Since neurotransmitter diseases are ultra orphan disorders, the diagnostic odyssey is markedly longer than for more common rare diseases. To elucidate the diagnostic odyssey, the authors, consisting of patient advocates and experts, designed questionnaires with the aim to evaluate the challenges of proper diagnosis and to identify the areas in need of improvement. Two questionnaires were designed, one for caregivers and one for health care professionals (HCP). The key questions aimed to …