Appendix

Comparison of Nomogram to Computer Application

Characteristic	Computer	Nomogram
Hardware Requirements	Computer, specialized calculator, or smartphone	Any straightedge, pencil
Software Requirements	Application encapsulating the relevant relationships	Graphical representation of the relevant relationships
Infrastructure Requirements	Computing resources, perhaps Internet access; if smartphone, appropriate app	Ambient light
Energy Needs	Electrical outlet or batteries	Ambient light
Learning Curve	Knowing what to punch in, plus learning curve for software, hardware, and infrastructure	Knowing how to connect two points, and how to interpolate a point on a scale
Documentation	What documentation? Where?	Self-documenting
Tool Distribution	Likely Internet access	Single sheet of paper
Results Distribution	Need printer or Internet connection	Hand-carry or fax document
Cost	Variable	Cost of duplicating and transmitting a single page
Accuracy (decimal places)	As many as you want… if the software provides them	As many as you need… given the precision of the input
Speed: As fast as…	…your hardware	…you can draw a straight line
Sensitivity Analysis	Repeated data sets	Examination of graphic
Implicit Solution	Usually difficult or impossible	Automatic
Common Failure Mode	Punch in wrong numbers	Can’t find glasses
Need to Calculate	None	None
Third World Use	Problematic depending on computing accessibility	Works so long as pencil and paper are available
GIGO Susceptibility	High; May be hard to detect	Garbage In is clearly documented
Permanence	Need a printer	Creates a written record as part of usage pattern
Trust Factor	Did the programmer get it right?	Did the nomographer get it right?
Communication	Single number output	Graphical interactivity
Pizzazz Factor	High: Very modern	Low: Old-fashioned slide-rule-like technology