Table 2.

Details of the AI-powered chatbots intervention in the included studies.

Study	Theory or core element	AI Methods	Duration	Type	Input	Output	Dialogue management	Dialogue Initiative	Task-Oriented	Therapist involved	Comparison
Al-Hilli et al. [26]	Health education and counseling	NLP	Flexible	Chatbot	Written	Written	Frame based	System	No	Yes	Traditional counselling
Bibault et al. [27]	Health education	Machine learning	Flexible	Web based or smartphone application	Written	Written	Frame based	System	Yes	No	Physician
Echeazarra et al. [28]	Education	Not reported	Daily, for 2 years	Smartphone app, chatbot	Written	Written	Finite state	System	No	Yes	Traditional writing
Gong et al. [29]	Behaviour change theories	NLP	Weekly up to one year	Smartphone app, chatbot	Spoken, and written	Spoken, and written	Frame based	System	Yes	Yes	Usual care
Greer et al. [14]	Stress and coping theory	Not reported	4 weeks exposure	Facebook messenger; chatbot.	Written	Written, visual	Finite state	System	Yes	No	Waitlist control
Hauser-Ulrich et al. [30]	Cognitive behaviour therapy, psychological therapy	Not reported	Every day, for 8 weeks	Smartphone app; chatbot	Written	Written, visual	Finite state	System	No	No	Education
Hunt et al. [31]	Cognitive behaviour therapy	NLU	8 weeks	Smartphone app; chatbot	Written	Written	Frame based	System	No	No	Waiting list control
Tawfik et al. [32]	Self-care behaviour	NLP	Flexible	WhatsApp; chatbot	Written	Written	Frame based	System	No	Yes	Nurse-led education and routine care