Adjusted associations of demographic, maternal, pregnancy and child characteristics with wheezing phenotypes in ALSPAC.

*<p>compared with never/infrequent wheezing (N = 5774) and using each child’s phenotype probability as weights.</p>±<p>Educated to school leaving certificate at 16 years (GCE level) or lower.</p>+<p>Chi-squared test across phenotypes.</p

Description of study samples in each period with data on wheezing phenotypes.

±<p>Educated to school leaving certificate at 16 years (GCE level) or lower.</p

Adjusted associations of perinatal characteristics with wheezing phenotypes in ALSPAC.

*<p>compared with never/infrequent wheezing (N = 5642) and using each child’s phenotype probability as weights.</p>±<p>Not adjusted for each other but adjusted for preterm delivery (<37 weeks).</p>‡<p>Not adjusted for each other and not adjusted for birth weight/low birth weight (since birth weight does not influence gestational age).</p>+<p>Chi-squared test across phenotypes.</p

Adjusted associations of postnatal characteristics with wheezing phenotypes in ALSPAC.

*<p>compared with never/infrequent wheezing (N = 4915) and using each child’s phenotype probability as weights.</p>+<p>Chi-squared test across phenotypes.</p

Estimated prevalence of wheezing at each time-point from 3.1 to 10.7 years for each of the four wheezing phenotypes identified by latent class analysis in 7349 participants with complete observations of wheeze in the last 12 months in the MCS.

<p>Estimated prevalence of wheezing at each time-point from 3.1 to 10.7 years for each of the four wheezing phenotypes identified by latent class analysis in 7349 participants with complete observations of wheeze in the last 12 months in the MCS.</p

Male odds ratios for ever wheeze, ever asthma and wheeze in the last 12 months in the MCS at 4 time-points.

<p>Male odds ratios for ever wheeze, ever asthma and wheeze in the last 12 months in the MCS at 4 time-points.</p

Characteristics of wheeze and asthma outcomes in the MCS by sex, with follow-up rates at each time-point as a percentage of total cohort size for each sex (total MCS = 8850 males and 8458 females).

<p>Characteristics of wheeze and asthma outcomes in the MCS by sex, with follow-up rates at each time-point as a percentage of total cohort size for each sex (total MCS = 8850 males and 8458 females).</p

Male odds ratios for wheeze in the last 12 months and asthma in the last 12 months, in ALSPAC.

<p>Male odds ratios for wheeze in the last 12 months and asthma in the last 12 months, in ALSPAC.</p

Characteristics of wheeze and asthma outcomes in ALSPAC by sex, with follow-up rates at each time-point as a percentage of total cohort size for each sex (total ALSPAC = 7,544 males and 7,155 females).

<p>Characteristics of wheeze and asthma outcomes in ALSPAC by sex, with follow-up rates at each time-point as a percentage of total cohort size for each sex (total ALSPAC = 7,544 males and 7,155 females).</p

Concepts of (A) confounding and (B) mediation in epidemiological studies illustrated using a Directed acyclic graph (DAG).

<p>In the case of sex and asthma, where sex is the exposure and asthma status the outcome, any extraneous factors must go by the mediation pathway, as nothing can influence a child’s sex at conception.</p