Thyroid hormone is a master regulator of growth and development in all vertebrates. Thus, disruption of its synthesis and activity can lead to profound consequences. Past decade studies on thyroid function tests have established an efficient guideline for monitoring thyroid diseases, yet a significant proportion of healthcare providers do not defer to it in their practice. The aim of this study is to assess provider practices in the diagnosis and treatment of primary hypothyroidism due to autoimmunity at Boston Children's Hospital (CHB) for a primarily pediatric patient population. Commonly known as Hashimoto's thyroiditis (HT), this is the most common thyroid disease in the world as well as the most common manifestation of human autoimmune endocrine disease. Through CHB's bioinformatics institute, a rich data set was collected to assess the manner in which healthcare providers utilized relevant thyroid function tests (TFTs). This work assessed and confirmed the superior sensitivity of thyroid peroxidase autoantibodies (TPO) relative to thyroglobulin antibodies (TgAb) for diagnosing HT in children. We also verified proper utilization of thyroid stimulating hormone tests to monitor HT but concluded that there is a low utilization efficiency with regards to measurements of thyroid hormones (thyroxine and triiodothyronine). Based upon the observation of unnecessary monetary loss caused by improper TFTs utilization, it can be concluded that reflex testing at CHB may improve provider practices' efficiency for HT monitoring.