Many Psoriasis Clinical Practice Guidelines Unable to Demonstrate High Quality

doctor reading file
doctor reading file
A systematic review and comprehensive critical appraisal of guidelines for psoriasis is performed.

Using multiple critical appraisal tools, researchers have found that most clinical practice guidelines on psoriasis that have been published since 2015 are unable to consistently demonstrate high quality.

Only a single European guideline on the treatment of psoriasis vulgaris was appraised as having “excellent quality” across all Appraisal of Guidelines for Research and Evaluation (AGREE) II domains, raised no Lenzer’s red flags, and possessed greater trustworthiness according to the United States Institute of Medicine’s (IOM) criteria. Findings from the research were published online in the British Journal of Dermatology.

Critical Appraisal Tools

According to the investigators, critical appraisal is among several methods to determine the quality of clinical practice guidelines, but an up-to-date and comprehensive appraisal of psoriasis guidelines is currently lacking. To close this gap, the researchers sought to appraise any clinical global clinical practice guideline published from 2015 to 2021 that covered the treatment, prevention, and diagnosis of psoriasis.

A total of 3 tools were used to perform critical appraisal of the guidelines: the previously validated AGREE II instrument, Lenzer’s red flags, and the IOM criteria of trustworthiness.

The researchers explained that the AGREE II tool evaluates a guideline across 6 domains, including scope and purpose, stakeholder involvement, rigor of development, clarity of presentation, applicability, and editorial independence. The investigators used a modified green, yellow, and red traffic light rating system to present the tool’s results of quality assessment. Each domain was classified as green for excellent quality (score ≥70%), yellow for average quality (score ≥50% and <70%), and red for poor quality (score <50%).

In addition, the researchers stated that the Lenzer’s red flags assessment tool examines guidelines across 8 domains, including sponsorship of professional society, direct industry sponsorship and funding, financial conflict of committee chair, financial conflict of panel members, committee stacking, involvement of expert methodologist, external review, and inclusion of non-physician stakeholders. Ratings were marked with a “red flag” to indicate a risk of bias, “uncertain” to describe insufficient information to reach a conclusion, or “no issue” if there is no detected risk of bias.

The IOM’s criteria of trustworthiness also evaluated the guidelines across 8 domains, including establishing transparency, management of conflict of interest, guideline development group composition, clinical practice guideline–systematic review intersection, establishing evidence foundations for and rating strength of recommendations, articulation of recommendations, external review, and updating procedures. Results were presented as either “fully met,” “partially met,” or “not addressed.” Guidelines that had a higher number of “fully met” areas were considered as having higher trustworthiness. In contrast, guidelines with higher areas of “not addressed” were considered to have lower levels of trustworthiness.


In total, the researchers identified and included 33 psoriasis clinical practice guidelines in the descriptive analysis and critical appraisal. Most guidelines were from the United States (n=12) and Europe (n=12), with the remaining guidelines from the United Kingdom (n=5), Brazil and Latin America (n=2), Canada (n=1), and Japan (n=1).

The AGREE II appraisal showed that most guidelines were assessed highly in scope and purpose as well as clarity of presentation. Stakeholder involvement, rigor of development, and applicability were the 3 domains most frequently associated with lower quality.

There were only 5 guidelines appraised as having “excellent quality” across the 6 AGREE II domains. These included the British Association of Dermatologists

(BAD) guidelines for biologic therapy for psoriasis 2020: a rapid update, Frenchguidelines on the use of systemic treatments for moderate to severe psoriasis in adults, S3 Guideline for the treatment of psoriasis vulgaris, update – short version parts 1 and 2, NICE Psoriasis: assessment and management (CG153), and EuroGuiDerm guideline on the systemic treatment of psoriasis vulgaris – parts 1 and 2.

A total of 22 clinical practice guidelines raised 1 or more of Lenzer’s red flags, and 9 clinical practice guidelines raised 3 or more red flags. These findings indicated potential bias in these guideline statements.

The 2 areas that had the most “fully met” criteria for higher trustworthiness by IOM’s criteria standards were articulation of recommendations (73%) and establishing evidence foundations and rating strength of recommendations (67%). In contrast, the 2 areas with the most “not addressed” criteria included external review (58%) and updating procedures (39%). Based on the IOM’s criteria, only 3 guidelines scored 7 or higher for the “fully met” criteria and consequently demonstrated the highest level of trustworthiness. These guidelines included the NICE Psoriasis: assessment and management (CG153), BAD guidelines for biologic therapy for psoriasis 2020: a rapid update, and EuroGuiDerm guideline on the systemic treatment of psoriasis vulgaris – parts 1 and 2.

In addition, the researchers noted that the EuroGuiDerm guideline represented the only psoriasis clinical practice guidance that consistently demonstrated high quality across all 3 appraisal tools. The EuroGuiDerm guideline received “excellent quality” across the 6 AGREE II domains, no Lenzer’s red flags, and high levels of trustworthiness based on the IOM criteria.


Based on their research, the investigators concluded that there exist 5 areas that require improvement for future guidelines on psoriasis: stakeholder involvement, rigor of development, applicability, proper external review, and clear guideline updating procedures. The investigators added that there also exists a need for an “explicit process for updating” clinical practice guidelines, given that these evidence-based guidance documents serve “to reflect updated standards of care in an era of accelerated research dissemination.”

The researchers noted that limitations of their review included the possibility that some psoriasis guidelines were missed in the systemic search, particularly guidelines not written in English, as well as the lack of formal training tools for Lenzer’s red flags and IOM’s criteria of trustworthiness.

Despite these limitations, the researchers recommend that “critical appraisal tools be utilized during the CPG development process to guide the creation of high-quality, rigorous, and trustworthy guidelines.”


Yen H, Huang CH, Huang IH, et al. Systematic review and critical appraisal of psoriasis clinical practice guidelines: a Global Guidelines in Dermatology Mapping Project (GUIDEMAP)Br J Dermatol. Published online February 13, 2022. doi:10.1111/bjd.21047