Development of a core outcome domain set for clinical research on capillary malformations (the COSCAM project)

Author(s): Langbroek, GB; Wolkerstorfer, A; Horbach, SER; Spuls, PI; Kelly, KM; Robertson, SJ; van Raath, MI; Al-Niaimi, F; Kono, T; Boixeda, P; Laubach, HJ; Badawi, AM; Troilius Rubin, A; Haedersdal, M; Manuskiatti, W; van der Horst, CMAM; Ubbink, DT; COSCAM study group | Abstract: BackgroundDue to a large variety in treatment outcomes reported in therapeutic trials and lacking patient-relevant outcomes, it is hard to adequately compare and improve current therapies for patients with capillary malformations (CMs). The Core Outcome Set for Capillary Malformations (COSCAM) project aims to develop a core outcome set (COS) for use in future CM trials, in which we will first develop a core outcome (sub)domain set (CDS). Here, we describe the methods for the development of a CDS and present the results of the first development stage.MethodsThe COSCAM project is carried out according to the recommendations of the Cochrane Skin Core OUtcomes Set INitiative (CS-COUSIN) and the Core Outcome Measures in Effectiveness Trials (COMET) initiative. During the first stage, we identified all potentially relevant outcome subdomains based on a systematic review, two focus group sessions and input from patient representatives of Dutch patient organizations and the COSCAM-founding group. In stage two, we will present the subdomains in a three-round e-Delphi study and online consensus meeting, in which CM patients, parents/caregivers and CM experts worldwide rate the importance of the proposed subdomains, hereby finalizing the core outcome (sub)domains of the CDS.ResultsA total of 67 potential outcome subdomains were included; sixteen were previously used in the literature, 20 were proposed by Dutch patients and their parents/caregivers (nn=n13) in focus group sessions and 38 were suggested by the experts of the COSCAM-founding group. Seven were excluded because of overlap.ConclusionThe final CDS may serve as a minimum standard in future CM trials, thereby facilitating adequate comparison of treatment outcomes. After this CDS development, we will select appropriate outcome measurement instruments to measure the core outcome subdomains.