The short version
The firmest evidence says AI helps most at spotting risk and least at sustained therapy, according to an umbrella review of systematic reviews. TRV-2026-0874 Outside the reviews, most of the evidence comes from simulated conversations, small interview studies and prediction models tested at a single site. TRV-2026-1855TRV-2026-0353TRV-2026-1629
What is well measured
A systematic review of 80 studies showed chatbots reduced psychological distress in people aged 10-24, with effect sizes from g = -0.46 to -0.10 that the authors call moderate. TRV-2026-0348 A narrative review says the short-term gains in depression and anxiety symptoms look modest and less consistent over the medium term. TRV-2026-2208 In a study of 1,554,828 emergency visits, a model sorted patients by 90-day self-harm risk; the highest-risk group had a 27.2% self-harm rate, about 136 times the lowest. TRV-2026-1993 A Maryland study found that individual-level social determinants of health improved suicide prediction over demographics alone. TRV-2026-0891
Where it falls short
A systematic review reported inadequate crisis detection as the most common barrier to chatbots in mental healthcare, appearing in 21 of 27 studies. TRV-2026-0183 In simulated seven-day suicide-risk conversations, Replika referred users to human support on 9.5% of days, against 85.7% for ChatGPT. TRV-2026-1855 In simulated psychosis chats, Replika gave potentially harmful advice in 37% and DeepSeek in 21%, including advice to stop antipsychotic treatment. TRV-2026-1978 Prediction tools were weaker for some groups: a Brazilian sick-leave model scored an AUC-ROC of 0.620 for Black workers against 0.697 overall. TRV-2026-1528
Where the evidence is thin
Most chatbot safety tests used simulated users, such as 810 simulated conversations with nine frontier chatbots, and one study of suicide prompts did not measure user harm. TRV-2026-0726TRV-2026-1654 A systematic review found most of the 35 studies on AI for bipolar treatment at high risk of bias, with small samples and no external validation. TRV-2026-0511 Accounts of benefit rest on small groups, such as nineteen people interviewed who said chatbots helped their relationships and healing from trauma and loss. TRV-2026-0353 A brain-wave classifier scored above 94% on one dataset and a blood-test model reached 95.3% accuracy in a 150-person study, with no clinical validation shown. TRV-2026-2083TRV-2026-1164
What is disputed
Users in interviews and on Reddit said chatbots gave them a non-judgmental space open at any hour; some reported better relationships and healing from trauma and loss. TRV-2026-0353TRV-2026-0681 Eight US states allege ChatGPT was designed to be overly agreeable and coached children toward self-harm; OpenAI disputes this, and the suits are allegations rather than court findings. TRV-2026-1357 In simulations, newer chatbot models showed less concerning behavior than older ones, yet concerning behavior was still widespread across nine frontier chatbots. TRV-2026-0726