We are developing a tele-care system for the management of hypertensive type 2 diabetes mellitus (T2DM) patients using spoken dialogue technology. This paper discusses the human factors which have been considered in the development and design of 'DI@L-log', with regard to the potential complexities posed by speech systems in the medical domain. To accomplish this goal, fine tuning of event handlers, error mitigation and the appropriateness of speech as an interface to chronic care are examined.