Table 3.

Reviews on previous studies on prevalence of hypothyroidism in diabetes mellitus.

First Author Year	Design, Sample size,  Country	Prevalence of Clinical Hypothyroidism	Risk factors Identified if any	Remarks
Al-Geffari et al, 2013 [12]	Retrospective, 411, Saudi Arabia	15.3%	F gender, duration of diabetes > 10 year	Nil
Diez, 2011. [13]	Cross Sectional, 318, Spain	3.5% ( overt hypothyroidism) 3.1 ( sub clinical)	Nil	No relation with duration of DM
Palma, 2013 [14]	Cross Sectional, 386, Brazil	0.7% (12.7 subclinical)	Nil	Nil
Demitrost, 2012 [15]	Retrospective, 202, Manipur, India	27.7	Age, BMI > 25	Nil
Kumar RA 2017 [16]	Retrospective, 400, Bangalore India	12%	Nil	Nil
Akbar, 2006 [17]	Case control, 100 diabetic patients with 100 controls, Saudi Arabia	16% (thyroid dysfunction)	Nil	Nil
Perros, 1995 [18]	Cross sectional, 1315	6.9% (Thyroid dysfunction in T2D)	Nil	Nil
Celani, 1994 [19]	Cross sectional, 290,	7.25%	Nil	Nil
Fleiner, 2016 [20]	Prospective, 1452, Norway		Nil	No significant relationship with T2DM