Is it time to replace Fryette's Law with Bayes' Theorem?

ice age cats fighting
These conflicts will drive physical therapists' decisions and actions for the foreseeable future:

Qualitative vs. Quantitative

'Skilled physical therapy' can be dichotomized into two camps: the probabilistic camp that embraces evidence based medicine (EBM), future risk analysis, clinical prediction rules, estimates of effect sizes and other modern tools.

Here's an example...

The other camp is the movement impairment camp that believes the penultimate physical therapist skill set is verbal and tactile feedback (same as it was in 1992).

Here's an example:
"Quadriceps strengthening into last 20 degrees of extension with mild manual resistance and proprioceptive cueing, 30 reps to fatigue, continues to decrease current extension lag and improve quality and duration of gait"
This division can be summed up as a 'qualitative' vs. 'quantitative' skill set - the old way was exclusively the former while the future is increasingly the latter.

Top Down vs. Bottom Up

Even in physician circles there in not universal accord on standards like clinical prediction 'rules': only 40% of Emergency Room student doctors use clinical prediction rules; only 60% of Emergency Room resident doctors use them.

The doctors cite 'complexity' as the reason why they don't use the 'rules'. Some therapists advise using simple clinical templates to avoid 'stifling' complexity.

You can get some of my simple (free) EBM physical therapy (paper) templates here.

This lackluster support has motivated some authors to call for a 'top down' mandate on the use of 'rules' for clinical decision making.

Many physical therapists in this listserve resist 'rules' that they believe infringe on their autonomy.

Many of us learned about evidence based medicine from a benign, 'bottom up' perspective:
  1. form a relevant clinical question
  2. identify your target patient sample/population
  3. search the literature
  4. consider your patient's values/goals
  5. apply the best available evidence in a judicious manner to your patient
Can a 'top down' model of evidence based medicine work with an autonomous physical therapist? Will clinician non-compliance force government and third party policymakers to mandate EBM standards for payment?

Private vs. Corporate

Is high volume + high quality physical therapy possible?

Many PTs believe 1-on-1 patient care for one hour is the epitome of 'quality'. We're taught in PT school that anything less is 'unethical'.

Many large, corporate clinics rely on low paying, commercial insurance (Aetna, United, BCBS/Anthem California, etc.) to achieve high volume and high revenue.

What about the ethics of outcomes? Should the patient get to choose? What if PT#1 get great results (outcomes + patient satisfaction) treating 4 patients per hour while PT#2 gets lackluster results 1-on-1?

Have some, select PT managers solved the high volume + high quality equation?

Until we reach an 'outcomes-based healthcare system' this is a rhetorical question. Some relevant bellwethers may illustrate my point:
  1. Spanish Physical Therapists - 100% of private practice PT in Spain is cash-pay. No Spanish Medicare payments go to small PT clinics - only to large, often hospital-based, PT clinics. Small practices refuse to accept Medicare due to the low reimbursement. This is true for Spanish private practice physicians as well.

  2. USPh - record net revenue in 2009 of $201 million due mainly to increased patient visits and $102.85 per visit collections. How do they do it? Does it matter? As long as the patient gets measurably better and is satisfied with their care.

  3. MD PT Partners - this firm takes a percentage, in perpetuity, for setting up a high-volume patient pipeline that aligns the financial incentives of the physician and the physical therapist. It's probably not illegal. Is this wrong? Only outcomes will tell the full story.
Government Process vs. Personal Process

Medicare process measures include the following:
  1. the 8-minute rule
  2. the -kx modifier
  3. 'skilled therapy' (as determined by an 'expert' auditor)
  4. time-in & time-out
  5. PTA supervision requirements based on treatment setting
  6. Minimal Documentation Requirements
  7. 'one-on-one' codes
  8. physician certification of the physical therapy plan of care
  9. et al
Personal process measures are demonstrated by the physical therapist who says...
"I can only see one patient per hour..."
Quality needs to be primarily determined by the patient (the customer) and the outcome - not primarily by process.

Mechanistic vs. Probabilistic


Mechanistic models are good for students and generalists - most PTs are specialists. Many of the new evidence-based 'rules' go right to a prognosis and skip the diagnosis altogether.

Examples of biomechanical models that help students are...
  • "The disc is a jelly doughnut..."
  • The sacro-iliac joint 'locks' and 'unlocks'.
  • Fryette's 'Law' describes the behavior of diarthrotic joints undergoing therapist-directed mobilizing forces.
Most of us learned these models in PT school. I learned them in 1992.

Probabilistic thinking in medicine is often described by Bayes' Theorem - start with a probability (prevalence) and update it with an observation or test that confirms or rules out the diagnosis.

Physical therapists are being held to new standards - we are expected to make decisions like doctors.

Is it time to replace Fryette's Law with Bayes' Theorem?

Can physical therapists traditional decision making styles guide us through the conflicts that await us?
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Is it time to replace Fryette's Law with Bayes' Theorem?
Is it time to replace Fryette's Law with Bayes' Theorem?
Reviewed by Merlyn Rosell
Published :
Rating : 4.5