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How to interpret this comparison RIC vs BTE HAs?

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I brought my elderly relative to a public hospital for a "hearing aid benefit evaluation" comparing two pairs of hearing aids. Sound-field pure-tone and speech audiometry tests were performed while wearing the devices. From the beginning, I clearly stated to the hospital audiologist that I wanted to know the word recognition score () percentage at different intensity levels with both sets of hearing aids, in order to determine which pair provided better speech discrimination and at which sound levels.
The audiologist performed 3 sound-field tests; below are the results:

1) Unaided:

Sound-field Pure-Tone Audiometry: Threshold at 75 (Left Ear), 90 dB HL (Right Ear).

Sound-field Speech Audiometry: Speech discrimination capacity of 50% at 70 dB bilaterally.


2) With Unitron Moxi Blu B9-R with UP receivers in custom earmolds:
Sound-field Pure-Tone Audiometry: Threshold at 45 dB HL (Left Ear), 60 dB HL (Right Ear).
Sound-field Speech Audiometry: Speech discrimination capacity of 50% at 70 dB HL bilaterally.
SEE 2nd POST (I can't post more than 1 image per post).

3) With Phonak Naida Lumity UP L50 with custom silicone "koki" (full-concha) earmolds:
Sound-field Pure-Tone Audiometry: Threshold at 40 dB HL (Left Ear), 50 dB HL (Right Ear).
Sound-field Speech Audiometry: Speech discrimination capacity of 40% at 40 dB HL (Left Ear), 70% at 60 dB HL (Right Ear).
SEE 3rd POST (I can't post more than 1 image per post).

My questions:

a) The tests with the were conducted on one ear at a time, I mean not a single test was performed with the patient wearing both left and right hearing aids simultaneously. When I asked for clarification, the audiologist stated: "Analyzing one ear at a time yields a more precise result." However it's a fact that HAs are worn simultaneously in real life! What is the clinical utility of two separate monaural free-field scores? Furthermore, afaik modern HAs utilize wireless ear-to-ear (E2E) communication to constantly exchange acoustic data between the left and right devices, eg. if a signal originates from the right side, the right HA captures and amplifies it for the right ear, while simultaneously transmitting data to the left HA so that it can dynamically attenuate or shape the output on the left side.

b) Last March we had headphone speech and pure-tone audiometry performed at a different hospital and these were the results. That speech graph was easy to read, but I am struggling to interpret the speech audiometry graphs printed on these three new reports. Could someone explain how to properly read these speech diagrams?

c) How can we compare speech discrimination scores when the devices were tested at different presentation levels?
I mean:
Naída BTE: L = 40% @ 40 dB, R = 70% @ 60 dB
Unitron RIC: 50% @ 70 dB bilaterally
Is it guaranteed that testing the RICs at 60 dB would yield worse discrimination than at 70 dB or does speech recognition not strictly follow a linear pattern with sound intensity? I can't understand what methodology the audiologist followed here!

d) Comparing the unaided speech test (50% @ 70 dB) with the Unitron Moxi RIC test (50% @ 70 dB), there is zero difference at 70 dB, so this means wearing the Moxi RICs provides no measurable improvement at this level. Our hearing care professional who programmed them claims they were set to maximum volume (105 dB fitting range). How is this possible acoustically or clinically?

Based on these test results, can any audiologist or hearing care professional advise if (and to what extent) switching from RIC to BTE Ultra Power is beneficial in terms of speech understanding?

2) With Unitron Moxi Blu B9-R with UP receivers in custom earmolds:
Sound-field Pure-Tone Audiometry: Threshold at 45 (Left Ear), 60 dB HL (Right Ear).
Sound-field Speech Audiometry: Speech discrimination capacity of 50% at 70 dB bilaterally.

3) With Phonak Naida Lumity UP L50 with custom silicone "koki" (full-concha) earmolds:
Sound-field Pure-Tone Audiometry: Threshold at 40 (Left Ear), 50 dB HL (Right Ear).
Sound-field Speech Audiometry: Speech discrimination capacity of 40% at 40 dB (Left Ear), 70% at 60 dB HL (Right Ear).

Congratulations on being such a proactive advocate for your relative.

