We're using G-codes as a stepping-stone to an outcomes-based reimbursement system, aren't we?" asked my client today. Jami is a nurse running a occupational theapy hand clinic. Jami is preparing her office for mandatory G-code reporting on July 1st, 2013.
"No", I replied. "We're just reporting our compliance. We're not measuring function."
"Well, we showing we're getting the patient better, aren't we?", replied Jani.
"No, not really", I replied. I paused in the conversation, not sure how I could quickly explain the statistical concepts needed to understand why Functional Reporting using G-codes and Severity Modifiers could not lead physical therapists to true outcomes reporting.
"What a bust for FOTO", I thought. Focus on Therapeutic Outcomes had the Cadillac risk-adjusted outcomes measurement system for therapy services in the world and the US government took a pass on them and chose G-codes and Severity Modifiers instead.
Of course, FOTO costs $250 for set-up and $25 per month per therapist. And, they own the outcomes marketplace. There is essentially no competition. I could just imagine the hue and cry if the government granted a de facto monopoly to FOTO and mandated that every therapist measure patient outcomes using a risk-adjusted measurement scale, like FOTO.
"We know how to measure outcomes!", Jami said, eagerly. "We're using the DASH already!"
"I use the DASH, too", I explained. "And, that's what Medicare wants. But, a discharge score on the DASH that is, say. 20-points better than the initial score can't be used to compare your clinic to mine."
There are four levels of measurement (adapted from Jewell):
|Level of Measurement||Example|
|Nominal||apple, orange, pear|
|Ordinal||happy/sad OR hot/warm/cold OR MMT grades|
|Interval||temperature, height, weight|
|Ratio||blood pressure, speed and distance|
There is not a fixed interval between values such as "happy" or "sad" or, for that matter, the rank ordered scales of the OPTIMAL, the DASH or any of the other paper questionnaires.
These rank orderings are not numbers but are indicators for modifying words. The OPTIMAL uses words for values such as 2 = "little difficulty".
The lack of a fixed interval between these values means that mathmatical functions cannot be performed on them. The difference between a "1" and a "2" is not the same as the difference between a "2" and a "3". We can't add, subtract, multiply or divide OPTIMAL, DASH or any of the other self-report scales becuse they lack intervals.
The interval level of measurement has a fixed interval between each number which allows addition and subtraction. A 10-point change in temperature from ninety degrees to eighty degrees is the same ten point change from fifty to forty degrees.
The ratio level of measurement has a known zero point which indicates the absence of the chacteristic being measured. Zero miles per hour means the car is standing still. Ratio data can be manipulated like interval data with addition and subtraction. Also, ratio data can be manipulated with multiplication and division.
All of these techniques are being used to convert self-report scale data from raw scores to the new Medicare Severity Modifier scale.
That is probably fine for simple reporting to prove to Medicare that physical therapists can report functional scores.
But, when Medicare starts paying one therapist more money for better outcomes based on functional data they had better create something better than G-codes and the Severity Modifiers.