Some types of disability are invisible. You can't see vertigo, nausea or a flu-like malaise just by looking at someone's face. Since the effects are often non-specific, correct diagnosis depends on being able to give an adequate description of one's symptoms, and on the condition being recognised by a knowledgeable practitioner. The following article describes my experiences after a bout of flu left me with chronic vertigo. It discusses the effects of misdiagnosis, and the prejudices which can influence clinical judgement.
Health professionals tend to equate disorders with a set range of impairment.
Thus condition A is associated with Y amount of disability while treatment B carries an expectation of Z amount of side-effects. As a psychologist, I know that AIB is a valid concept. The term covers the situation where patients misinterpret their symptoms, delay seeking advice or adopt maladaptive coping strategies. It describes irrational behaviour, or rather, what doctors regard as irrational. What is adaptive is also defined in medical terms.