The interdependency of peak pressure and pressure–time integral in pressure studies on diabetic footwear: No need to report both parameters

The four different types of footwear tested in this study: (A) custom made therapeutic footwear, (B) a cast shoe, (C) a forefoot offloading shoe, and (D) a standard shoe.

Peak pressure–time curves shown in the left panes and scatter plots of maximum peak pressure (MPP) versus peak pressure–time integral (PTI) shown in the right panes for two foot regions in one subject: the midfoot and metatarsals 2–5. These figures clarify the two different criteria of congruence used for the individual analysis. The midfoot region shows a high correlation coefficient between MPP and PTI (r>0.7). The metatarsals 2–5 region shows a low correlation coefficient (r<0.7), but small coefficients of variation (CV<10%) for both parameters, indicating a high congruence of peak pressure–time curves from subsequent foot steps.