TABLE 2.

Comparison of audiometric procedures for the app (Audimatch) and the audiometer (MA25 eIII D).

Feature	MA25 eIII D (AM)	Audimatch (app)
Type of tone	Pure tone	Pure tone
Duration of tone	2s	1s
Response method	Signal detection, only “yes” responses	Alternative forced choice, “yes” or “no”
Possibility of response straight after beginning of tone	yes	no
Duration of response window	2s	unlimited, but pop-up window stating < < Choose “no” if you are not sure > > after 3s
Pause after response	2 – 3,6 s (random interval)	0.7s
Familiarization (right ear)	1000 Hz, presentation until double confirmation of threshold	1000 Hz, presentation until double confirmation of threshold
Familiarization level	Start value: 40 dB Level decrease for correct response: 10 dB Level increase for wrong response: 5 dB	Start value: 40 dB Level decrease for correct response: 20 dB Level increase for wrong response: 10 dB
Criterion for hearing-threshold	2 confirmations out of 3 presentations of the same ascending threshold at each frequency (shortened ascending method according to DIN EN ISO 8253-1)	2 confirmations out of 3 presentations of the same ascending threshold at each frequency (shortened ascending method according to DIN EN ISO 8253-1)
Ascending and descending step size (according to Hughson-Westlake algorithm)	5 dB HL up, 10 dB HL down	5 dB HL up, 10 dB HL down
Default intensity when changing frequency	10 dB decrease	20 dB increase
Default intensity when changing ear	30 dB	Hearing threshold from 1000 Hz in the right ear
Frequency [Hz] order right and left ear	1000, 1500, 2000, 3000, 4000, 6000, 8000, 1000, 750, 500, 250, 125, (1000)	1000, 1500, 2000, 3000, 4000, 6000, 8000, 1000, 750, 500, 250, 125
Re-Test at 1000 Hz	Yes	no
Procedure if deviation in re-test >10 dB HL	If difference at 1000 Hz ≤ 5 dB HL, change ear. Otherwise retest all frequencies until difference ≤5 dB HL.	not applicable
Class of medical device	1	1
Audiometer class	4	4