Questionnaires

The questionnaire for DIS-I (PDF, 94 kB) was self-administered, mainly multiple choice and comprised 102 items in Dutch. During DIS-II, the same, slightly updated questionnaire (PDF, 563 kB) was used. Six topics were covered in the questionnaire.

DIS-I & DIS-II

TopicSubjects
Demographic characteristicsHousehold, ethnicity, education and employment.
DonationExperiences with the blood bank and blood donation, including short-term effects and a very broad assessment of potential motivators for and barriers to blood donation.
LifestyleDiet, smoking, alcohol use, physical activity and travel behaviour.
Health and diseaseHealth status, medication use and medical history.
Family compositionInformation on family composition and family members giving or receiving blood was collected in detail. Data on cancer, myocardial infarction and stroke events in the family were also collected.
Psychological constructsSuch as the Theory of Planned Behaviour (TPB), based on previously published measures and concepts such as trust and altruism.
FemalesInformation concerning menstruation pattern, contraceptive use, menopause, reproductive organ surgery and pregnancies.

DIS-III

TopicSubjects
LifestyleInternational physical activity questionnaire (IPAQ), short version of Food Frequency Questionnaire (FFQ), smoking, alcohol use and medication use.
Symptoms associated with iron deficiencySF-12 (general health), restless legs syndrome, cognitive functioning, pica, fatigue
Femalesnformation concerning menstruation pattern, contraceptive use, menopause, reproductive organ surgery and pregnancies.