FAQ

To be able to use a Borg scale you need to obtain a license and pay applicable fee. See How to obtain for more details about the process.

The correct scale to use is the Borg CR scale® (CR10) that Gunnar Borg has developed and that is extensively used all over the world.

On the page How to obtain you will find the translations that are available for the different scales.

As you may know, there are different types of Borg Scales. Firstly, the original perceived exertion scale (the Borg RPE Scale®) from 6 – 20 and then the Borg CR10 Scale®, a general intensity scale for scaling most kinds of perceptions and symptoms. There is also a more finely graded CR scale, the Borg centiMax Scale® (also called CR100). All scales are easy to use and to understand and give reliable and valid data, but usually for somewhat different purposes.

 

The advantage with the Borg RPE scale is that it because of its construction gives data that grow approximately linearly with HR (and oxygen consumption) during steady state work on a bicycle ergometer.

The Borg CR scales® (CR10 and centiMax) are general intensity scales that can be used for many kinds of symptoms. A great advantage with the Category-Ratio (CR) scales is that they are Level-Anchored Ratio Scales that combine the value of verbal anchors for level determinations (How strong?), with ratio data (How much stronger?) giving results similar to what is obtained with magnitude estimation (S.S. Stevens). With ratio data, of course, it is possible to also answer more interesting research questions and apply more advanced statistical analysis. When the correct instruction is used with the scales, Gunnar Borg’s “Range-Model” for intra- and interindividual comparisons applies to the ratings by calibrating subjects with a maximal perceived exertion (of lifting something close to maximally heavy) as a “fixed star”. In this way, direct comparisons between individuals and among different symptoms are possible.

Of the two CR scales, the Borg CR10 scale is the older and most widely used. It has been used clinically, in ergonomy, and in sports and training for assessing perceived exertion, leg fatigue, breathlessness, dyspnea, and aches and pain in muscles and joints. The Borg CR10 scale is the scale recommended by the ATS (2002) for the 6-minute walk test, and by ACSM (2010).

The Borg centiMax scale® (CR100) is a CR scale from 0 to 100, and is thus more finely graded than the CR10 scale. It can be used in any situation where the CR10 scale is used and would be the choice if it, for example, is important for the patient or athlete to be able to give more detailed, finely tuned answers. The centiMax scale has also been used for example for estimating putting force in golf, performance evaluation in diving, in voice perception of hypernasality, in aircraft noise perception and in assessment of depressive symptoms.

For reference, see for example: Borg, G, 1970; Borg, G, 1982, 1998; Borg, G & Borg, E., 1994, 2001; Borg, E., & Borg, G., 2002, 2013; Borg, E., 2007, Borg, E. & Kaijser, 2006; Borg, E., Borg, G., Larson, Letzteer, Sundblad, 2010; Borg, E. & Love, 2017; Borg, E., Magalhaes, Costa, Mörtberg, 2018; Dickson, C., 2009; Molander, Olsson, Stenling, Borg, E., 2013; Yamashita, Borg, E., Granqvist, Lohmander, 2018.

BorgPerception AB has copyright and trademark for the different authorized Borg Scales and the instructions that go with them.

There are many so called “modified Borg scales” that are forgeries and we cannot give permission or encourage the usage of them. On some there are words that have been exchanged and on others there have been things added, for example colors or pictures, and all this threatens to distort the responses from the scale. The verbal anchors on the Borg Scales have been carefully chosen and placed at their numerical position so that the scale is constructed to give ratio data that corresponds to what is obtained with a psychophysical scaling method called magnitude estimation (that on group level has been shown to give ratio data). See, for example Borg, G., 1998, Borg, G., and Lindblad, 1976.

Another problem with some modified scales is that the dot (•) above 10 at “absolute maximum” has been removed. This may also distort data and induce a so called “ceiling effect”.

On some scales (often called “Borg dyspnea scale”) the word “strong” has been replaced with the word “severe”. This is not good, because the word “severe” does not have a neutral – but instead negative – connotation. If I, for example, have a severe pain, it is likely to be regarded as a serious problem. However, a pain can be “strong” without being at all severe… (for example a strong muscle pain from hard exercise).

Sometimes one can find that horizontal lines have been drawn to introduce categories on the scale (for example for each scale value.) This will likely prevent participants from using decimal points, and may risk reducing the data quality.

Even introducing only a few (for example 2-3) categories, might cause a problem in that it creates “jumps” in the data where data clusters just below each limit. (Similar to a ceiling effect, but for sub-maximal levels.)

Using colors on the scale is problematic because colors have multiple meanings. Different hues do not have an intensity variation that is congruent with the meaning of the verbal anchors. Colors may also symbolize as well as trigger different emotions, they are used for specific information (red = stop, green = go), and they have symbolic meaning that differs between different cultures (in Western culture red can mean “danger”, in the Chinese culture red can mean for example “luck”). Thus individual interpretation of the colors may covary in an unknown way with the responses.

