The amount of analysis performed in determining the validity of a property of a digital circuit is measured concurrent with performance of the analysis, and provided as an output when a truefalse answer cannot be provided e. A voltage scaler scales the output voltage of the power amplifier using a voltage scaling ratio. Dopant particles of alumina, silica, titanium dioxide or a black dye or pigment may be added to the pretreatment layer to reduce the gloss and reflectance of the pretreatment layer in a printing process. More particularly, the IGF status may be determined by measuring IGF-I levels andor IGFBP-3 levels.