It is an indirect way of assessing how difficult an intubation will be; this is more definitively scored using the Cormack–Lehane classification system, which describes what is actually seen using direct laryngoscopy during the intubation process itself.
This approach provides an indirect evaluation of intubation difficulty; however, a more precise assessment can be made using the Cormack–Lehane classification system, which visualizes exactly what is seen through direct laryngoscopy during the procedure.