Visual Assessment and the Use of the Scar Cosmesis Assessment and Rating Scale (SCAR Scale) for Facial Linear Scars
28 July 2017 (online)
I read with great interest the outstanding manuscript by Collins et al. The authors should be commended for taking a novel approach to scar ratings and assessing for the presence of a systematic difference between patient and physician ratings. The authors cite earlier work developing the Patient Attitudes to Scarring Scale (PASS). As noted by the authors, that was the first scale designed to prioritize patient concerns regarding scars, an important prerequisite for developing meaningful outcome measures.
Subsequent to the PASS study, the SCAR (scar cosmesis assessment and rating) scale was validated and reliability tested as a feasible, reliable scale that could be performed in less than 30 seconds.  The SCAR scale addressed many of the shortcomings discussed by the authors, and it includes patient assessments for pain and itch; it does not include separate clinician and patient ratings for the same domains. As noted by the authors, though there was indeed a difference between clinician and patient ratings, this difference appeared to be systematic, so that significant additional information on overall scar quality may not necessarily be gained (and feasibility may be significantly compromised) by including both sets of ratings.
The SCAR scale also addresses the authors' concern regarding overshadowing, as a single question regarding the scar's desirability is included as a gestalt assessment of scar quality. The SCAR scale reliability study included a diverse group of patients with Fitzpatrick skin types I–VI. A visual rating scale may ideally address the differential appearance of scarring in various skin types.
The use of anchor cards to create a visual assessment is an interesting approach and may be helpful for patients who do not have an a priori idea of what an idealized scar should look like. It also addresses a central shortcoming of most earlier scar assessment scales: the nebulous language used in their various domains.
The range of scars included in the anchor cards was fairly tight; in other words, no truly widespread or hypertrophic scars were included among the final four cards. Though this speaks volumes regarding the authors' outstanding surgical skills, it may not generalize well to surgical procedures performed by others or where significant hypertrophy or spread may be seen, because any undesirable outcome would simply be classified as being worse than the worst cared (level 9). Thus this approach may fail to discriminate between a spread scar (undesirable), a widespread scar with suture track marks (even less desirable), or a hypertrophic scar or true keloid (least desirable).
The authors had patients quantify their own scar scores on a 1–9 scale based on anchor cards; as with the Patient and Observer Scar Assessment Scale (POSAS)'s 10-item scales, using a 9-item scale for patients—even one that is anchored to photographs rather than written criteria—may introduce biases such as central tendency and underlying cause, though I agree with the authors that photographs likely help mitigate these concerns.
Whether patients are better or worse at assessing their own scars versus those of others is a fascinating question raised by the authors and it certainly merits future study. Anticipatory preprocedure anxiety may affect patient ratings; though as all patients' scars were at least 3 months old, this was unlikely to be a significant issue. The authors should be lauded for their excellent contribution to this important area.