Table 5:

Unconscious and conscious factors that may contribute to discordant reporting of medical history, and potential mitigating strategies.

Factors that may contribute to discordant reporting of medical history
Unconscious	Conscious
Medical complexity;[31, 32] discordant reporting may be more likely when Diagnostic criteria are complex Diagnoses are made without radiologic evaluation (e.g., MRI), procedures (e.g., colonoscopy) or surgical intervention Implications of diagnoses are unclear or perceived to be non-life threatening	Stigma or perceived negative connotations, which may be encountered when asking about Mental health disorders Sexual behaviors, practices, preferences Substance use disorders / addiction Transmissible infections (e.g., HIV, hepatitis, syphilis)
Use (or misuse) of medical terminology with less clear diagnostic implications or associations, [27, 33] including “Mini-stroke”, “TIA”, “small vessel disease” Impaired glucose tolerance, “pre-diabetes” Acute coronary syndrome, coronary artery disease, unstable angina	Unease / discomfort pertaining to topic of discussion; relevant when asking about Impulse control disorders Perceptual abnormalities (e.g., hallucinations) History of abuse or trauma Sexual history / function
Disorders associated with impaired awareness or insight (anosognosia), including Neurodegenerative dementing illnesses (e.g., Alzheimer disease) Disorders associated with disturbed consciousness (e.g., seizures, syncope) Sleep disorders (e.g., REM sleep behavior disorder)	Primary or secondary gain, which may be more common in individuals with Active medicolegal concerns / disputes Medication-seeking behaviors (e.g., narcotic, stimulant and dopaminergic medications) Somatic symptoms and related disorders (e.g., factitious disorder, malingering)
Misinterpretation of symptoms/signs by individuals or practitioners, as may be seen in individuals with Declines in memory (reported as “normal aging”) Restless legs (reported as neuropathy, insomnia) Pseudobulbar affect (reported as depression, mood swings)
Potential mitigating strategies
Take additional history from a reliable collateral source Use clarifying questions, screen for associated symptoms and signs Obtain supportive evidence (supplemental records, laboratory/radiology reports, objective testing)	Interview the participant in a private setting with reassurances regarding the confidentiality of information (and limits as appropriate) Explain the relevance of the question to clinical care or research Normalize responses (e.g., “Some patients with this disorder report erectile dysfunction. Is that an issue for you?”)

HIV = human immunodeficiency virus; REM = rapid eye movement; TIA = transient ischemic attack