Reliability of testing measures in Duchenne or Becker muscular dystrophy

Area of Science:

• Neurology
• Physical Therapy
• Clinical Trials

Background:

• Duchenne and Becker muscular dystrophies are progressive genetic disorders affecting muscle strength.
• Reliable assessment measures are crucial for multi-institutional collaborative studies and clinical trials in these conditions.

Purpose of the Study:

• To determine the interevaluator and intraevaluator reliability of physical therapists performing specific assessment measures.
• To evaluate the reliability of manual muscle testing for function, range of motion, and strength in boys with muscular dystrophy.

Main Methods:

• Six physical therapists assessed 36 boys with Duchenne or Becker muscular dystrophy.
• Evaluations included manual muscle testing for upper and lower extremity function, range of motion, and strength.
• Data were analyzed using intraclass correlation coefficients (ICCs).

Main Results:

• Interevaluator reliability was highest for average muscle strength (ICC=.90) and range of motion (ICC=.76).
• Intraevaluator reliability showed high consistency across measures, with ICCs ranging from .80 to 1.00.
• Upper extremity functional performance showed lower interevaluator reliability (ICC=.58).

Conclusions:

• The assessed measures demonstrate sufficient reliability for multi-institutional collaborative efforts in muscular dystrophy research.
• Standardized methods, evaluator training, and documented reliability are essential for designing powerful clinical trials.
• Reliable data collection supports the detection of disease progression rates in Duchenne and Becker muscular dystrophies.