ACCEPTED LETTER In response to ‘Investigating hypothyroidism’ Different thyroid assays may greatly affect diagnosis and management of hypothyroidism Authors Tejas Kalaria 1 , Anna Sanders 2 , Jonathan Fenn 1 , Harit N Buch 3 , Clare Ford 1 , Helen L Ashby 2 , Pervaz Mohammed 2 , Rousseau Gama 1 4 Affiliations 1 Clinical Biochemistry, New Cross Hospital, Black Country Pathology Services, Royal Wolverhampton NHS Trust, Wolverhampton, UK. 2 Clinical Biochemistry, Russells Hall Hospital, Black Country Pathology Services, Royal Wolverhampton NHS Trust, Dudley, UK. 3 Endocrinology, New Cross Hospital, Royal Wolverhampton NHS Trust, Wolverhampton, UK. 4 School of Medicine and Clinical Practice, University of Wolverhampton, Wolverhampton, UK. Corresponding author: Tejas Kalaria Address: Blood Sciences, Royal Wolverhampton NHS Trust, Wolverhampton, UK, WV10 0QP Email: tejaskumar.kalaria@nhs.net Declaration of conflicting interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The authors received no financial support for the authorship and/or publication of this article. Ethical approval: Institution approved service evaluation project ID 5441 with the Royal Wolverhampton NHS Trust. Patient and Public Involvement: Patients or the public were not involved in the design, or conduct, or reporting of this work. Dissemination to patients not applicable. Contributorship: Acknowledgement: Data availability: Data available from the corresponding author on request.