Researchers studied 257 Mayo Clinic employees who frequently typed on the job. The percentage that actually tested positive for carpal tunnel was similar to estimates for the general public, according to the study.

Thirty percent of the typists studied reported some numbness in their hands. Of that group, 27 percent met medical criteria for carpal tunnel, based on a questionnaire and indications of where their symptoms occurred.

Nerve conduction tests on these workers showed that 3.5 percent of them had carpal tunnel syndrome -- a percentage similar to what would be found in the general population.

Researchers cautioned against making too much of one study, saying more studies involving larger groups of people should be done before concluding that typing doesn't cause carpal tunnel problems for workers.

Studies have shown that carpal tunnel syndrome is most of 10 caused by the repetitive motions of industrial workers -- not office workers -- according to the Mayo Clinic researchers.