IMPROVED DETECTION OF SUBMAXIMUM EFFORT IN UPPER EXTREMITY STRENGTH AND STRENGTH-ENDURANCE PERFORMANCE TESTING

This study was a continuation of 2 investigations into methods used to help discriminate between maximum and submaximum effort in maximal po wer grip (strength), and repeated maximal power grip (strength-enduran ce). The purpose was to identify valid discriminator variables, which in combination would improve the detection of submaximum effort over s ingle discriminator variables. Three discriminator variables were iden tified for power grip strength, and also for power grip strength-endur ance, A criterion test was developed where the criterion for intention al submaximum effort was greater than or equal to two positive discrim inator variables and the criterion for a maximum effort was less than or equal to one positive discriminator variable in both power grip str ength and strength-endurance. The criterion test correctly identified 100% of healthy control workers (n = 26) applying maximum effort in po wer grip strength and strength-endurance; and correctly identified a t otal of 20 out of 24 (83.3%) submaximum tests for workers purposefully restricting their performances. The criterion test was also applied a cross the power grip data for a retrospective sample of 51 Workers Com pensation patients with unilateral upper extremity injuries, classifyi ng 17 patients (33.3%) as submaximal when using their unaffected limbs . Combinations of multiple discriminator variables were found to impro ve detection rates for submaximum effort when compared to using single discriminator variables.