Assessment of the external quality control for urinary iodine in Xinjiang in 2007

The study assessed the proficiency of local (state and municipal) urinary iodine laboratories to conduct consecutive determination and the performance of the external quality control network in Xinjiang. Z scores were used for the evaluation process. With feedback results from 14 out of 16 participating urinary iodine laboratories, it was determined that 11 laboratories were qualified through the examination.