 The same is true of side effects. Tonelli (2006) discusses a case where a patient who suffers from multiple sclerosis receives a treatment that does seem to alleviate her symptoms, but since she has started taking it, she has been plagued by severe episodes of depression. Clinical trial results indicate that the drug is effective in treating multiple sclerosis, and no adverse psychiatric effects have been reported. Her GP and her psychiatrist now debate whether to continue the treatment. There are various reasons why the clinical studies do not show evidence of mental health effects: the trial subjects weren’t properly screened for depression; adverse effects were found but not reported; the adverse effects were not statistically significant—but they may have been clinically significant for some subpopulations; the side effects only obtain in populations that differ from the trial populations.