Abstract
Determination of acid phosphatase activity in clinical laboratories in New York State was evaluated. After the target values were established by 12 reference laboratories, sets of test samples were mailed over a two-year period on three occasions to, respectively, 264, 242, and 239 laboratories. Their initial (1968) results revealed problems: definition of normal ranges, interchange of specimens, standardization and quality control, and a need for improved techniques. Almost 5% of laboratories interchanged the initial specimens. Unexpectedly, laboratories using the same method reported a two-fold or greater variation in their "normal range." Although there was some improvement after refresher training sessions, performance was more clearly improved a year later for five of the seven major methods used. Use of the Bessey—Lowry—Brock, Babson—Phillips, and Shinowara—Jones—Reinhart methods resulted in the lowest coefficients of variation.
Colorimetric determination of serum acid phosphatase activity using adenosine 3'-monophosphate as substrate
