User instructions POSAS 3.0
5-point score
The different POSAS 3.0 questionnaires:
- POSAS 3.0 patient scale
- POSAS 3.0 observer scale
The generic scar version can be used for all types of scars, except for ‘linear’ scars that have a linear shape and are often the result of a (surgical) incision. The linear scar version of the POSAS 3.0 can be used for those scars.
Each item of the POSAS 3.0 is rated on a 5-point score. The lowest score is ‘1’, which corresponds to the situation of normal skin (i.e. normal pigmentation, no itching). Score 5 equals the largest difference from normal skin (i.e. the worst imaginable scar or sensation).
Not suitable for photographic assessment
The POSAS is not suitable for photographic evaluation, as some of the characteristics are impossible to evaluate on the basis of photographs alone. For example, palpation of the skin is necessary to provide a sound assessment.
Frequently asked questions
For the use of the POSAS 3.0 the following article must be referenced:
Carrière, M.E., Mokkink, L.B., Tyack, Z. et al. Development of the Patient Scale of the Patient and Observer Scar Assessment Scale (POSAS) 3.0: a qualitative study. Qual Life Res (2022). https://doi.org/10.1007/s11136-022-03244-6
The POSAS 2.0 can be translated by researchers. The POSAS 3.0 can only be translated by certified translation agencies or by a researchs group experienced with translations. Please contact us and we help you with the procedure. For permission regarding the translation of the POSAS, please contact us using the contact form.
Although the POSAS was not developed for scar quality measurements in children, we believe that the adult POSAS version would be acceptable for use within adolescents (15 years and older). However, future studies must be undertaken in order to validate this hypothesis. The next step of the POSAS research team is to develop a POSAS-kids version, enabling reliable and valid scar quality measurements in young children.
No, we do not encourage using parents as a proxy if children are too young to complete the POSAS independently. The next step of the POSAS research team is to develop a POSAS-kids version, enabling reliable and valid scar quality measurements in young children.
Unfortunately, the M(C)ID of the POSAS 2.0 has not been established yet. Currently, various measurement properties of the POSAS 3.0, including the M(C)ID, are being evaluated using an international field test study.
The POSAS 2.0 was initially developed for burn scars, but has been validated over the years for multiple other types of scars. The POSAS 3.0 has been developed for all types of scars, such as scars caused by burns, surgery, trauma, acne, as well as keloids.
The different strategies include:
– scoring the scar on average
– scoring the worst part of the scar (in terms of complaints or visually)
In general, the best strategy depends on the research or clinical question. This should be discussed at the start of your project, or before you start using the POSAS in the clinic, to make sure that the same scar area is assessed. It is also important for observers and patients to score the same scar area.
POSAS measurements may be less valid in this case, because some of the included scar characteristics are rated based on the extent to which they differ from the patient’s normal skin.
The construct of the POSAS (i.e. what it aims to measure) is scar quality. Scar quality is formed by the scar characteristics included as items in the POSAS. We are currently working on a total score, where different items will receive different weights, and will add this information as soon as it becomes available.
The main reasons for the initiation of the project to develop the POSAS 3.0, was the lack of input by patients and international professionals in the development of the POSAS 2.0. This third POSAS version is developed to measure scar quality in patients with all types of scars, including those caused by burns, necrotizing fasciitis, acne, trauma, or surgery. The Patient Scale has been developed using a series of focus group meetings that took place in the Netherlands and Australia. The Observer Scale has been developed using a systematic method to reach consensus among experts. The POSAS 3.0 contains more items to gain deeper insight in scar quality.
As explained above, the POSAS 3.0 has been developed with patients and international professionals in the field of scar quality and measurement. The POSAS 2.0 will still be available until one year after the launch of the POSAS 3.0. It is recommended to use the POSAS 3.0.
If you would like to use the POSAS 3.0, please apply for a new license. If you currently have a commerical license, please contact us for further information.
Observer and patient scales
The POSAS measures scar quality and consists of two parts: the Patient Scale and the Observer Scale.
Patient scale
The Patient scale includes the following items:
Colour
Shininess
Raised/sunken scar
Hardness
Irregularity
Sensitiveness
Numbness
Pain
Shooting sensation
Burning sensation
Itch
Tingling
Scar tightness at rest
Tightness during movement
Fragility
Dryness
Overall opinion
The overall opinion of the patient on the overall severity of their scar.
Observer scale
The Observer scale includes the following items. Each item includes category boxes. The categories are for descriptive purposes only.
Vascularity
The increased vascularization of the scar causes color changes (pink, red, blue or purple), which can be eliminated by pressing on the skin tissue with your finger or Plexiglas.. This is a good indicator of scar activity in the early maturation phase. Over time, scar activity will diminish and the redness will (partly) disappear.
Categories: pale/white | pink | red | purplePigmentation
The light (hypopigmentation) or dark (hyperpigmentation) color of the scar, which remains after eliminating the influence of the vascularization on skin color by pressing on the scar with your finger or Plexiglas. Pigmentation disorders are caused by variation in the concentration of melanocytes in the epidermal layer and their melanin production. Significant pigmentation disorders will most likely remain in the long term.
Categories: hypo | hyper | mixSurface level
The observer’s rating of the degree to which the level of the scar surface is different to the level of unaffected (surrounding) skin. The level of the scar surface can be higher (elevated) or lower (depressed) than the level of the unaffected skin. In some cases, both elevation and depression occur. This can be assessed by inspecting and touching the scar.
Categories: elevated | depressedSurface texture
In scars, the surface texture is often times more irregular (i.e. more bumpy and rough) than unaffected skin. In some cases, the surface of the scar can be overly and abnormally smooth (even smoother than unaffected skin).
Categories: irregular | overly smoothFirmness
Firmness is evaluated by picking up a scar, pinch it between thumb and index finger, and rolling it between the fingers like normal skin. Firm scar tissue is less supple and flexible, which makes it difficult to pinch.
Adhering
In adhered scars, the movement of the skin in relation to the underlying structures is limited, as a result of being either partially or completely fixed to deeper structures.
Tension
The amount of tension on the scar area can be assessed best when the patient’s maximum range of motion is actively achieved in a neighbouring joint. Signs of tension include tightness of the skin, tension lines (banding), discolouration (blanching) of skin colour, and a limited range of motion.
Overall opinion
The overall severity of the visual and tactile characteristics of the scar.