Table 3.

Comparison of key aspects of message optimization.

Aspects of message optimization		Pilot study	Main study
Message content
	Themes	A broad scope of information, including management of metabolic risk factors, medication adherence, tobacco and alcohol control, dietary change, physical activity, and psychological recovery	Focused on medication adherence and physical activity and supplemented with other information on metabolic risk factor management and stroke in general
	Structure	Random structure for each message	Same structure for all messages: program name + reminder sentence + health education information
	Key information	Multiple key information within 1 message	Single key information for 1 message
	Languages	With some professional terms	Simple plain language
	Verification	By stroke specialists in first-tier hospitals	By village doctors and township physicians
	Health behavior change theory	Health belief model and the transtheoretical model (stage of change)	Health belief model and the transtheoretical model (stage of change)
Message recording
	Speed	Normal speaking speed	Slower than the normal speaking speed
	Repeating	No repetition	Repeated once
	Dialect	Local dialect	Local dialect
Message dispatch algorithms
	Text message	3 pm every 2 days	No text message
	Voice message	7 pm every 2 days	7 am every day
	Receiver	Patients and caregivers	Patients only
Senders		Random phone number	Single consistent phone number