Additional file 2: of A comparison of the quality of image acquisition between the incident dark field and sidestream dark field video-microscopes

Two examples of images obtained using the sidestream dark field video-microscope. (PNG 1188 kb

Ethnic differences in anthropometric measurements in boys.

<p>Dots represent mean values, error bars represent standard error of the mean. <i>Black African/Caribbean</i> boys generally had higher mean values of all circumferences and standing height, but lower sitting/standing height ratio, at each age group as compared to <i>White</i> and <i>South Asian</i> children. An increasing trend for ethnic differences in body circumferences is evident, especially after 9 years of age. Despite its heterogeneity, the ‘<i>Other</i>’ group tend to track <i>White</i> and <i>South Asian</i> group more closely than <i>Black African/Caribbean</i> group. Similar pattern was observed in girls (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0113883#pone.0113883.s003" target="_blank">Figure S3</a>). Due to relatively small sample size >10 years old (n = 12) the estimates may be biased therefore the trend lines from 10 to 11 years old were replaced by dotted lines.</p

Conceptual illustration for deriving the ‘best’ BIA equation.

<p>Calibration equations aim to describe the relationship between fat-free mass (FFM) and height²/impedance (HT²/Z) or impedance (Z). Three types of calibration equations were investigated: (i) a generic equation with no ethnic terms; (ii) a simple ethnic-specific equation (same slope, different intercept); (iii) a complex ethnic-specific equation with ethnic-impedance interaction terms (different slopes, different intercepts). Model can have very similar average residuals but the distribution of residuals may vary across ethnic groups (iv). To avoid ethnic bias, models with even residual distribution (v) are preferred.</p

Residuals distribution for each ethnic group for model A2.

<p>Residuals from model A2 were regressed, for each ethnic group, on height²/impedance as indicated by the bold regression line. The shaded area represents a 95% confidence interval for the mean of residuals as a function of height²/impedance. Correlation coeffients (95% confidence interval) are also shown. No mean, and no slope, differed significantly from zero.</p

Background characteristics of the study populations.

<p>Data presented as mean (SD) unless otherwise stated.</p>#<p>Height, weight and body mass index were adjusted for age and sex and expressed as z (or SD score) using British 1990 reference <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0113883#pone.0113883-Cole1" target="_blank">[31]</a>.</p><p>Background characteristics of the study populations.</p

Group characteristics and spirometry results (based on GLI-White equations) according to centre.

<p>Group characteristics and spirometry results (based on GLI-White equations) according to centre.</p

Spirometry data from Delhi (Centre B) and Leicester (Centre G) according to GLI-Other reference.

<p>Spirometry data from Delhi (Centre B) and Leicester (Centre G) according to GLI-Other reference.</p

Association between extreme poverty and lung function in children residing in India.

<p>Association between extreme poverty and lung function in children residing in India.</p

Summary of studies included in the collation of South-Asian data.

<p>Summary of studies included in the collation of South-Asian data.</p

Spirometry data from South-Asian subjects according to GLI-South-East Asian reference.

<p>Spirometry data from South-Asian subjects according to GLI-South-East Asian reference.</p