Equation of Moore and Garb for Predicting the Incidence Rate of Distal Upper Extremity Disorders from Occupational Exposure

Distal upper extremity disorders includes carpal tunnel syndrome, DeQuervain's tenosynovitis, stenosing tenosynovitis in digits or other disorders of the fingers, hand, wrist and elbow.

Parameters:

(1) incidence rate as occurrences of distal upper extremity disorders per 100 workers per year

(2) intensity of exertion as percent of maximum strength

(3) recovery time as percent of cycle time

where:

• Both intensity of exertion and recovery time are percentages. The equation appears to use them as decimal fractions (percent divided by 100); using them as whole numbers results in unacceptable results.

• Wrist posture during the task is an independent risk factor but to a lesser extent.

incidence rate as percent =

= (30 * ((percent of maximum strength as decimal fraction)^2)) / ((percent recovery time as decimal fraction) ^ (0.6))