develop a common format scheme and value coding for InterventionIntensity

[mwvoss]

InterventionIntensity can currently take any value below. We should determine a common formatting scheme and common way of coding the values so that multiple studies can be grouped together. This may mean separating this variable into distinct variables.

"InterventionIntensity": [
"10-20beats increase",
"3Mets",
"40-50%MaxEffort",
"40-65%HrReserve",
"50-60%MaxExertion",
"50-60%V02Peak",
"55-65%V02Max",
"60%HrMax",
"60%V02Max",
"60%V02Peak",
"60-70%HrReserve",
"60-75%AgePredictedMax",
"60-75%HrReserve",
"60-80%HrReserve",
"60-85%HrReserve",
"65%MaximalAerobicPower",
"65-70%V02Max",
"65-75%HrMax",
"65-80%HrReserve",
"70%HRReserve",
"70%HrMax",
"70%V02Max",
"70-80%HRReserve",
"70-80%HrReserve",
"70-85%HrMax",
"70-85%HrReserve",
"75%HrMax",
"75%HrReserve",
"75-85%HRReserve",
"80%HrMax",
"80-85%HrMax",
"85%Aerobic-AnaerobicThreshold",
">3METs",
"LactateThreshold",
"Moderate",
"NA",
"PerceivedExertion-LightToModerate",
"PerceivedExertion-Moderate",
"PerceivedExertion-ModeratetoVigorous",
"PerceivedExertion-VeryLighttoModerate",
"VT1"
],