Real ear measurement vs. in-situ audiometry

I had a discussion with my acoustician.
I wanted to have a real ear measurement and she said that the Signia 7x can do an Insitogram via software.

Are the 2 techniques compareable? Theoretically, the structure of the ear is also taken into account with the Insitogram via the hearing aids.

They are not. Only REM will assure that the prescribed gain will be getting to the ear drum. Some claim that that doesn’t make it better, but they are undoubtedly different. The Insitogram is basically a hearing test done through your hearing aids.

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Thank you.

I understand it this way: Typically, you do an audiogram and program your aids accordingly.
Here, the peculiarities of the ear canal are not taken into account, so that the necessary sound pressure does not reach the eardrum. So that + 3dB won’t result in an 3dB increase.
When you do an Insitogram it should be better because you do an audiogram over the aids. Because of this is should take the special anatomy into account?

Then why is there still a difference? Would like to understand and argue.

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I claim no expertise. My impression is that receivers are not calibrated so one has no idea how much gain they’re delivering. With REM, one has a calibrated measuring device establishing the amount of gain being delivered.

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Also, when REM is done, mic for that is I think 5mm from the eardrum or 7 or something small like that I forgot, there’s area in which some high frequency has to be in initial test so confirm they’re inserted at the right depth.

And it MEASURES what comes to the eardrum.

HA receivers are either 2 cm or so away (it’s said that from eardrum to opening of the canal is 3 cm), with that distance varying depending on the exact position/dome/mold, or they’re even behind the ear.

REM measurement is done via a air tube, but, all parameters are exact and known. And that’s objective measurement as it can get. Yes someone can argue that the results won’t be exactly the same even half an hour later, but we’re not talking about 5db difference, but 1-2 maybe. Maybe.

In situ audiometry, no matter how they call it, is still relying on you saying when you hear and when you don’t hear. Tests are done in 5db steps. That’s not objective measurement, just taking notes from your feedback.

Also, audiogram is tonal.

REM measurement used for verification of fitting and further fitting is using calibrated recorded speech which resembles indo-european languages. Recording what my fitter has has something ‘… shorosh…pyming the boss’ where first part sounds hungarian, then a bit chineese, then english and whatnot, also french-alike I’ve heard and german… mix

And it uses some of scientifically proven formulas for fitting (most common NAL-NL2, but there are few mores like NAL-NL1, DSL-5 and whatnot), and compares HA output with what you should get by those formulas. In 1 db steps across whole frequency range, and you get the target and current output curve, and then by adjusting handles for frequencies in your HA software, you try to move output curve as close to target curve as possible.

Hearing aids have mic outside, so only thing they can measure is feedback. Yes it does take properties of real ear with that. But that’s not fitting for your hearing loss, that’s adjusting the settings for the device that it doesn’t squeak on your specific ear.

But, I wouldn’t argue. I would leave. You’re not paying them to teach them how to do their job.

If your fitter doesn’t know the difference or benefits, then they have no clue how to do proper fitting that helps you hear better, and are just sellers with more or less interest to learn from experience, obviously less since they think that proprietary manufacturer formula is godsend.

I had an encounter once with one ‘specialist’ who told me that it’s her good will to even attempting to do some tweaks, they were told to just use auto setup from manufacturer and that it works best and that I should be deeply grateful for she trying to listen when I say that it’s rubbish and if she can improve it. I left. Facepalming. They were asking double the price I paid for the same device at the different place. Back then I didn’t know about REM fitting, but that second place at least spend dozens of hours trying to fit it and working with me through my feedback and notes. But we went so much off from the initial setup that we didn’t use anything from manufacturer’s tools anymore.
If I knew about REM, I’d definitely look for it, but I doubt I could find it in that country, still people can’t find someone who does that.

On same device few years later different person tried to be smart. Used manufacturer stuff, tried to tweak a bit, but had no clue. I asked him to return my previous setting and left.

