Grip strength feigning is hard to detect: an exploratory study.

Detecting submaximal effort when testing grip strength is difficult. Research so far has focused on the discrimination between sincere and feigning healthy participants, whereas the clinically relevant distinction is between injured patients and feigning participants. The aim of our study was to compare rapid exchange grip and isometric grip strength testing in 41 participants feigning weakness with 39 patients with decreased hand function. Various parameters that describe grip strength were recorded and tested for differences between the groups. Only the maximum grip strength during rapid exchange grip was found to be significantly higher in feigning participants compared with patients, but this cannot be used for decision-making on an individual basis. We found no parameters that are useful for the detection of feigned weakness in an individual case.

LEVEL OF EVIDENCE: III.