Characteristics of the instrument
The Italian version of CVID-QoL is developed by Quinti et al. in 201510. It consists of 32 items that are most predictive
of self-care behaviours, patients’ aspects of the Ig replacement therapy
and the features of CVID. The questionnaire is designed to review the
situation for the last 3 months. The instrument is a 5-point-likert
scale with 0= “never”, 1= “rarely”, 2= “sometimes”, 3= “often”
and 4= “always” with higher values generally indicating increasing
disability. Total score ranges from 0 (minimum score) to 128 (maximum
score); higher scores indicate poorer QoL. It was also identified in
percentages as the ratio of the QoL score to the maximum score.