Accuracy of Cryptorchidism Diagnoses and Corrective Surgical Treatment Registration in the Danish National Patient Registry

The data on cryptorchidism in the Danish National Patient Registry are quite accurate. In etiological research the limited misclassification will in most cases only slightly attenuate estimates of the true relative association. Thus, the registry has the potential to serve as a valuable research tool, although caution should be exercised when studying time trends or geographical differences.