“…Eleven of the studies had controls ( 27 , 29 , 30 , 32 – 35 , 37 , 38 , 41 , 42 ), while five of them did not ( 27 , 28 , 31 , 39 , 40 ). Type of diabetes was specifically mentioned in six studies; four were T2DM ( 27 , 32 , 34 , 42 ), and two were both T1DM and T2DM ( 35 , 38 ). In terms of the type of vaccine; BNT162b2 was assessed in twelve of the studies ( 27 , 28 , 30 , 32 , 33 , 35 , 37 – 39 , 41 , 42 ), mRNA-1273 was assessed in two of the studies ( 32 , 35 ), CoronaVac, Sinopharm or SinoVac were assessed in four studies ( 28 , 29 , 31 , 39 ), ChAdOx1-S was assessed in four studies ( 32 , 34 , 35 , 40 ).…”