When real-ear measures were first developed, the researchers placed microphones into peoples ears. Placement of a physical microphone into the ear was a necessity at the time but is not the current or preferred method. Today’s measurements use a thin, acoustically transparent tube that essentially extends the microphone into the patients ear. These probe tubes are acoustically calibrated and do not introduce any changes to the measurement as suggested, the measurements are highly accurate.
Any concerns about the probe tube being squished are minimal and easily seen in the measurement. Most audiology students can accurately measure a real-ear response within the first day of training. It adds a nominal amount of time to the fitting process and provides information that is essential to every hearing aid fitting.
Sticking the aid in your ear (apart from the inherent cross-infection risk) isn’t going to be a good way to adjust it, as your hearing loss, canal volume, canal impedance and loudness growth experience will differ from those of the patient.
Now, I suggest you edit that post to remove the factual inaccuracies.
Real ear responses are measured with a CALIBRATED probe tube, that removes the tubing resonances. There are several mics used to cross check this on most systems.
Your assertion about tube collapse is also inaccurate, as there is adequate ‘give’ in the skin at the canal surface. Blocking a vent or a slot vent channel with the probe tube would render the test meaningless for low frequency response. It’s very misleading to say that ‘the truth’ is X or Y especially when you are being some excellent clinic evidence to the contrary. Ricketts, Moore, Dillion and Vonlanthen et all have spent years to improve the quality of the fittings we get today: sweeping them aside with a stupid counter-science argument does you no credibility at all.
If you actually wanted to challenge the veracity of REM measurements, there’s a few ways you can make a good case. Namely:
1 The original Audiogram: how accurate is it (and therefore your subsequent target)? Threshold measures are repeatable for some people, but not for everybody. Anyone on here who regularly tests hearing will know that there are patients who ‘wander’.
You have also got to consider whether the test was done in noise, with ear-tones or cans, how long ago etc.
2 The probe tube - has to be placed in the last 6mm of the ear canal - not impossible, but it’s one of those jobs where an extra hand would be useful, especially if you have a programming lead on the aid. Due consideration for the condition of the ear canal, whether the patient has wax, a cold, a middle ear infection.
3 Target and stimulus tone. People swear by automated speech weighted noise and pseudo random noise. They will also say that a NAL target is better than a DSL. Personally I have massive reservations about using ANY form of stimulus that isn’t real speech. Hearing aids are inherently designed to filter noise from within speech channels: if you reproduce a signal or modify it, it contains noise - the aid WILL turn itself down. The best results will always come from straight speech input: not everybody uses this.
4 Loudness experience and patient expectation. Some patients just don’t like where the prescription sits, even when you’ve successfully negotiated all the above. Dealing with this can be difficult: the patient may feel left out of the programming loop or they may just want a different level of loudness than you’ve arrived at. You have to bear this in mind and soften or louden the settings accordingly. However, it is usually possible to wean them to nearer their prescription over several visits. Other patients sit miles away from their target and are quite happy.
5 Temporal aspects within signals that you can’t ‘see’. Different manufacturers use different attack and release times as part of their processing strategies, they will make the aid sound different or unnatural, BUT you can’t necessarily visualise the response - even on the 3D systems it’s not that clear.
Now, you can take on these arguments or disregard them in respect of your ‘truth’: however I used to work for a distributor selling the Oto-wizard in the UK as such I was first point of call on training, trouble-shooting and demonstrating the systems. REM is a hugely helpful tool, not to recognise that is just daft.
I was not specific enough in my descriptions of formulas. Fitting formulas such as NAL-NL1, NAL-R, DSL v5, POGO etc. are developed by researchers. Standard real-ear machines compare against these data-based formulas (developed through testing and research with ACTUAL wearers).
The formulas in use by the manufacturers are based off of these types of formulas. The manufacturers apply some changes to their own fitting formulas that affect the first fitting of the hearing aids.
What I am doing when I perform a REM is measuring the ACTUAL sound production of the hearing instrument in a persons ear and comparing it against the RESEARCH based fitting formulas.
I can see how some others have taken some offense at your statements. REM have been in existance for many years and have countless hours of research involved in the development of formulas and the verification of results. By saying they have no value you are discrediting the work done by many doctors and graduate students. As a hearing professional it is our goal to improve the hearing of people. So many hours would never have been put in if REM had no value.
As a relative newbie to these matters having worn a HA for about 7 years, I bring and end users view on this matter. Having read the arguments for and against REM it would seem totaly illogical not to carry it out, as it is just another tool to fine tune the audios programming of an aid. Why would anyone want to argue against it when, at the very worst, it might not be beneficial. The benefits on the other hand could be immense. Surely its a no brainer.
I agree with the comments that you may never know the benefits of having it done. Your may find your aids acceptable, but are they the best they can be? A simple analogy could be my last car which was perfectly adequate as it came out of the factory. I did however employ a specialist company to re-map the engine management system and it transformed the car from the adequate to outstanding.
For me I will be insisting on REM when I purchase my next aids which hopefully will be some time in the near future.
Many thanks for all the information it is so useful.
