A phone call asking lapsed donors to come got more to give blood

Helped
A short phone call asking lapsed donors to say they'd come got 23 in 100 to give blood, against 13.
- Rule: Ask someone to expect youtested
- Action: Donate bloodused
Large randomised trial of 1,400 lapsed blood donors in Zurich, Switzerland · vs people who got only the usual letter and text · behaviour was recorded
Helped
People who got one call still gave blood more often 6 and 12 months later, but not 18 months later.
- Rule: Ask someone to expect youtested
- Action: Donate bloodused
Large randomised trial of 1,400 lapsed blood donors in Zurich, Switzerland · vs people who got no phone call · behaviour was recorded

The study

Who took part

1,400 people in Zurich, Switzerland, who were signed up to give blood but had not come in the past year. They were about 41 on average, about half were men, and all had blood types O+, O- or A-.

What they did

Two days before a blood drive, staff phoned people. They asked, "Can I put you down as attending?". Some got this call in the first six months, some in the next six months, and some in both. The other group got only the usual letter and a text the day before.

What happened

In the six months of the call, about 23 in 100 called people gave blood. In the other group, about 13 in 100 did. More of the called people still gave blood 6 and 12 months later, but not 18 months later.