The Effect of Message Framing on Blood Donation-Study 1

Study Overview
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Brief Summary
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Rh negative blood group is a rare blood group in China, as it only accounts for 0.3-0.4 percent of the Han population. Therefore, low inventory is often found in blood collection and supply agencies in many regions in China. On July 18, 2018 blood stockpile of O-negative and B-negative in Guangzhou Blood Center reached the warning line, and we took measures for emergency recruitment. O-negative and B-negative blood donors whose last donation dates were between January 1, 2015 and December 31, 2017 were identified and randomly assigned to three groups. Three different recruitment text messages were send to these groups respectively. At the same time, A-negative and AB-negative blood donors were marked as control group. We observed the re-donation rates among four groups within three months.

Official Title
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Saving a Life or Preventing a Death: the Effect of Message Framing on Blood Donation Among Rh Negative Donors

Conditions
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Rh Negative Blood Donor

Intervention / Treatment
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* Other: Gain-frame SMS
* Other: Loss-frame SMS
* Other: Control SMS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Rh- negative blood donors whose last donations were between January 1, 2015 and December 31, 2017. Exclusion Criteria: Donors with an obviously invalid phone number. Donors whose serological results of the last donation were positive.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Gain-frame SMS<br>SMS messages Dear Rh negative blood donors: Hello! As the Rh negative O/B blood stockpile is low now, but patients who are this blood type are in urgent need. If you are available, we hope that you can offer a helping hand to save their lives. Thank you for your support. were send to donors in this group. | Other: Gain-frame SMS<br>* Emergency recruitment cell phone short messages that emphasizing donating blood can save patients' lives were sent to donors in this group.<br>|
| Experimental: Loss-frame SMS<br>SMS messages Dear Rh negative blood donors: Hello! As the Rh negative O/B blood stockpile is low now, but patients who are this blood type are in urgent need. If you are available, we hope that you can offer a helping hand to prevent them from death. Thank you for your support. were send to donors in this group. | Other: Loss-frame SMS<br>* Emergency recruitment cell phone short messages emphasizing that donating blood can prevent patients from death were sent to donors in this group.<br>|
| Experimental: Control SMS<br>SMS messages Dear Rh negative blood donors: Hello! As the Rh negative O/B blood stockpile is low now, but patients who are this blood type are in urgent need. If you are available, we hope that you can donate blood again. Thank you for your support. were send to donors in this group. | Other: Control SMS<br>* Emergency recruitment cell phone short messages that only mentioning the low Rh-negative blood stockpile were sent to donors in this group.<br>|
| No Intervention: Control group<br>Donors in this group were not received SMS reminders. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Re-donation rate | Intention-to-treat were applied. Re-donation rate was defined as the number of donors in each group devided by donors who re-donated within 3 months. | 3 months |