I have always thought that the Achilles Heel of the REM system is that the target audiogram itself is, to my mind, very suspect for severe/profound patients.
False patient responses to tones at high levels is well documented.
For this group, I believe, the only valid meaningful test is speech comprehension. Ed
I really think this thread is a lesson in the importance of consumers educating themselves.
I wanted to read up on REM as its been suggested I have my fitter try it, and now after reading this thread I am starting to question how decent my fitter is. I have oticon ino, open fit, RITE.
When the aids came in the fitter used the Oticon program, adjusted for feedback, and she asked me to speak to adjust for my voice. Then that was it.
I came back a week later telling her I was having problems hearing men (I could even hear some news channels on TV at lower volume better without the aids), and so she added in some lower frequency tones by tricking the Oticon program into thinking I had different domes. She set the aids to better fit my hearing loss (something to do with the Oticon program). It took all of five minutes. That was it. edit: I notice no difference.
Outside of my adjusting to sounds I haven’t heard for a while, I don’t have this sense I am getting out of the aids what I should. I often can’t hear people three feet away from me if there is any noise at all. I hear the TV better sometimes (not always) if I turn it up without the aids on than I do with them off.
The long and the short of it is: I am clueless. I have no idea what is good or bad. I don’t really have the option of shopping around (I could only afford aids by going through a not-for-profit discount program as I am in school), but man I would love to.
The Web says inertia, but I know in a rotational mech. system it is a rubber coupling, e.g., the harmonic balancer that couples the flywheel to the engine crankshaft.
T.C. Gordon Wagner clued me in to this stuff. That was about the most difficult course I ever took and he was brilliant (and hard to follow).
This stuff is useful for designing loudspeakers, mics and phono cartridges, where you have to bridge the gap between the mech. and elec. domains.
The engineers who model the systems do it in the same way, but you have to consider that every function has resistance AND capacitance which varies with frequency. This gives you Z or impedance in ohms as a function of frequency. In the physical world the property is called ‘reactance’. Basically it’s all pendulums and masses, you’re either altering the length of the string or you change the mass.
I found this discussion quite useful to me as a soon-to-be HA user. REM seems to be a valuable tool in the process. Does anyone know if a typical Costco does REM? I pick-up my HA tomorrow and have been reading so I know what to expect and how I might contribute to the process.
Well, my Costco which is in small city (about 75k) did REM when I picked up my HAs today - glad that is a tool that they use in the fitting procedures.
REM, IMO for every set of aids going out the door is a waste of time. first you need to know how accurate your audio-gram is. REM is good if for some reason you are not getting the results you expect from the software. a bad receiver, processor, whatever. you could do a REM and verify you are getting exactly the output you expect vs the audio-gram but maybe it would sound like crap to the user. as always your mileage will vary. with your numbers I would be looking at RICs with molds.
IMO, it doesn’t matter what you do, if the audiogram is wrong the outcome is going to be terrible BUT if your audiogram is correct then using REMs to fit to evidence-based targets has been proven to improve client satisfaction and reduce the average number of follow-up appointments on average from 4 -6 without REMs to 1 -3 with REMs. If you want to save time and get better results first time, performing REM is a benefit to your client, and your practice. There is plenty of evidence to support their use. It’s a mystery as to why so many dispensers of hearing aids continue not using them in the USA. The following is an article that you might find useful: http://www.audiologyonline.com/articles/20q-probe-mic-measures-12410.
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IMO, it doesn’t matter what you do, if the audiogram is wrong the outcome is going to be terrible BUT if your audiogram is correct then using REMs to fit to evidence-based targets has been proven to improve client satisfaction and reduce the average number of follow-up appointments on average from 4 -6 without REMs to 1 -3 with REMs. If you want to save time and get better results first time, performing REM is a benefit to your client, and your practice. There is plenty of evidence to support their use. It’s a mystery as to why so many dispensers of hearing aids continue not using them in the USA. The following is an article that you might find useful: http://www.audiologyonline.com/articles/20q-probe-mic-measures-12410.
opinions are like… every has one. I work at the VA and have more equip available to me then 10 practices. get more continuing education then most private practice AuDs. if my client satisfactions surveys were not next to perfect there are a whole list of AuDs wanting to get into the VA. I adjust the aids to make my the clients happy not to some perfect number that may or may not sound good to the client. as far as finding your link useful if I cared to waste time I’m sure a could find a link to an article that says the opposite. everyone has to run their railroad however they see fit…
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opinions are like… every has one. I work at the VA and have more equip available to me then 10 practices. get more continuing education then most private practice AuDs. if my client satisfactions surveys were not next to perfect there are a whole list of AuDs wanting to get into the VA. I adjust the aids to make my the clients happy not to some perfect number that may or may not sound good to the client. as far as finding your link useful if I cared to waste time I’m sure a could find a link to an article that says the opposite. everyone has to run their railroad however they see fit…
Newbie here I have a simple question. Is the REM when done used for all hearing aids or just the ones that fit inside your ear? Hope thats not a dumb question.
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Newbie here I have a simple question. Is the REM when done used for all hearing aids or just the ones that fit inside your ear? Hope thats not a dumb question.
