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CORRECTIONIn a Letter to the Editor by George W. Kukerin in the October 2002 issue, an

error appeared in the text on page 541. Beginning with the second sentence ofthe second paragraph on that page, the text should read as follows:

Brennan et al4 demonstrated that manipulative thrusts in the neigh-borhood of 900 N caused a posttreatment increase in Substance P,7

further postulating that manipulations of force less than thoseshown to cause elevated substance P levels could be used as asham manipulation.7 Developing true and sham manipulative pro-cedures for asthma based on these criteria is dangerous for thefollowing reasons: . . .

We apologize for the error and regret any confusion it may have caused.

572 Licht, Christensen, and Høilund-Carlsen Journal of Manipulative and Physiological TherapeuticsCarotid Artery Blood Flow November/December 2002