The Borg CR10 scale is also a general intensity scale. This means that there is no need to modify the scale in order to adapt it for specific symptoms (with one scale for exertion, another for pain, one for breathlessness, dyspnea, etc.), but the same scale can be used for any symptom that has an intensity variation. So, with a correct administration and instruction, the Borg CR10 scale, can be used for perceived exertion, pain and dyspnea, and also for motivation, depression, anxiety, or loudness, taste, smell, etc. And the values can be compared intra-individually and even inter-individually (so that if I rate my perceived exertion as 8, and my pain as 4 and my dyspnea as 2 and depression as 1, this means that I am twice as exerted as I have pain, and my pain is 4 times as strong as my feelings of depression (etc.). So, actually, you only need the correct Borg CR10 scale. (The same reasoning is true for the Borg centiMax scale.)

Probably the most common usage of the Borg scales are either in a clinical setting with patients or healthy participants, in rehabilitation, or in sports, exercise and physical training, and with work on a bicycle ergometer or treadmill (or similar). It is then important that the patient or participant (P) is familiarized with the scale. The test administrator (TA) shall read the whole instruction and P shall be given a chance to ask questions if anything is not clear. It is especially important that P understands the reference level “Maximal” and how it is anchored in a previously experienced maximal exertion. It is also important for P to understand the importance of always starting with looking at the verbal anchors, but then to report a numeric response (see Scale instruction). It is an advantage if the instruction is at hand for P to be able to look at during any stage of the test.

One important basic principle behind the Borg CR scales is that “10 Extremely strong – Maximal” should, according to Gunnar Borg’s Range-Model be anchored specifically in a maximal perceived exertion. And that this should be used also intermodally. This will then work as a general anchor (a “fixed star”) and function to calibrate participants. A maximal breathlessness might not have the same average intensity across individuals as perceived exertion has (even if I suspect it would probably be rather similar). Anyhow, with two different definitions of “maximal” there is a risk that these are not equivalent. Therefore, having different instructions might risk to “weaken” the possibility for inter-individual and inter-modal comparisons.

Secondly, and perhaps more importantly, I is very seldom necessary with additional instructions. The concept of “perceived exertion” is a “global” feeling that integrates both feelings of tiredness and muscle fatigue as well as breathlessness and shortness of breath, and several other “cues” from the body that tells you that your body is working and adds to the feeling of exertion. In my thesis, for example, participants made ratings of 19 different bodily cues related to perceived exertion after having only the general instruction…. The instructions says:

“When rating exertion give a number that corresponds to how hard and strenuous you perceive the work to be. The perception of exertion is mainly felt as strain and fatigue in your muscles and as breathlessness or any aches.”

Therefore, also, the examples given for the different scale values describe this general feeling of exertion and the activity level. For example:

“As taking a shorter walk at your own pace.”

“You can still go on, but you really have to push yourself and you are very tired.”

A third reason is that there are also several nuances in respiratory symptoms. For example, “breathlessness” is what all of us experience when exercising, but “shortness of breath” may be closer related to respiratory distress and difficulties breathing, and therefore something that is not experienced by everyone, not even on a very high work load.

My suggestion is therefore that you use the same instruction for both aspects of perceived exertion (both fatigue and breathlessness). But when you have read the full instruction to the participant you add the following.

“The overall perception of exertion can be felt in your body mainly as strain and fatigue in your muscles and as breathlessness or perhaps some shortness of breath. We now want you to give ratings of these two aspects separately.”

The “•” and “Absolute maximum” is one of the unique features with the Borg CR10 scale. In the instruction to the patient it says for this level:

Is ”Absolute maximum” for example ”12” or even more. 

So, while 10 – Extremely strong, “Maximal” is anchored in the patients previous experience of a maximal exertion, a level that is well schematized and thus works best as the main reference level (and the anchor with the least intra- and also inter-individual uncertainty), this might not be the highest possible level. Most people will not need to give ratings above 10, but in order to prevent a ceiling effect and truncation of data towards the upper part of the scale, it has ot be open and allow for values above 10 in rare cases.

Let’s take an illustration: when measuring how tall a person is there is no upper limit to the scale. Most people are not as tall as 200 cm (6.6 ft). But, if we needed to put a limit on the scale, would this be it? Even fewer are above 220 centimeters (7.2 ft)… But, what if someone is 222 cm (7.3 ft)…? Etc. But, of course, there is an upper limit. No one would ever be 300 cm (9.8 ft). The tallest ever living man was 272 cm (8.9 ft)…

So, the same here. Of course, there is an upper limit to what can be reasonable. For example, a perceived exertion cannot be twice as heavy (20) as your previously experienced maximum. And also 50% more would be extremely unusual, and almost only possible for someone who has lived an extremely inactive life and never really exercised at all (and then also probably does not have a stable picture of his/her own previous maximum). So, if you need to put an upper limit, I would say that anything above 15 is probably not valid. But, also, several groups of patients should usually not be pushed above 7/8 on the scale (depending on their condition).

Yes. The Borg scales are today used in Licensee internal apps and and computer programs. BorgPerception supports the licensee in initial phases, with appearance and usage aspects, and in final review and approval of screen dumps.