Interobserver reproducibility of thyroid fine-needle aspiration using the UK Royal College of Pathologists' classification system.

Am J Clin Pathol 2012;137:831-835 833 © American Society for Clinical Pathology The Author’s Reply I read with interest the comments by Arya and Agarwal who broadened the discussion of vitamin D testing into an international context and raised a number of important points. First, 25-hydroxyvitamin D testing is currently not accessible in many parts of the world owing to financial constraints or lack of infrastructure. In this regard, philanthropic and governmental aid efforts will be invaluable in providing access to testing. Second, 25-hydroxyvitamin D testing in resource-poor countries would logically focus on identification of severe vitamin D deficiency in communities to help target nutritional programs. In this context, accuracy and precision of assays for 25-hydroxyvitamin D may be less an issue than having inexpensive point-of-care assays that can perform in varying and often challenging environmental and transport conditions. Last, vitamin D testing will need to be done in careful conjunction with nutritional programs.