Variables	Statistical significance	Effect size
	P-value	Phi/Cramer’s V
Sex
Have you donated blood in the past?	.04	.14 (Small to moderate)
Frequency of blood donation?	.84
How many years have you been a blood donor?	.03	.16 (Small to moderate)
Reason for donating blood for the first time?	.31
Reason for today's blood donation?	.44
Do you have a volunteer blood donor card?	.70
Age
Have you donated blood in the past?	.00	.25 (Medium to large)
Frequency of blood donation?	.28
How many years have you been a blood donor?	.00	.35 (Large)
Reason for donating blood for the first time?	.65
Reason for today's blood donation?	.02	.17 (Small to moderate)
Do you have a volunteer blood donor card?	.00	.24 (Medium to large)
Marital status
Have you donated blood in the past?	.13
Frequency of blood donation?	.04	.16 (Small to moderate)
How many years have you been a blood donor?	.00	.19 (Medium to large)
Reason for donating blood for the first time?	.09
Reason for today's blood donation?	.48
Do you have a volunteer blood donor card?	.43
Educational level
Have you donated blood in the past?	.20
Frequency of blood donation?	.82
How many years have you been a blood donor?	.53
Reason for donating blood for the first time?	.31
Reason for today's blood donation?	.94
Do you have a volunteer blood donor card?	.83
Employment status
Have you donated blood in the past?	.08
Frequency of blood donation?	.46
How many years have you been a blood donor?	.01	.17 (Medium to large)
Reason for donating blood for the first time?	.44
Reason for today's blood donation?	.02	.17 (Small to moderate)
Do you have a volunteer blood donor card?	.28
Daily working hours
Have you donated blood in the past?	.09
Frequency of blood donation?	.71
How many years have you been a blood donor?	.09
Reason for donating blood for the first time?	.68
Reason for today's blood donation?	.19
Do you have a volunteer blood donor card?	.33