Table 3.

Different AA vs. AP TTI measurements: A comparison of the literature. The symbol AP without specification was denoted when no further information on AP position was available.

Literature	AA/AL Placement	AP Placement	TTI in AA Position Mean(± SD) in Ω	Mean TTI in AP Position Mean (± SD) in Ω	n for AA	n for AP
[44]	AA1	AP	$73.8\pm 16.8$	$65.5\pm 14.5$	31	39
[45]	AA1	AP	$75.4\pm 13$	$66.7\pm 16$	23	57
[42]	AA1	AP1	$82.09\pm 24.6$	$71.29\pm 23.5$	20	20
[46]	AA3	AP5	$77\pm 18$	$72\pm 20$	17	17
[47]	AA	AP	$77.5\pm 18.4$	$73.7\pm 18.7$	45	45
[21]	AA1	AP4	$90\pm 21$	$85\pm 18$	150	157
[48]	AL	AP2	$107.2\pm 22.3$	$96.6\pm 19.2$	86	86
[30]	AA1	AP6	$92.6\pm 16.99$	$92.1\pm 23.3$	21	21
[30]	AA1	AP6	$75.8\pm 14.1$	$66.5\pm 13.9$	21	21
[36]	AL	AP	$81.4\pm 17.6$	$70.9\pm 16.6$	11	11