The psychopathological model of mental retardation: theoretical and therapeutic considerations.

Smith et al. (1997) drew a new map. They call it the "universe line" model.

It lines up medical, mental-health, and social facts about people with intellectual disability.

The paper is only theory—no new data were collected.

The model shows how IQ, behavior, and mental illness can sit on one straight line.

The goal is to help teams see the whole person, not just the score.

Singh et al. (1991) had already said "use many tools"—history, checklists, short tests. G et al. kept that idea but added the single-line picture.

Dosen (2007) later added a fourth piece—developmental age—to the same bio-psycho-social frame. The model keeps growing, like stacking Lego bricks.

McGeown et al. (2013) shifted the spotlight from illness to daily functioning. Their update does not kill the 1997 line; it just moves the focus to what the person actually does.

van Timmeren et al. (2016) warned that most number-crunching studies in this area use weak stats. G et al. escaped that critique because they never ran numbers—yet any future test of the line must use better methods.

You now have a one-page sketch you can draw for parents and staff during intake. Draw the line, mark where the client sits, then add medical, behavioral, and social notes. It takes two minutes and shows why you need both a psychiatrist and a behavior plan.