Avalanche transceiver search times during avalanche companion rescue - A prospective randomized single-blinded...

The aim of this study was to analyse the influence of voice navigation in a new generation of transceivers on the time and success rate of transceiver search in a simulated avalanche rescue scenario.

Fifty participants performed two randomized test runs, using two different transmitters with and without voice navigation. Primary outcome was success rate, total transceiver search and total location time, secondary outcome parameters comprised predefined time intervals (coarse search time, fine search time, probing time) and deviations from the recommended standard search procedure.

The study shows comparable results in success rate, total transceiver search time (111.1 s ± SD84.3 s) and total location time (134.4 s ± SD 112.6 s) for trials with and without voice navigation. Wrong initial search direction was corrected earlier in trials with voice (49.6 ± 6.9 s versus 93.7 ± 18.4 s p = 0.011). Participants were significantly faster in the second search trial (first 203.0 s versus 143.2 s; p = 0.002), a learning effect, more pronounced with voice navigation (voice 119.8 s vs. no-voice 164.8 s; p = 0.014). Deviations from the recommended standard search procedure were common (55 % of trials), without any difference between voice and no-voice navigation.

This study demonstrated a wide inter-individual variation in total transceiver search times and total location time in participants without experience. Voice navigation did not result in a significant reduction of transceiver search times but led to a faster correction of a wrong initial search direction and improved the learning effect significantly in second trials. Voice navigation could possibly optimize performance in participants without prior experience in stressful situations.