Application of an exponential curve equation for calculation of serum creatine kinase activity.

A four-point scale for determination of serum creatine kinase activity is suggested and the application of an exponential curve equation is proposed for cases with this enzyme activity exceeding 177 I.U. The introduction of this modification permits the activity of creatine kinase to be determined in high-activity serum without diluting the serum before determination since this is a source of error in certain muscular diseases.