Leaving is an option.
And even if you paid, sometimes it can be better to leave than to die in frustration with poor fitter :confused:

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It’s probably like the Widex sensogram so the aids will need setting up with the software to give the correct manufacturer set up that takes all the settings and aid type into consideration and gives very highly researched results for instant high level performance. With Widex the sensogram is performed through the aids into your ear and the aid type selected, vent size/mould type etc and the feedback calibration performed before this. The calculations then all come together to give a very accurate set up. As an example as a long term very happy Widex user, when a dispenser used REM my hearing really dropped off as this doesn’t then come together with all the other information on their software.

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From what I have seen in the past, the people who rely on the built in test are mostly one of three things:
They drank the manufacturer’s “kool aid” believe it is accurate
Are too cheap to buy the right equipment
Are too lazy to the take time to run the proper test
I don’t mean to sound so nasty, but when all of the professional groups agree the “Best Practices” includes Real Ear or Speech Mapping, there is no good excuse not to do it.

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I’d also add ‘they need to look like they’re doing something for many hours in order to bill you those huge prices’.

But you what’s funny? Manufacturers themselves are teaching people to use REM equipment. I’ve seem phonak’s course on audiology online that reminds people about REMs and points where in sw they can plug that in.

But I was ‘educated’ this year by one fitter that such stuff isn’t useful, that it’s obsolete and he didn’t even feel that we should do any other tests (I asked for wrs) since I’m not native German.

Second fitter with whom I stayed said not doing tests is rubbish, I repeat what I hear, and he will know if I heard some phoneme or not, and we’ll just consider some good enough (if I say u instead of ü for example). Plus, I live here, it definitely makes sense to adjust my aida so that I understand German well :rofl:

But as long as we customers pay to those lazy ones, they won’t get the incentive to change.

I believe you are referring to the professional trade. Totally agree with you.

As a self programmer I do not have the tools to do REM. In the past I just didn’t have the money or insurance to get aids from the professional.

In-Situ programming has proven to me to be very good but I do understand how REM could be best, especially for a fitter who wants to get the fit close the first time. I have been told that most self programmers tend to under fit their aids. Knowing this I have pushed gains for better speech understanding.

Fitting aids with REM compared to In-Situ each have their advantages. Both can be done with great results with patients.

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Practitioners and manufacturers sometimes talk about future capabilities of hearing aids doing their own REM, but in my mind it still misses one of the biggest points: independent confirmation by a neutral device. If a hearing aid is doing its own REM, you have to trust that the device is doing what the manufacturer tells you it is doing, and they can tell you whatever they please. It has already been well documented that different manufacturers devices differ wildly when “set” to the same targets.

I agree with Blacky: If a practitioner tells you that an insitugram is the same as REM, this is just an indication that they have no idea what REM is or what its purpose is. OR, they do know and they are lying to you, which seems worse.

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An in situ audiogram is fairly accurate.

The test chain includes the chip, the speaker, the ear canal and YOU i.e. your ears and brain … using the EXACT configuration that you will be wearing. The only thing not checked is the microphones.

In contrast, a REM checks that the sound level near the eardrum matches that predicted by NAL or a similar algorithm. The algorithm creates values based on theory and population averages … YOUR ears and brain are NOT involved at any point. So a REM test checks the chip, the speaker, the ear canal and the mikes … but NOT you!

Visible Speech tests are simply a screen display showing the REM results in a pretty format. They are of no genuine use to the dispenser - but they are great marketing toys!

A REM test does have one use … it will reveal a broken hearing aid … but this is a rare event. I suppose it will also reveal a duff RIC receiver cable … but as I replace these at every annual service that is of no real use to me at least.

So … an in-situ test involves YOU in the process whilst a REM simply checks the sound levels against an Australian algorithm based on averages and not on you.

FWIW I have discussed REMS with British NHS audiologists. They hate them but have to do them as they are mandated. After the REM they have to retune the aids by hands as the REM recommended settings are rarely correct.

Essentially REMs are Verification tests … these check that the system is working as specified … even if that specification is wrong.

In-situ tests are Validation tests … they check that the system is what the customer actually wanted.

There are rarely Silver Bullets in any field in this world … and REMs are certainly far from being Silver Bullets.

In-situ tests aren’t perfect either - BUT - they include the customer’s perception rather than simply imposing a technician’s view on the customer.

