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).
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:
Observer scale
The Observer scale includes the following items. Each item includes category boxes. The categories are for descriptive purposes only.
Frequently asked questions
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.
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 commercial license, please contact us for further information.
For the use of the POSAS 2.0 the following article must be referenced: van de Kar AL, Corion LU, Smeulders MJ et al. Reliable and feasible evaluation of linear scars by the patient and observer scar assessment scale. Plastic Reconstructive Surgery. 2005;116:514-522
The POSAS 2.0 can be translated by researchers. The POSAS 3.0 can only be translated by certified translation agencies. For permission regarding the translation of the POSAS, please contact us via the contact form.
Yes, as of May 2020 a license agreement is mandatory for both the POSAS 2.0 and 3.0. Request a license.
Yes, in the case of non-commercial use a fee is required for the use of the POSAS. Read more about licensing.
Yes, this is possible. An annual subscription-based license agreement grants the rights for digital use of the POSAS.
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.
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. Therefore, if the aim is to evaluate scar quality, the sum score must always be used.
The Patient Scale and the Observer Scale are two separate instruments that measure quality from different perspectives, and, therefore, are complementary to each other. The sum score of both instruments provides no additional meaning.