To assess the effect of current weight on BWD, the entire sample was
categorised into the WHO BMI categories of underweight (b18.5), normal
weight (18.5–24.99), overweight (25.0–29.99) and obese (≥30)
(World Health Organization, 2006). BWD was compared between the
ED and the Control groups within each of these four weight categories
using Mann–Whitney U tests.
To assess the effect of purging, the ED group was divided into
women with self-reported symptoms of purging and women without
symptoms of purging. Purging was defined as the presence of selfinduced
vomiting or laxative abuse at least once a week during the
previous three months. The variables were compared between the
purgers and non-purgers within each of the four BMI categories using
non-parametric Mann–Whitney U tests.
p values less than 0.05 were considered to indicate statistical
significance.
3. Results
3.1. Demographics
Demographic information is provided for the Control and ED groups
in Table 1. There was no difference in the age, nulliparity or proportion
of subjects with a Caucasian mother between the two groups. There was
a higher proportion of never married women in the ED group compared
to the Control group (p = 0.007).
3.2. Correlation between measures of body dissatisfaction
All three measures (BWD, Body Appearance rating and Body Image
score) were statistically significantly correlated, with a positive correlation
between BWD and the Body Image score (such that greater BWD
was correlated with higher scores on the Body Image score; rs = 0.42,
p b 0.001; N = 1149); a negative correlation between BWD and the
Body Appearance rating (such that better perceptions of Body Appearance
on the scale from 0 to 10 were associated with lower levels of
BWD; rs = −0.37, p b 0.001; N = 1150). There was a strong negative
correlation between the Body Image score and the Body Appearance