Validity of the PBI-TOP tool for assessing patient goals and benefits of topical treatment in psoriasis

Topical treatment is often used as a first-line therapy for mild-to-moderate psoriasis and is available as cream, ointment, gel, foam, and lotion.¹ Topical treatment works by reducing inflammation and reducing skin cell growth, but it can be less effective in patients with severe symptoms.¹ Additionally, topical treatment can require increased effort and time to apply, which may result in low adherence.¹

Here, we summarize a pilot validation study by Blome et al.¹ published in British Journal of Dermatology assessing the feasibility of the Patient Benefit Index for Topical Treatment (PBI-TOP) tool in measuring the benefits of topical treatment in adult patients with psoriasis.¹

Study design¹

• The following themes were identified through patient focus groups, patient interviews, open surveys, and literature searches:

• • Benefit of treatment
    • Effectiveness on symptoms
    • Effectiveness on quality of life
  • Characteristics of the preparation

• Based on these themes, a pilot version of PBI-TOP was created, consisting of two sections:
  • Patient needs questionnaire (PNQ), where patients rate the importance of treatment goals in current/upcoming treatment
  • Patient benefit questionnaire (PBQ), where patient rate whether treatment goals have been achieved
• Using both sections, a weighted score is calculated that shows treatment benefit for the patient.

Key findings¹

• A total of 154 patients completed the PNQ.
  • Of these, 121 also completed the PBQ and were included in treatment goal and benefit analysis in addition to assessing pilot validity.
• Achievement of items, as assessed by PBQ, with the highest mean importance in the therapy goals and characteristics preferences in PNQ are shown in Figure 1. The percentage of patients who agreed they were quite/very important, were:
  • Less dry, cracked or scaly skin (86.8%)
  • Reduced redness or inflammation of the skin (86.0%)
  • No visible skin changes (78.5%)
  • No more itching (80.2%)
• In the preparation characteristics preferences section of PBI-TOP, items with the highest mean importance in the PNQ, and percentage of patients who agreed they were quite/very important, were:
  • The preparation should be well tolerated (83.5%)
  • The preparation should not stain objects (71.9%)
  • The preparation should be easy to use (71.9%)
  • The preparation should be easy to dose (68.6%)
• Items with the highest importance in the PNQ were not always highly achieved according to the PBQ (Figure 1). For example, ~60% or less of patients agreed that their therapy goals were quite or very much achieved after use of topical therapy, despite ~80% stating that this was quite/very important.

PBQ, patient benefit questionnaire.
*Data from Blome, et al.¹

 

• Table 1 shows the internal consistency of PBI-TOP scale and its correlation with convergent criteria.

Table 1. PBI-TOP scale internal consistency and correlation with convergent criteria*

BSA, body surface area; DLQI, Dermatology Life Quality Index; PASI, Psoriasis Area and Severity Index; PNQ, patient needs questionnaire; PBI-TOP, Patient Benefit Index, version for topical treatment; PBQ, patient benefit questionnaire; r, correlation coefficient. *Data from Blome, et al.1 †Values in bold are statistically significant.
PBI-TOP scale	Internal consistency (Patients with PNQ data, n = 154)	Correlation with convergent criteria (patients with PNQ and PBQ data, n = 121)
	Cronbach’s α	DLQI r (p value)†	PASI r (p value)†	BSA r (p value)†
Overall effectiveness score	0.94	–0.41 (<0.001)	–0.32 (0.001)	–0.22 (0.046)
Effectiveness subscale
Symptoms	0.90	–0.41 (<0.001)	–0.27 (0.007)	–0.16 (0.155)
Quality of life	0.94	–0.32 (0.002)	–0.33 (0.002)	–0.23 (0.055)
Characteristics of the preparation score	0.90	–0.34 (0.001)	–0.19 (0.053)	–0.19 (0.089)

 

Key learnings

The PBI-TOP tool demonstrated feasibility for use in patients with plaque psoriasis. It can assist in personalizing topical treatment in patients with psoriasis, improving treatment adherence and outcomes. The findings are limited by lack of patients with severe psoriasis and diverse patient groups; therefore, further research to address the applicability of PBI-TOP to other patients groups is warranted. A long-term longitudinal study is ongoing to confirm the consistency and validity of PBI-TOP.