Choosing a Skin Firmness Treatment in Daegu — What Is “Firmness” Measured With?

The conclusion, first

“Where in Daegu is good at firmness treatments?” is a question that cannot be settled from public data. There is no public metric comparing practitioners’ skill, reviews cannot be used as evidence of effect under the Medical Service Act, and a count of procedures performed is not the same thing as proficiency. So we write a different answer instead — we set out how far the word “firmness” has actually been measured in the data, and we say what we decide on. There are three points. First, among the values produced by the standard instrument for measuring firmness (the Cutometer), the parameters that carry the name “elasticity” are three — R2, R5 and R7 — and they measure different things. Second, the reproducibility of that measurement depends heavily on “who is measuring” and on “whether the probe is lifted off and replaced” — when one person repeats the measurement the intraclass correlation coefficient is above 0.90, but when the examiner changes it falls to the 0.50s, and measuring continuously without lifting the probe takes a value of 0.83 down to 0.48. Third, the study that established that reliability was carried out on the arms and legs, not on the face. So a figure such as “firmness improved by so many per cent” cannot be interpreted unless it is written down together with which parameter was measured and by what procedure.

The order we actually work through in consultation

1. We check in a sentence what “firmness” is pointing at

In the consulting room “firmness” usually means one of three things — the feel of the skin springing back when it is pressed with a finger, the shape of a facial contour that has settled downwards, or the impression that the surface of the skin looks thin and without strength. These three sit in different layers, and therefore belong to different classes of treatment. The force that springs back is a matter of the dermis; the shape that has settled is a matter of the fat and fascia beneath the dermis; the impression of thinness is a matter of thickness. Skip this distinction and different goals end up mixed under the single name “firmness treatment.” The layer-by-layer detail we have written out separately in wrinkles and firmness are not the same thing and when you feel your skin has lost its firmness.

2. We say what the values on the instrument are

These come out of the same measurement, and yet their numerators and denominators differ. So the sentence “firmness improved” may mean that R2 rose, or that R7 rose, or that the two moved in opposite directions and only the one that improved was written down. When we cite any data we try to write the name of the parameter alongside it — because there is no way to interpret material that says only “elasticity up 15%” with no name attached.

3. We tell you how much that measurement moves about

In a study that set out to establish a standardised method of measurement (10 healthy adults, four sites on both sides — upper arm, forearm, thigh and lower leg — and two trained examiners), the intraclass correlation coefficient when one person repeated the measurement was above 0.90 at every site, but when the examiner changed it was at the level of above 0.50. In their conclusion the authors wrote that “proportional error was observed, so the limits of agreement should be taken into account.” In a separate study (54 people), lifting the probe off and replacing it for each measurement gave an intraclass correlation coefficient of 0.83, while measuring continuously without lifting it gave 0.48 (p < 0.001). That is to say, a single step in the measurement procedure halves the reliability.

Neither study was carried out on the face. The first was on arms and legs; the second was repeated measurement in a rehabilitation and plastic surgery clinical setting. We could not find data establishing inter-examiner reliability on facial skin — this does not mean “there is none”; it means we were not able to verify it.

4. We look at where the weight of the registered trials sits

In the clinical trial registry, 89 trials carry “skin elasticity” as their condition, and 202 carry “skin laxity or facial sagging” (as of the point at which we checked). That is, what industry and academia actually spend money measuring is closer to “sagging” than to “firmness.” And a considerable proportion of the sagging trials are sited on the submental area and the neck — not the cheeks and midface. We have written this out separately in facial sagging in Daegu: which layer the treatment works on, first.

5. We distinguish an increase in thickness from a rise in elasticity

That the dermis has thickened and that the force springing back has strengthened are two different statements. In a study that biopsied at one year after a single injection of liquid polycaprolactone into the dermis (13 people · single clinic · the right temple left untreated as a control), the thickness of the biopsy specimens was reported to have increased by an average of 26.74% ± 9.26% (1,412 ± 69 µm → 1,781 ± 110 µm, p < 0.001). Facial skin thickness measured by ultrasound increased by 21.31% ± 4.34%. This study measured thickness; it did not measure elasticity parameters. We could not find data confirming in people that an increase in thickness leads to an increase in the force that springs back.

6. So this is the order we decide in

We do not begin by choosing “a treatment that is good for firmness.” The order is this — (1) we separate out whether it is the force springing back, the shape that has settled downwards, or thinness → (2) if it is thinness we put the classes that increase thickness on the list of candidates, and if it is settling downwards, the classes that work on a layer → (3) for each candidate we tell you what has been measured in people and how many people the sample was → (4) items that have not been verified (dose · number of sessions · duration) we say have not been verified → (5) and on top of that we decide together. Price and discounts enter nowhere in this order; costs are explained separately at the consultation.

