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Psoriasis is a disease with the potential to be life ruining.
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To justify health expenditure on its management, it is vital to be able to show that interventions make a difference to a patient’s skin disease and ability to function normally.
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With modern methods of validating health care measurement instruments, more appropriate tools are being developed for use in clinical trials and routine clinical practice.
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The place of long-established tools is examined in the light of new tools that have
Assessing Psoriasis Severity and Outcomes for Clinical Trials and Routine Clinical Practice
Section snippets
Key points
Assessment and outcomes
Historically, dermatologists and others looking after patients with psoriasis have tended to record response to treatment, if at all, with rather imprecise phrases such as “nearly clear,” “a bit better,” “slightly improved,” “worse,” or “flared up.” This probably still holds true for the majority of consultations between psoriasis patients and health care professionals. If they have instituted a new therapy, there is almost certainly a tendency for them to write “slightly better” rather than
Psoriasis assessment tools: a historical perspective
For the current generation of dermatologists brought up to consider randomized, controlled trials as the norm for investigating new therapies for skin disease, it is instructive to look back a few decades. Until the advent of potent topical corticosteroids in the late 1950s, very few comparative trials in the field of psoriasis were conducted. The mainstays of treatment up until then had been tar, anthralin (dithranol), and broadband UVB phototherapy. At that time, there was no accepted
The dimensions of psoriasis
Psoriasis is a complex disease, is often lifelong, and, in severe cases, life ruining. There is much more to it than its outwardly visible manifestations. This has recently been neatly summarized in the UK’s NICE Guidance on the assessment and management of psoriasis17:
Death directly due to psoriasis is rare, but the chronic, incurable nature of psoriasis means that associated morbidity is significant. People with psoriasis, like those with other major medical disorders, have reduced levels of
Desiderata for psoriasis assessment and outcome measures
When PASI was born, its creators had very little guidance on how to go about the task. PASI was then adopted with rather little critical thought about its suitability for the tasks it was expected to perform. Since that time, there have been considerable advances in developing and evaluating assessment tools.
It is important to recognize that it is impossible to produce a “one size fits all” measure for assessing all aspects of psoriasis. The requirements for a proof-of-concept study of a new
Instruments for observer-rated assessment of psoriasis severity
A large number of scoring systems for psoriasis have been devised, the majority of which can be classed as “objective” in the sense that the assessment is performed by someone other than the patient (observer-rated). The most well-known of these is the PASI.
Instruments for self-assessment of psoriasis severity by patients
Despite focus in recent years on patient-reported assessments, there has been surprisingly little attempt to develop these for psoriasis.
Instruments for assessing the psychosocial impact of psoriasis
These instruments have been systematically reviewed.47 Eight scales were found to perform satisfactorily in terms of validity, reliability, sensitivity to change (responsiveness), and acceptability. By far the most widely used in psoriasis trials are the DLQI29 and SF-36.26 The other scales that were approved have been used much less frequently and included Skindex 29, Skindex 17, Dermatology Quality of life Scale PDI,29 Impact of Psoriasis Questionnaire, and Psoriasis Index of Quality of Life.
Composite instruments for the assessment of psoriasis
In the field of rheumatology, a large number of composite assessment scores have been developed to assist in defining response to interventions. For example, the American College of Rheumatologists/European League Against Rheumatism Core Data Set for rheumatoid arthritis studies includes 3 assessor-derived measures—tender joint count, swollen joint count, and PGA; 1 laboratory test—erythrocyte sedimentation rate or C-reactive protein level; and 3 patient self-reported questionnaires—on
Outcome measures for psoriasis
Outcome measures involve either assessing the magnitude of change or the attainment of a particular goal, which in the case of psoriasis would normally be clearance or near clearance. There is a presumption that psoriasis was present when the intervention was instituted. It would be rare, however, for some measure of psoriasis severity not to have been recorded at enrollment into an interventional study for psoriasis.
Summary
The advent of powerful new agents for treating psoriasis has put a spotlight on the need for reliable and practical tools for assessing psoriasis and its impact. Further work is still needed to validate existing instruments and to develop new ones, with the hope that PASI will no longer remain the mainstay of psoriasis severity assessment. The International Psoriasis Council recognizes the need for change and will continue to work to improve the tools at our disposal.
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2023, Biomedical Signal Processing and ControlCitation Excerpt :Therefore, psoriasis is one of the chief concerns for health care organizations and society [17,18]. The estimation of the total skin surface area affected by psoriasis is an important indicator for the dermatologist during psoriasis treatment [20]. Therefore, the segmentation of psoriasis lesions from the healthy skin region is the primary step.
Translation into Spanish and field-testing of a new score for evaluating psoriasis severity: The Simplified Psoriasis Index (SPI)
2022, Actas Dermo-Sifiliograficas
Funding Sources: None.
Conflict of Interest: Dr R.J.G. Chalmers has been involved in the development of the Simplified Psoriasis Index, but has no financial interests in this or in other matters relating to psoriasis.