Don’t drink the REM Kool Aid … at least check out the technical background before accepting any sales yarn.

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You’re wrong - for claiming that REM based fitting doesn’t bring anything over in situ audiogram. They’re completely different things.

In situ audiogram is only an audiogram, pure tones. I agree that it’s fairly accurate, but it’s purpose is only measuring pure tones.

You might hear those tones after HA is ‘fitted’ but still don’t have speech comprehension.

REM done fitting is using recorded and calibrated speech to ensure that you get what you’re supposed to get. And it takes acoustic of YOUR ear canal.

Yes, using NAL and similar formulas, since they’re scientifically proven to work for many people and are focused on speech comprehension as opposed to manufacturer formulas which only care about HAs not being immediately returned.

Yes patients might prefer some tweaking, but you’ll still stay in the ballpark of that curve, since it’ll give the best speech clarity.

And saying how in situ audiogram is validation what client want is ridiculous - I bet no one of us here wants to be able to hear only those 10 pure tones. We want to comprehend speech.

And REM fitted aids don’t impose anything - you do WRS and quick sin after them and client goes out happy to get the most possible of their aids.

Sales yarn sell all those who stick to manufactures formulas, who don’t do REM speech based fitting, who don’t do WRS and quicksin before as setting expectations, don’t explain those expectations to the client, and after fitting don’t check if they hit the expected.

REM is also in situ btw. :stuck_out_tongue:

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This is clearly a religious argument.

Many manufacturer’s formulae are modified NAL which they obtain under licence.
Also, some years ago I met an ex-NAL employee … all their work is theoretical … at that time the Australian institute did NOT have physical hearing aids to work with … they relied on manufacturers to tidy up their models!

Also, your suggestion that manufacturers only want to minimize returns is clearly nonsense & insulting - their researchers want to help the hard of hearing.

We are also talking about REM … not extra tests like SPIN. Those tests can be applied with in-situ testing too.

Anyway, you (and many others) have too much invested in your ‘REM is the Holy Grail’ position so it’s pointless arguing further.

BTW I am a Physicist & Chartered Engineer with 16 years of professional dispenser experience working with 1000+ people with hearing loss. What are your qualifications in this arena?

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I’m kind of agnostic on this debate. I think REM has value but I think I’d be arrogant to insist that it’s the only way to get a good fitting. I do think a lot of fitters/audiologists try to BS their way out of doing it. It’s my impression that most (at least the ones I’ve seen) audiologists focus on getting a fit that their patient likes rather than meeting any kind of objective standard. I think this often leads to underfitting. My comments are based on seeing 4 different audiologists. The universal approach seemed to be run first fit and let them know if you have any problems. I’ve also seen 4 different hearing aid fitters (3 from Costco) The Costco ones clearly had REM as a quality standard they had to meet. They also did the most thorough audiograms. The other hearing aid fitter was not able to do REM.

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Well, I have REM kit - but I always use in-situ.

Essentially human beings are just random lumps of meat - they are NOT predictable machines.

I have seen clients with IDENTICAL audiograms - and yet they have needed VERY different fittings.
How do NAL and DSL … or REM … deal with that?

At the end of the day we use SOME/ANY fairly rough technique to approach the settings the client REALLY needs … and then we use our fine tuning skills/experience to get the ‘correct’ fitting.

Sadly newly qualified dispensers - and others - don’t realize all this - and so put huge amounts of faith into the SCIENTIFIC approach … often without much luck.

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I’m HA customer who has ‘experience’ with several like you (of several hundreds and thousands of customers), and they just wasted my time in endless ‘tweaks’ which didn’t have any useful outcome, or they just messed up everything without any clue how to make it better. With last one of those I heard better without HA than with ‘his fitting’. And he even said to me that my loss isn’t rare at all and he fitted hundred of people with such loss. In his imagination, maybe.

Then I went to the young guy who does REM based fitting. First fit was miles better than ANYTHING I’ve ever received, and I went to 5 in one country (different companies) and 1 on another country.
Then since I have special snowflake of a loss, we worked together and tried few more ideas, end result being that I hear best with open fit and NAL-NL1, which definitely wasn’t what he expected I should use. But, I do have reverse slope loss. And it took him 3 different approaches to give me the best possible outcome.
Not several months of endless tweaking.

