Du Mortier and Coninx are also very careful to state that MHUs should not be viewed as an evaluation tool.  MHUs do not provide assessments as to the state of health in an area, but are a treatment intervention ONLY. As evidenced by Mortier and Coninx, MHUs are useful tools for providing some basic preventative and (barring any other options) acute health care when access is otherwise unavailable.  It is important to reiterate that MHUs should be viewed as a last resort in providing medical services during conflict, not as a first option, which may often be the case when planning for interventions in conflict situations, due to their perceived flexibility.