【Objective】 To study the demographic characteristics of whole blood donors aged 56 to 60 in Guangzhou, so as to provide reference for smooth implementation of the recruitment and management of elderly blood donors in Guangzhou. 【Methods】 The data of whole blood donors, aged 56 to 60, in Guangzhou Blood Center from July 1, 2016 to June 30, 2021 were retrospectively analyzed, and such characteristics as the number of blood donations, gender, donation frequency, donation volume, occupation and educational background were analyzed. 【Results】 A total of 3 996 blood donors aged 56 to 60, including 3 013 males and 983 females, gave 14 416 donations during July 1, 2016 to June 30, 2021, with the proportion of 400 mL specification at 64.1% (6 999/10 918) of males, which was significantly higher than that of females 57.7% (2 017/3 498). The number of blood donors had been decreasing year by year, but the ratio of men to women was stable.The education background of blood donors were mainly high school, junior college, and undergraduate education, accounting for more than 60% in total, and the proportion of undergraduate and graduate degree trended to grow. Staff, workers, medical staff and civil servants were the majorities, and the proportion of medical staff trended to grow. 【Conclusion】 Male blood donors aged 56 to 60 in Guangzhou showed stronger intention to donate blood, and the proportion of blood donors with better education and medical staff was on the rise.

【Objective】 To investigate the changes of platelet, white blood cell, red blood cell counts, Hb and PCV before and after plateletpheresis donation. 【Methods】 10 444 platelet donors who donated platelet from Aug 1, 2019 to Jul 31, 2020 were selected as subjects, among which first-time donors were selected as control group and donors who donated twice or more as donation group. After matching gender and age using Propensity Score Matching method in the two groups, the changes of platelet, white blood cell, red blood cell counts, Hb and PCV of platelet blood donors were compared by t test. 【Results】 There were a slight increase in Plt (t=-6.651, P<0.05), a decrease in WBC (t=2.312, P<0.05), a decrease in hemoglobin(t=4.643, P<0.05), and no change in RBC (t=1.439, P>0.05) and in PCV (t=0.030, P>0.05) after plateletpheresis donation. 【Conclusion】 Plateletpheresis donation has an effect on some peripheral blood parameters, but within the normal reference range.

【Objective】 To investigate the prevalence of depression in blood donors and analyze the related factors, so as to develop a rapid depression screening model for blood donors. 【Methods】 A total of 13 015 street whole blood donors in Guangzhou Blood Center during May to August, 2020 filled in an anonymous e-questionnaire, including social demography information and the Patient Health Questionnaire-9 before donation. The cut-off value for detecting depression was 10. Logistic regression by SPSS 26.0 was used to analyze depression related factors. 2-level decision tree with 30/10 as the minimum number of cases in parent/child node, 10-fold cross validation was used to cut items of PHQ-9 to form the depression screening model. 【Results】 364 out of 13 015 (2.80%) street whole blood donors reported a score ≥ 10. Donors with 18-29 years old (P <0.05), unmarried (P<0.05), less than 50 000 RMB household income per year (P< 0.05) were more prone to depression. 81.96% donors in "<10 scores" group, while 3.85%donors in "≥ 10 scores" group were in two terminal nodes formed by Item-6, 2 and 4 of PHQ-9. After verification by the 10 fold crossover method, the estimated misclassification risk of the model was 1.7%. 【Conclusion】 The screening prevalence of depression based on PHQ-9 in Guangzhou blood donors was 2.8%(95% CI: 2.52%-3.09%) . Donation frequency was not related to depression. A rapid and efficient depression screening model for blood donors based on item-6, 2 and 4 of PHQ-9 was developed.