Strengths and limitations
The study was limited to 1 year. Therefore, AEs that developed,
subsequently, may be missed. Since previous studies have shown that most
(serious) AEs occur at the beginning of treatment and AEs decrease over
time from 51.8% at day 1 to 5.8% after 1 year in this study, we
consider this risk to be low.
138 out of 415 patients did not complete the study. Discontinuation of
treatment is a common problem when administering SLIT. This might have
had impact on our outcomes i.e. there could be an underestimation of the
safety and tolerability effects and an overestimation of effectiveness.
Nonetheless, no major differences were observed in baseline
characteristics of patients that continued versus those that
discontinued treatment, indicating that outcomes are representative for
all patients.