Consideration of your audience's needs and preferences using direct input or
relevant published studies is important when developing a text messaging
intervention. You will want to consider how many messages to send and how often,
as well as the most effective message content. We recommend designing messages
carefully according to the desired outcomes using a theory-driven, and using an
evidence-based approach to text messaging intervention development. You can
learn more about communication theory and developing message content by
referring to the Develop a Communication Strategy section and other sources
listed in the Useful Links and Resources section.
Another factor to consider is maintaining participants’ privacy. Laws and
regulations regarding patient privacy apply to text messaging in healthcare.
Although text messages are encrypted during transfer, a message that displays on
a screen may be visible to people close by and accessible to people who have
access to a user’s phone. Researchers can protect patient privacy by restricting
the amount of information in messages or advising research participants to
protect their cellphones with passwords and settings that restrict the amount of
information delivered with a text message receipt notification. Additionally,
participants can use antitheft applications that allow them to remotely lock
their phone and wipe it clear of sensitive information.
The public has a choice in what messages they receive. SMS applications allow
for people to either opt-in or to opt-out. The universal method of opting out of
a program is to respond with the keyword "STOP." Opt-in options require active
acceptance by texting a code word, such as "EATWELL" for a program to deliver
daily nutrition tips, to a predetermined short code. Opt-in programs require
advertising or outreach to the target audience that would also include the short
code and the code keyword so they know how to opt-in. If you are sending
messages to a predetermined list, an opt-out feature may be the best option. See the Security and Privacy section for a complete list of applicable regulations and best practices.