People who suffer a traumatic brain injury might not be thinking straight but still might have to make crucial medical decisions, a U.S. researcher said. Daniel Marson of the University of Alabama at Birmingham tested 86 traumatic brain injury patients\' ability to understand medical options, decide on treatments and appreciate consequences of their choices. One month after injury, patients with moderate or severe traumatic brain injury -- and some with mild traumatic brain injury -- still had impaired decision making skills. \"Even patients with mild injuries really depend to some degree on family members assisting them and guiding them, even if the patients still are able to make the decisions themselves,\" Marson said in a statement. The study was published in the journal Neurology.