—A review of our findings and those of Jiménez-Alonso et al discloses the following important points:
The methods used for measurement of GGT are not completely similar in the two studies. Our normal values of 12.8 ± 6.6 IU/L differ from those of 33.83 ± 4.76 IU/L in the study by Jimenez-Alonso et al.
The Statzyme GGTP employed in our studies is a kit used frequently in the United States that well separates normal values from those found in many conditions of hepatic injury (12.8 ± 6.6 v 32 ± 10 IU/L [P<.001]). Does the same range of separation occur with the method used by Jimenez-Alonso et al?
Using statistical methods, it seems that approximately 20% of the patients with thyrotoxicosis and 20% of the patients with hypothyroidism in the study of Jimenez-Alonso et al have GGT levels outside the mean ± 2SD of the control subjects. It