among them was the question about wheeze ever: Attack group: "Has your child ever had attacks of wheezing?"; Whistling group: "Has your child ever had wheezing or whistling in the chest at any time in the past?" Based on this, the groups were labeled "attack group" and "whistling group".</p><p>^† Chi squared tests</p><p>Prevalence of wheeze and other respiratory symptoms (white children).</p

Comparison of clinical and perinatal attributes between clustered^* and nonclustered cases of CL both unadjusted and adjusted for local child population density.

<p>Comparison of clinical and perinatal attributes between clustered^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0170020#t002fn002" target="_blank">*</a>} and nonclustered cases of CL both unadjusted and adjusted for local child population density.</p

Frequency of individual CL clusters by cluster size in the empirical and 999 Monte Carlo samples.

<p>Frequency of individual CL clusters by cluster size in the empirical and 999 Monte Carlo samples.</p

Results of Knox tests of cases of leukemia at place and time of birth of children 0–15 years of age.

<p>Results of Knox tests of cases of leukemia at place and time of birth of children 0–15 years of age.</p

Flow chart of study population.

<p>Flow chart of study population.</p

Characteristics of the study population in 1998 (N = 6808).

<p>Characteristics of the study population in 1998 (N = 6808).</p

Prevalence of cough in different age groups in the entire cohort, and separately for children with and without wheeze.

<p>Prevalence of cough in different age groups in the entire cohort, and separately for children with and without wheeze.</p