North Star Ambulatory Assessment is an ambulatory assessment developed specifically for Duchenne Muscular Dystrophy.

The North Star Ambulatory Assessment (NSAA) is a functional scale specifically designed for ambulant boys with DMD. The instrument contains clear and detailed instructions, with item scores varying according to a simple three point criteria, which should allow accurate reproduction by different groups. The scale has also the advantage to be quick to perform and to be suitable for application in young children. The NSAA also includes two timed items, run/walk for 10 meters and rise from the floor. While those times do not influence the score, they can be used to monitor changes over time. Although it was developed to assess ambulatory patients, the NSAA has been widely accepted and used to evaluate ambulatory motor performance in children and young adults with DMD, as well as in patients with other neuromuscular diseases.

MFM, which was valid and reliable in Neuromuscular Diseases, was used for gross motor function assessment. The items in MFM, which evaluate functions in 3 different sections (D1, standing position and transfers; D2, axial and proximal motor function; D3, distal motor function) in 32 items in total, are scored between 0-3. 0; cannot initiate any movement and maintain the starting position, 1; partially completes the exercise, 2; performs the exercise slowly and visibly clumsily, with compensations, 3; performs the exercise in the specified standard pattern. High scores indicate higher motor function and the result is expressed as a percentage of the maximum possible score to enable comparison with other scores