The audiologist in question was very accommodating in performing this additional testing at your request, but it doesn't seem like they perform this type of testing on a regular basis, or if they do they are not particularly good at doing it yet.

While unaided puretone soundfield are fine, aided testing shouldn't be performed using puretones because the hearing aid signal processing is optimized for speech and can suppress puretone signals resulting in inaccurate threshold measurements. Threshold-based testing should use speech-based stimuli, but if these aren't available the aids can be switched to verification mode and narrowband noise can be used as an alternative.

Aided testing can be performed monaurally and this isn't necessarily a bad idea where there are significant asymmetries between the ears, however a measurement should also be performed. The test levels chosen for aided testing should've included average level speech (e.g. 65dBSPL) and if performance wasn't above 80% a level higher than this to simulate loud speech (75dBPSL) to measure maximum performance. Soft speech should be tested if performance isn't below 50% for average level speech.

For someone with your relatives degree of hearing loss, it is often helpful to test not only isolated words when performing speech recognition testing, but also connected speech in the form of sentences as a lot of information can be be gleaned from context. This would give you a more better idea of what kind of performance might be expected in the real world.

RE: a) Don't worry about the e2e being affected by monaural testing in this case. The more important thing is that binaural speech input adds a lot of redundancy because two speech signals are reaching the brain and there is also binaural summation of the signal resulting in an increase in the loudness of the perceived signal. These are more important reasons for performing binaural aided testing in addition to monaural testing.

b) The audiologist hasn't performed testing at enough levels to provide an indication of as to how much better your relative will perform with increases loudness of speech, which is important for you as it informs how you might interact with them (raised voices, distance at which you can expected detection and understanding of speech). The only comparisons that can be made are between the and the UP devices, the latter showing better performance for this task.

c) The only comparison you can make is that your relative did better at softer levels with the UP devices. The levels tested don't allow for any other conclusions, such as how much better they might be doing.

d) Are the Moxi devices working properly? Have they been run through test box measures to prove they are performing as they should? This should've happened before new hearing aids were considered.

@Hearing_Potential said:

b) The audiologist hasn't performed testing at enough levels to provide an indication of as to how much better your relative will perform with increases loudness of speech

After reading your response, I feel so much more relieved because I thought I was simply incapable of interpreting the speech audiometry diagrams! So I was right to believe that the audiologist conducted the speech tests terribly, limiting them to just a few arbitrary levels. A direct dB -> % comparison between the two is practically impossible now!

Furthermore, before starting, I explicitly told him that I wasn't interested in pure-tone testing, only speech audiometry. I also mentioned that I wanted to evaluate the HAs as a "complete system" (I mean binaurally), with the patient wearing both HAs simultaneously and that I was fine with just testing speech with a single front speaker rather than running separate L/R tests so we could save time, given we had 2 sets of HAs... the audiologist snapped back: "You're doing everything yourself; do you want to run the test too?". Extremely rude and unprofessional and the reports I posted are proof of that!

@Hearing_Potential said:

d) Are the Moxi devices working properly? Have they been run through test box measures to prove they are performing as they should?

Right at the beginning, when I accompanied my relative into the sound booth, I immediately noticed both the Aurical test box (aka HIT) and the REM (Real Ear Measurement) system. I asked right away: "Can we run a test box evaluation?" and the audiologist replied: "No, that's used for other things, it's not needed in this case." I was speechless!

After all this, you've confirmed that it's impossible to gather sufficient data to properly compare these two HAs. This was the first time I brought my relative to this public hospital for this service and it was a terrible experience: a total waste of time for me and a huge source of stress for an elderly person.

Sorry for this rant!

The phrase "test box measures" encompasses a much broader range of measurements than Dr Cliff describes and in a hospital they'll also be used for simulating real ear measurements for young children which may be what your audiologist was thinking of. They should've asked more clarifying questions to figure out what you meant by this. I would ask them to do this the next time you see them. I think if you specifically asked for measurements of the aids to prove that the devices were performing to manufacturer specifications the audiologist would know what you meant. It seems as though they are trying to be accommodating and they shouldn't have a problem with this request given the poor aided performance measured with the Unitron aids.

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