Match functional measurement to the goals of therapy
The major problem with reporting function and severity modifiers as required by CMS to support payment for outpatient therapies is that it is meaningless unless anchored to the range of human functional ability. CMS assumes the severity modifiers reflect a patient’s percentage of functional impairment as determined by the clinician furnishing the therapy services. As clinicians we know being able to eat, dress, bathe, walk, toilet and comprehend are all basic functions required to get though the day. Being limited in any activity could be a considerable functional impairment. However, some activities are more important than others. Attempting to equate how impaired someone may be based upon any set of activities and referenced to someone else with a different set of activity limitations is an apples to oranges comparison.
In the world of functional activity measurement, there exists a plethora of instruments (none of which measure the exact same thing nor calculate a value in the same way) to describe functional impairment. In therapy, it may be easier to ask the patient how impaired he/she is on a scale of one to ten and get more meaningful information. Nevertheless, the future of healthcare and rehabilitation is predicated on the ability to demonstrate value and distinguish effective interventions from wasteful-less effective interventions. Value perceived will not be good enough when determining how much to pay for care provided. Value must be quantified and equated to dollars, and that brings us back to measurement.
If we agree the purpose of therapy is to optimize functional improvement and if we expect compensation for that, we must give more attention to this value-based purchasing stuff and get involved in the discussion of how to quantify and compare the value of change in functional ability.
How do you pick a measure to quantify functional limitation?
When picking a measure to quantify functional limitation, pick one with the sensitivity to show change in what you are treating the patient for, i.e. goals of care. Make certain it is a valid representation of those goals and make certain its measure is repeatable. These tests are readily available; just do not feel free to bend the rules of how the measure is applied.
Someone will ask, “How much do you charge to improve function?” “Ten dollars a visit” is not a good reply when they respond with “I’ll take six visits” and you know it will take anywhere from twelve to twenty to even come close to getting the patient back to optimal performance. Predicting the resource cost to achieve an outcome is something the industry has not been good at doing and has never been held accountable for delivering that outcome. Payors and CMS hope that mandating measurement along with payment will provide some evidence to help predict what an outcome will cost.
Measures that have a broad scope of activity ranges are more applicable where the goals of rehabilitation are life quality focused, measures with a narrow scope of activity may be more appropriate for use where function is limited to performing a specific task (walking) or a targeted deficit (balance). However, implying that impairment estimates using different measures translate equally across measurement instruments without a common reference is impossible.
In practice where time is money, performing long time consuming tests is a costly endeavor and clinicians will look for a shorter version of functional measurement regardless of how accurate or appropriate the result.
The logical compromise
The Activity Measure for Post-Acute Care (AM-PAC™) is a computer adaptive patient self-assessment of functional ability; it spans a wide range of activity applicable for a broad patient population. In doing so, its scoring translates to a broad range for the hierarchy of human functional ability and is an appropriate indicator for calculations of daily activity limitation for patients receiving rehabilitation. Shorter versions of the AM-PAC have been developed to target population specific or impairment specific areas of measure and require less time to complete. More importantly, scoring of the short versions of AM-PAC translate to the same scale as the computer version, which enables the correlation of targeted assessment (short form) scores to the broader range of function and limitation as the full AM-PAC.
When attempting to compare apples to apples for functional measurement, the short form approach is a logical compromise of time versus precision in estimating a patient’s functional limitation status. Policy makers and those paying for healthcare are beginning to understand the subtleties of impairment measurement. As care providers, we can help by utilizing measures appropriately when asked for the data.