Table 2.

Linear regression model of determinates of the total number of hospital attendances between July 2022 and July 2023 amongst individuals with antibody deficiency in the Birmingham cohort

Variable	Estimate	Standard error	95% CI (asymptotic)	P value
Age	0.0672	0.0513	-0.0339 to 0.168	0.1915
Sex	2.09	1.60	-1.06 to 5.24	0.1922
Secondary antibody deficiency	5.33	1.80	1.79 to 8.86	0.0033
Treatment with IVIG	13.5	2.10	9.37 to 17.7	< 0.0001
Treatment with SCIG	5.26	1.94	1.44 to 9.08	0.0072

Linear regression model uses sex and primary vs. secondary antibody deficiency as binary categorical variables (male sex and secondary antibody deficiency as reference levels), and immunological treatment as a three-level categorical variable with treatment with prophylactic antibiotics as a reference level