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Donor Selection Criteria. Dr. Mindy Goldman Transfusion Medicine Residents May 24, 2011. Plan. Importance of donor criteria Current donor screening and deferrals Factors affecting donor responses Evolution of donor criteria Assessment of questionnaire, criteria Anonymous donor survey.
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Donor Selection Criteria Dr. Mindy Goldman Transfusion Medicine Residents May 24, 2011
Plan • Importance of donor criteria • Current donor screening and deferrals • Factors affecting donor responses • Evolution of donor criteria • Assessment of questionnaire, criteria • Anonymous donor survey
RECIPIENT SAFETY DONOR SAFETY PUBLIC PERCEPTION DONOR CRITERIA DONOR SATISFACTION OPERATIONAL EFFICIENCY BLOOD AVAILABILITY
Donor screening • Donor vital signs • Donor hemoglobin (Hgb) • Donor assessment questionnaire (DAQ) • Questions 1-13 self-administered • Questions 14-30 administered by staff • 87 items queried • Identical for 1st time, repeat donors
Donor deferrals, 2010 ~ 14% of donors deferred on clinic
Indefinite deferrals 4% of deferrals are indefinite
Donor selection vs testing 100% Utility of donor selection 10% 0 1 2 3 Laboratory Test, generation
Factors affecting donor responses • Donor characteristics • Language comprehension • Memory • Motivation
Factors affecting donor responses • Mode of administration • Self-administration • Face-to-face interview • Computer administered • Privacy • Formulation and order of questions
Components of response • Comprehension • Retrieval • Judgement • Selecting and reporting answers
Evolution of donor criteria • Developed over time as new knowledge, threats emerged • Many FDA, Health Canada requirements • Little validation that question formulation elicits appropriate information • Differences across jurisdictions demonstrates not based on scientific data
Methods of assessment of criteria • Impossible to do a randomized, controlled trial • Difficult to isolate the effect of an individual criteria • Difficult to choose appropriate outcome measure • Difficult to prove that there will be “zero risk increase” for recipients or donors with a given change in criteria
Methods of assessment, donor questionnaire • Surveys of undeclared, reportable risks • Operational outcome measures • Post-donation information • Cognitive research methods • Degree of correlation, alternative wording • Qualitative methods such as focus groups
Methods of assessment, donor questionnaire • Evaluation of donor recall of items queried • DAQ in various formulations and modes of administration • Self-administered • Audiovisual computer-assisted format
Assessment of changes, recipient safety • Rates of transmission of HIV, hepatitis are too low to measure changes, risk modelling can be done • Perform TD testing in deferred donors • Assess risk factors, TD positive donors • Perform donor surveys to estimate anticipated donor loss/gain • Follow TD marker rates after making a change • Experience in other countries
Recipient safety criteria • Some successful changes • Removal of the question about fever and headache in the week before donation for WNV • Shortening of deferral period from 12 to 6 months for tattoo, piercing, needle-stick injury
Recipient safety criteria • Some challenges • Question and deferral for having sex with someone whose sexual background you don’t know • Intranasal cocaine use • Indefinite deferral for men who have sex with men, even once since 1977
Assessment of changes, donor safety • Analysis of adverse events, current criteria • Adverse effects in autologous donors • Experience in other countries • Increase surveillance after changing criteria
Donor safety criteria • Some successes • Acceptance of donors on antihypertensive medications • Acceptance of donors with celiac disease • Increase in upper age limit
Donor safety criteria • Some challenges • Optimal criteria to prevent donor iron deficiency • More stringent height and weight criteria for younger donors • Donor pulse rate and regularity • Donors on insulin
Anonymous donor survey • Anonymous questionnaire mailed to 40,000 whole blood donors monthly in 2008, 2-6 weeks post donation • Sample stratified by region • First-time donors over-sampled to constitute 50% of sample • 45.5% response rate
Anonymous donor survey • How would alternate questions for HIV affect donor deferral rates • How would deferral of donors with severe peanut allergies impact blood availability • Does donor height and weight affect reaction rate
Donor reactions • Donors asked if they had any symptoms at the time of donation or following donation • Asked height, weight, gender, and age • Estimated blood volume (EBV) can be calculated based on height, weight, and gender • EBV < 3.5 litres associated with increased reactions in US
Correlation of self-reported EBV and adverse reactions, 2008 donor survey
Correlation of self-reported EBV and adverse reactions, 2008 donor survey
Summary • Donor criteria play an important part in ensuring donor and recipient safety, adequacy of supply • Approximately 14% of donors are deferred on the clinic, 4% of donors are deferred indefinitely • Many factors affect donor responses to screening questions
Summary • Evaluation of the donor questionnaire, and criteria to protect recipients or donors is challenging • At CBS, we have attempted to obtain data on possible changes in donor eligibility through the use of an anonymous donor survey