Five things worth asking at a consultation

These are questions you can ask at any clinic. If the answers are specific and the place says it does not know what it does not know, that helps a judgement.

1. “In my case, which layer is the firmness problem in?” — an answer should come back saying which of dermis, fat or fascia is meant.
2. “Which parameter was the firmness improvement figure for that treatment measured with?” — whether it was R2, R5 or R7, or whether it was not an instrument reading at all but a photographic assessment.
3. “How many people was that evidence based on?” — whether it is animal or in-vitro material or human material, and whether there was a control group.
4. “What is the basis for the duration?” — whether the follow-up actually ran that long, or whether it is an estimate.
5. “In what circumstances might it not work?” — an explanation that does not state the limits is not material for a judgement.

What is confirmed / what is inferred / what we could not confirm / material pointing the other way

Where this article was written

• Miso Clinic, Daegu · 4F Bombom Building, 125 Dongdeok-ro, Jung-gu, Daegu, Republic of Korea (near Kyungpook National University Hospital station)
• Director Lee Chi-Hak · Tel. 053-428-2700
• This column was written by the director and reviewed in September 2026.

This article was written not to recommend a particular treatment but to set out the extent of the data needed for a decision. Judgement about an individual condition requires examination, and this article does not substitute for medical care. As companion pieces it helps to read collagen boosters in Daegu — where “it increases collagen” was measured and facial sagging in Daegu: which layer the treatment works on, first.

Frequently asked questions

Who wrote this

References

1. Inter-examiner reliability of elasticity measurement — Fujimoto Y, Yuri Y, Kato Y, Kinoshita S, Tamiya H, Annals of Medicine 2023;55(2):2279747, PMID 37967233, DOI 10.1080/07853890.2023.2279747. 10 healthy adults · both upper arms · forearms · thighs · lower legs · two trained examiners. R0 · R2 · R5 · R6 · R7 measured. Intra-examiner intraclass correlation coefficient (1,1) > 0.90, inter-examiner (2,1) > 0.50. The authors wrote that proportional error was observed and the limits of agreement should be taken into account. This is material from the limbs, not the face, and the sample is 10 people.
2. Material in which the way the probe was applied split the reliability — Bonaparte JP, Chung J, Journal of Medical Engineering & Technology 2014;38(2):85–89, PMID 24446801, DOI 10.3109/03091902.2013.876111. 54 people. Lifting the probe off and replacing it for each measurement gave an intraclass correlation coefficient of 0.83; measuring continuously without lifting it gave 0.48 (p < 0.001). A study showing that the measurement protocol itself acts significantly on the result.
3. Human biopsy material on increased dermal thickness — Kim JS, Aesthetic Surgery Journal 2019;39(12):NP484–NP494, PMID 30778526, DOI 10.1093/asj/sjz050. 13 people · single clinic · prospective. 0.5 cc of diluted polycaprolactone filler injected once into the facial dermis, with the right temple left as a within-person untreated control. At one year, temple biopsies (117 points in 13 people) showed a thickness increase of 26.74% ± 9.26% (1,412.41 ± 69 µm → 1,781.11 ± 110 µm, p < 0.001), and facial skin thickness measured by ultrasound an increase of 21.31% ± 4.34%. Three people had additional biopsies at two weeks and at four years. It is a single author · a single institution · not randomised, and what is measured is thickness, not an elasticity parameter.
4. First report of human tissue findings for liquid polycaprolactone — Kim JA, Van Abel D, Journal of Cosmetic and Laser Therapy 2015;17(2):99–101, PMID 25260139, DOI 10.3109/14764172.2014.968586. A pilot study of 2 patients. Biopsy 13 months after injection confirmed collagen formation around the particles. The sample is 2 people and there was no control group.
5. Where the weight of registered clinical trials sits — ClinicalTrials.gov search by condition. “skin elasticity” 89 trials, “skin laxity OR facial sagging” 202 trials (as of the point at which we checked). The sagging trials are concentrated on the submental area and neck. These are figures within the range we checked and will differ with the date of the search.
6. Individual variation in human facial skin and superficial fat thickness — Lee KW, Yoon JH, Kim JS, Hu KS, Kim HJ, Clinical Anatomy 2021;34(7):1050–1058, PMID 33583088, DOI 10.1002/ca.23726. 30 cadavers from Korea and Thailand, 11 paths measured with a three-dimensional scanner. Skin 2.1 ± 0.4 mm, superficial fat 5.2 ± 1.9 mm — the standard deviation reaches 36% of the mean. This is material from fixed cadavers, so it may differ from thickness in the living.
7. Legislation on medical advertising — Article 56(2) of the Korean Medical Service Act. It prohibits advertising by means of accounts of treatment experience, comparison with other medical institutions, superlative expressions and the like. This is why this column carries no expressions such as “good at” or “the best,” no comparison with other medical institutions, and no prices or discounts.