Gary L. Kreps,Linda Maguire, Hidden Factors in Diagnosing Alzheimer’s Disease Neurology and Neurobiology 2020 2613-7828 http://dx.doi.org/10.31487/j.NNB.2020.01.06 https://www.sciencerepository.org/hidden-factors-in-diagnosing-alzheimer-s-disease_NNB-2020-1-106 Abstract: Diagnoses of Alzheimer’s, dementia and other mental health conditions using the “family history method” can often be inaccurate, biased and possibly ill-motivated. Definitive clinical testing and/or biological tests rarely exist for most mental illnesses. Even when tests (such as PET scans or excess Abeta42 in cerebral spinal fluid indicating presence of neuronal plaques, for example) and other suggestive biomarkers are "positive", there are often no outward cognitive-behavioural symptoms or symptomatic evidence associated with the alleged mental illness (and vice-versa). Furthermore, environmental stressors, dehydration and other fully curable illness and treatable issues such as urinary tract infections, delirium, drug interactions and insomnia can quickly create outward ‘false’ symptoms of mental illnesses, often mistaken for true mental health diagnoses. Therefore, a comprehensive consideration of ex parte narratives, experience, familiarity and also possible underlying motivations, of even the most well-meaning family members in the “family history method” of mental illness diagnoses, currently used by doctors and other professionals, should be revisited.Keywords: Mental illness diagnosis, dementia diagnosis, Alzheimer's diagnosis, proxy diagnosis, family history method