Table 1.

Application of the EULAR recommendations¹⁶ in the development of the PsAID

	EULAR recommendations	Application in PsAID
1	Participation of PRPs is strongly recommended for clinical research projects and for the development of recommendations and guidelines, and should be considered for all other research projects	Patient participation has been an essential feature of the project to ensure that the PRO truly reflects the perspective of patients with psoriatic arthritis
2	Participation of PRPs should be considered in all phases of the project to provide experiential knowledge, with the aim of improving the relevance, quality and validity of the research process	Patients with psoriatic arthritis were involved in every phase of the development and validation process. The contribution varied depending on their patient role
3	A minimum of two PRPs should be involved in each project	PRPs were proportionally represented, their number was similar to that of the physician-researchers
4	Identification of potential PRPs should be supported by a clear description of expected contributions	Potential candidates received a comprehensive invitation, explaining in detail what was expected from them
5	The selection process of PRPs should take into account communication skills, motivation and constructive assertiveness in a team setting	PRPs were selected by their treating physicians based on a set of criteria, among which were communication skills, English reading and speaking and ability to travel
6	The principal investigator must facilitate and encourage the contribution of PRPs, and consider their specific needs	Support was provided by premeeting update sessions for patients. Identification of domains took place in a homogeneous patient meeting to guarantee a safe environment. During team meetings patients were encouraged to take part in the discussions and were regularly asked for their opinion
7	The principal investigator must ensure that PRPs receive information and training appropriate to their roles	The steering group provided regular updates and produced patient information packs before every team meeting, including a glossary of terms
8	The contribution of PRPs to projects should be appropriately recognised, including coauthorship when eligible	All PRPs whose participation maintained throughout the project became coauthor of the scientific manuscript

EULAR, European League Against Rheumatism; PRO, patient-reported outcome; PRPs, patient research partners; PsAID, Psoriatic Arthritis Impact of Disease.