Tozzi, A. A "nonlinear approach to pediatric diseases (electronic response to Hymel KP et al. Validation of a clinical prediction rule for pediatric abusive head trauma. Pediatrics. 2014 Dec;134(6):e1537-44. doi: 10.1542/peds.2014-1329).
To make an example,
we used unpublished data from a population of constipated children from Caivano, Italy, to build the graphic below with coordinates x (time) and y (divided into two zones: non-constipation and constipation). We obtained “trajectories”, i.e. vectors describing the illness of each subject in time. The trajectories of children who did not develop the disease followed a straight line parallel to x, while the affected children’s trajectories, “attracted” by the constipation zone, intersected the axis x at the age of onset of symptoms and entered the ceaseless orbit of the spiral. When a subject recovered, his trajectory left the orbit and went towards the non-constipation zone. If a subject did not recover, his trajectory persisted indefinitely in the constipation zone.