Table 10.

Signal duration.

Description	Articles
<5 min (10)	[41, 66, 77, 98, 99, 111, 130, 146, 170, 175]
5–9 min (39)	[40, 80–82, 84, 85, 93, 101, 103, 115, 127, 134–136, 138, 141, 142, 145, 147–150, 152–160, 162, 163, 166, 169, 172, 176, 177, 179]
10–20 min (17)	[37, 86, 88, 89, 92, 109, 110, 120–124, 128, 131, 143, 164, 174]
>20 min (16)	[26, 38, 39, 91, 94, 107, 112–114, 119, 129, 137, 139, 144, 151, 178]
Not informed (30)	[42, 58, 78, 79, 83, 87, 90, 95–97, 100, 102, 104–106, 108, 116–118, 125, 126, 132, 133, 140, 161, 165, 167, 168, 171, 173]