Topic: The topic of the study is very much relevant to the modern biochemistry and medicine since the mechanism and effect(s) of sub-clinical hypothyroidism are beginning to be unravelled with the modern tools at the hands of researchers. Language: The language of the paper is reasonably good with minor corrections required at few places. Introduction: The topic has been introduced very well. Methodology: The methods used are not of a higher standard. ELISA kits are used for most of the estimations, although CV of the kits have been quoted in the text, these are manufacturer values and not the laboratory values. It would have been good if authors had used RIA or chemiluminiscence assays for the estimations. Reference values used for separation of the subjects into sub-clinical and overt hypothyroid groups are kit values. If the authors had an age matched control group, the reference range derived from this groups could be more relevant to the population than the manufacturer's provided values. Units: FT4 data should be reported in SI units (nM/L or pM/L) rather than ng/dl. Results:At some points, the results appear to be over-analysed. The statistics presented in the tables should be simplified to make it more reader friendly rather than statistician friendly, e.g. there is not need to report 't' values, 'sum of squares', 'df', between groups' 'within groups', 'total' etc. in the table 2A. Table 2B can similarly be simplified by 1) replacinf '0', '1', and '2' with SH, OH and Controls in the table. The sdt. error could be omitted so that the table reports mean differences, 95%CI and p-values. Table 3: 't' values may be removed; tshcase, ft4case etc could be modified to TSH, FT4 and TBIL etc. Page 8, Line 44-52 are redundant (by definition of subclinical hypothyroidism). Grammatical corrections:- Page 11, L57 'stage of subclinical stage' Page 12, L8, 'was been found' Page 12, L28, 'was been found' L30, 'role of bilirubin as a protective role' References: Ref.No 12, 14 page numbers? Ref# 15, 2013(19) Ref#23 Gunduz M et al .- please check '2012;2012:109797'