Observing and recording well-defined events
Administering surveys with closed-ended questions
A checklist (of the procedure of infusing immunoglobulins at home).
Observation of the effectiveness of the method of infusing immunoglobulins at home.
Questionnaires for the patients and nurses to fill in.
Medical records (to quantify the number of infections that present in the period of the 2 years that the research study runs, as well as to ascertain the infectious organism in each case.