The 27 hour monitoring by ULTRADIAN takes into account the rhythm of hormones throughout the day. It is hoped that this information may in the future improve and simplify diagnostic procedures. Follow-up of patients in endocrinology still remains difficult including clinical signs of over and under-treatment, questionnaires of quality of life and blood testing necessitating often retesting. Simplification of the diagnostic procedure by obtaining detailed knowledge about the rhythm of hormones may contribute to the improvement and individualization of treatment and may decrease morbidity and mortality of endocrine patients.