The following guide draws from the experiences of the US Centers for Disease Control & Prevention, Kaiser Permanente, and Code for America's GetCalFresh project.
1) The CDC’s Guide to Writing for Social Media 2012
Be Clear and Concise:
Use easy-to-understand language.
Catch the reader’s attention with a compelling lead that provides the most important information first.
Abbreviations are necessary in a 160-character message, but try to use them sparingly. Try to use commonly-understood abbreviations.
Have a clear call to action, encouraging people to take concrete steps.
Explain why the action is important.
Use strong verbs such as “learn,” “watch,” or “join.”
Be Useful and Relevant:
Send messages that are tied to current events, seasons, or observance days.
Provide concrete knowledge and additional resources.
Use Web Content as a Source of Material:
News articles, fact sheets, and FAQs are excellent sources of additional material.
Web content has often been developed, edited, and cleared through the proper channels.
Just be sure to rework your web content so it makes sense over text.
Customize your Texts:
The CDC asks contacts questions about themselves to better target their messages.
Questions include age, gender, health condition, subscriber’s role, and zip code.
Identify Yourself: You should always identify yourself in your text, so your subscribers know who the text is from.
Provide Access to More Information:
Include a phone number or URL in your message, so contacts can follow up.
Make sure all numbers are numerical and formatted, so readers can click to call.
2) CDC: Social Media Guidelines and Best Practices (2010), Sample Messages
"Test your smoke alarms and carbon monoxide detector when u turn your clocks back on Nov 1; replace batteries if needed. Call CDC 800-232-4636 or http://m.cdc.gov."
"Cover cough & sneezes to protect others. Call CDC 800-232-4636 or http://m.cdc.gov for more info. Reply HEALTH QUIT to end."
"Spread the word! Tell friends & family to text 4HEALTH to 87000 to get these weekly H1N1 messages & impt health tips. Call CDC 800-232-4636 or http://m.cdc.gov"
"Thanksgiving is Nat'l Family History Day. Talk to UR family about health conditions that run in UR family. Learn more http://m.cdc.gov/family. CDC 800-232-4636"
3) Kaiser to Roll out Text Messaging Appointment Reminders (2009), Lessons Learned
Generic appointment reminders are more effective than specific ones: Mammogram appointment reminders that specified the test had a 2.96 percent unsubscribe rate, for example.
Patients aged 13 to 17 years old and 18 to 24 years old have the highest opt-out rate probably because they know how to opt-out.
4) Additional Tips
Don’t have people draw inferences of what to do. Give them an action they can take. Ex.: “CalFresh (Food Stamps): You may stop receiving benefits at the end of the month. Questions? Call (555) 555-5555.”
Testing with contacts/recipients of text messages should occur at least twice prior to deployment.