And experience of many many forum users confirms the same - many are just sellers and have no clue what to do with the sound.

My best previous experience was with a technician who is sound engineer in free time, but it took time, and a ton of guesswork. When I say time, I mean 1-2 time a week, like two months in a row, and each time at least 1.5-2h. He didn’t use REM. I doubt he even knew about it though. His colleague who is ‘speech therapist’ was utterly clueless.

Should I say that all those ‘experts’ pushed for closed mold and increasing bass, and everyone started with manufacturer suggestions, one even said to me that any tweaking she does is out of her goodwill, that she’s supposed to just give me what manufacturer said.

Sad truth is that even then I knew more about fitting than many of them back then, and today I could eat them for breakfast if I put my hands on aurical REM equpiment. Yes, for most patients it really is that simple. Hell, even for me wasn’t that hard.

Sadly, many of those fitters refuse to use their brain or even listen for feedback, they just repeat what manufacturers say to them.

So yeah, I don’t care about ‘amount of years of being paid for something’, I care for results, and REM based fitting on speech delivers.
If I could learn so much in several months, then people who are paid by me should definitely be on the top of the latest research!

Also, I hope I don’t need to dig on links to explain how there’s ton of REM measurements, not just one.

I’ll just leave this quote here, it sums up nicely what I also think:

I hate being lied to. And yes, one guy (the one where I could hear better without the aid, and I can’t understand my SO sitting on the bed with me with that ear) tried to sell me the same story you’re doing now - how audiogram by HA and manufacturer is all that’s needed, how REM is old and obsolete and doesn’t make sense etc.
Yeah. I saw his ‘expertise’.

:rofl:

Yeah, that’s why their new and revolutionary this season is just a bit tweaked item of previous season?
That’s why proper bug fixes aren’t done before release.
That’s why HAs cost insane amounts?
All for us? :rofl:

Manufacturers are doing things for profit and are seizing the opportunity. What drives them to be better than competition isn’t altruism but getting the market share.
And they don’t want to be too good, since they aren’t that innovative, so they wouldn’t have ace up in the sleeves for next round.

I appreciate some work they do, but I’ll be the first one to criticize what what they’ve done, let’s start with my favorite - phonak, and their ‘we test in production’ :rofl:
Not to mention horrible UX and lags.

And I definitely am eager to see how it will start to change now that apple released ability that earbuds become assistive listening devices.

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Not really. With REM you know what is happening at the eardrum, without it you don’t. Fairly straight-forward.

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I think it’s the only way to get good fitting FAST. And really good fitting.

Unfortunately, with many fitter you might spend years and not get good fitting because they have no clue what they’re doing.
If you’re extremely lucky you might find the one that will spend dozen of hours in tweaking to get you in right ballpark.

And I definitely agree, people are underfitted, because they don’t know what they should hear, and they aim for comfort and then leave HAs in the drawer since they’re not useful.

I think I’ve read somewhere that even today amount of HAs in drawers is like 30% or more? Or it’s the other way around.
I didn’t remember, it was just insane. Why to pay such high prices, spend so much time and not getting anything useful?

REM based fitting is done for kids, and babies, to ensure they develop proper speech.
And they do.

Insisting that ‘how to you hear me now’ method is better than REM is is just ridiculous.

REM won’t give you 100% hit, but tweaking from there to nice sound and still having comprehension is extremely fast, as compared to going from ‘sounds nice’ to ‘be useful’.

I’d argue that REM fitting is idiot proof, and you don’t need to be sound expert to make it decent, while you need to be a wizard to get something really useful starting from different approach.
And there’s not much wizards out there.

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@TrueBrit i am curious how many years have you been wearing hearing aids?

This really has nothing to do with a fitters ability to fit aids properly.

The argument between REM and In-Situ will go on for a long time. The flaw with both of them is they are both based on an averaged fits.

The fitting formulas are averages and we all know each of us are not average. This average will fit most but not all. This is where the above average fitter comes into play. A good fitter is the key to fitting aids well.

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