User instructions

10-point score

Each item of the POSAS is rated on a 10-point score. The lowest score is ‘1’, which corresponds to the situation of normal skin (i.e. normal pigmentation, no itching). Score 10 equals the largest difference from normal skin (i.e. the worst imaginable scar or sensation).

The total score of both scales can be simply calculated by summing up the scores of each of the six items. The total score can range from 6 to 60. The overall opinion item is not included in the sum score.

Frequently asked questions

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

Yes, a list of all the available languages can be found on the page About POSAS.

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 using 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.

Observer and patient scales

The POSAS 2.0 measures scar quality and consists of two parts: the Patient Scale and the Observer Scale. Both scales contain six items of scar quality.

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, and are not included in calculating the total score of the POSAS.