Development and evaluation of the IMPACT programme patient resources to increase understanding of psoriasis and its management: a mixed-methods feasibility study

Psoriasis is a complex skin condition associated with comorbidities, unhealthy lifestyle behaviours and psychological distress. Patients’ understanding of psoriasis is low and self-management is often challenging. The Common-Sense Self-Regulatory Model (CS-SRM) of Health and Illness emphasizes the role an individual’s illness/treatment beliefs play in coping and self-management. A set of new patient resources (Pso Well�; Psoriasis and Wellbeing) informed by the CS-SRM addressed psoriasis as a long-term condition, along with medication management and lifestyle behaviours. This study investigated whether these resources (i) can broaden understanding of psoriasis and its comorbidities without increasing anxiety; (ii) are acceptable/ usable; and (iii) help patients to identify putative mechanisms of change following exposure to specific content. Pso Well� patient resources were designed in iterative phases by theorymapping concepts to components of the CS-SRM and modifying content/design following extensive collaboration with clinicians and patients. Resources were evaluated in a primary-care-based cohort of patients with psoriasis. Psoriasis severity was assessed with the Simplified Psoriasis Index (SPI-s) at baseline. The Revised Illness Perceptions Questionnaire (IPQ-R modified for psoriasis) and the Hospital Anxiety and Depression Scale (HADS) were administered pre- and postexposure to the new resources. Visual analogue scales (VASs) assessed patients’ perceptions of change in understanding and anxiety. In-depth qualitative interviews using principles of framework analysis with a purposively sampled subset of participants explored the acceptability, usability and perceived active ingredients of the resources. Fifty-five patients completed the pre- and postintervention questionnaires (56% female; mean age 58 years; SPI-s severity: 87% mild, 9% moderate, 4% severe). Postexposure, a large effect size was indicated in two domains of the IPQ-R: illness coherence [t(55) = �3�48, P < 0�01 (two-tailed), eta2 = 0�19) and personal control [t(55) = �2�98, P < 0�01 (two-tailed), eta2 = 0�14]; and a medium effect size in one domain: treatment control [t(55) = �2�08, P = 0�04 (twotailed), eta2 = 0�08]. Neither anxiety nor depression scores increased for HADS. For VAS scores, 80% of participants reported that their understanding of psoriasis had increased and 16% reported feeling less anxious. Interviews with 19 patients indicated that the new resources were acceptable and usable. Components of the materials perceived to promote change were relevance of content, coherent linking of disease aspects, trustworthiness, design values and ease of reading. This feasibility study suggests that carefully designed, theory-based, written psoriasis resources are acceptable to patients and can improve understanding, coherence and sense of control of their disease without corresponding increases in anxiety.