Statistical analysis
Continuous variables were expressed in terms of mean, median, standard
deviation and range. Categorical variables were presented using
frequency and percentages. Chi-square test was used to compare severe
infection, infection involving respiratory system, infection involving
systems other than respiratory system, between children with normal
immunoglobulin levels and hypoglobulinaemia and different age groups and
risk groups. Logistic regression analysis was performed to find the risk
of severe infection with respect to different parameters. P-value
<0.05 was considered as significant.