Ecological momentary assessment involves repeated sampling of patients' current behaviours and experiences in real time, in the patients' natural environments. The approach aims to minimize recall bias, maximize ecological validity, and allow study of microprocesses that influence behaviour in real-world contexts. aiMH lab studies assess particular events in patients' lives or assess patients at periodic intervals using smart phone and wearable technologies.  Joseph Hayes has developed a flexible ecological momentary assessment system called juli. juli is a chronic illness tracker, currently covering depression, bipolar disorder, chronic pain, headache, migraine, asthma and hypertension.