A core outcome domain set for clinical research on capillary malformations (the COSCAM project): an e-Delphi process and consensus meeting

BACKGROUND

There is limited evidence on the best available treatment options for capillary malformations (CMs), mainly due to the absence of uniform outcome measures in trials on therapies. A core outcome set (COS) enables standard reporting of trial outcomes, which facilitates comparison of treatment results.

OBJECTIVES

To develop a core outcome domain set (CDS), as part of a core outcome set (COS), for clinical research on CMs.

METHODS

Sixty-seven potentially relevant outcome subdomains were recognized based on the literature, focus group sessions, and input from the COSCAM working group. These outcome subdomains were presented in an online Delphi study to CM experts (medical specialists and authors of relevant literature) and (parents of) patients with CM (international patient associations). During three e-Delphi study rounds, the participants repeatedly scored the importance of these outcome subdomains on a seven-point Likert scale. Participants could also propose other relevant outcome subdomains. Consensus was defined as ≥ 80% agreement as to the importance of an outcome subdomain among both stakeholder groups. The CDS was finalized during an online consensus meeting.

RESULTS

In total 269 participants from 45 countries participated in the first e-Delphi study round. Of these, 106 were CM experts from 32 countries, made up predominantly of dermatologists (59%) and plastic surgeons (18%). Moreover, 163 (parents of) patients with CM from 28 countries participated, of whom 58% had Sturge-Weber syndrome. During the two subsequent e-Delphi study rounds, 189 and 148 participants participated, respectively. After the entire consensus process, consensus was reached on 11 outcome subdomains: colour/redness, thickness, noticeability, distortion of anatomical structures, glaucoma, overall health-related quality of life, emotional functioning, social functioning, tolerability of intervention, patient satisfaction with treatment results, and recurrence.

CONCLUSIONS

We recommend the CDS to be used as a minimum reporting standard in all future trials of CM therapy. Our next step will be to select suitable outcome measurement instruments to score the core outcome subdomains. What is already known about this topic? Besides physical and functional sequelae, capillary malformations (CMs) often cause emotional and social burden. The lack of uniform outcome measures obstructs proper evaluation and comparison of treatment strategies. As a result, there is limited evidence on the best available treatment options. The development of a core outcome set (COS) may improve standardized reporting of trial outcomes. What does this study add? A core outcome domain set (CDS), as part of a COS, was developed for clinical research on CMs. International consensus was reached on the recommended core outcome subdomains to be measured in CM trials: colour/redness, thickness, noticeability, distortion of anatomical structures, glaucoma, overall health-related quality of life, emotional functioning, social functioning, tolerability of intervention, patient satisfaction with treatment results, and recurrence. This CDS enables the next step in the development of a COS, namely to reach consensus on the core outcome measurement instruments to score the core outcome subdomains. What are the clinical implications of this work? The obtained CDS will facilitate standardized reporting of treatment outcomes, thereby enabling proper comparison of treatment results. This comparison is likely to provide more reliable information for patients about the best available treatment options.

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

Background

Due 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.

Methods

The 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.

Results

A 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 (n = 13) in focus group sessions and 38 were suggested by the experts of the COSCAM‐founding group. Seven were excluded because of overlap.

Conclusion

The 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.

A systematic review of outcome reporting in laser treatments for dermatological diseases

The standardization of outcome reporting is crucial for interpretation and comparison of studies related to laser treatment of skin disorders. In collaboration with the Cochrane Skin-Core Outcome Set Initiative (CS-COUSIN), a procedure has been proposed to find consensus on the most important generic outcome domains (what to measure) for implementation in the international Laser TrEAtment in Dermatology (LEAD) registry. As the first step in the development of a generic outcome set for the LEAD registry, we undertook a systematic review to identify outcomes, outcome measurement instruments, methods and definitions reported in recently published literature of laser treatments for skin disorders. A systematic search was conducted and generated a total of 707 papers. We assessed 150 studies including all types of studies involving laser treatments for the skin. Two researchers independently extracted the type, definition and frequency of all outcomes and used outcome measurement instruments. We identified 105 verbatim outcomes that were categorized into eight domains recommended by the COMET framework: appearance, long-term effects, physician and patient-reported physical signs, satisfaction, health-related quality of life, psychological functioning and adverse events. Heterogeneity in outcome reporting (e.g. categories and outcome measurement instruments) was high, and definitions were insufficiently reported. There was a clear under representation of life impact domains, including satisfaction (23%) quality of life (3%) and psychological functioning (1%). Outcome reporting concerning laser treatments for the skin is heterogeneous. Standardized outcomes are needed for improving evidence synthesis. Results of this review will be used in the next step to reach consensus between stakeholders on the outcome domains to be implemented in the LEAD registry.

Incremental build-up food challenge--a new diagnostic approach to evaluate pseudoallergic reactions in chronic urticaria: a pilot study: stepwise food challenge in chronic urticaria

BACKGROUND

The remission rate of patients with chronic urticaria (CU) due to elimination diets varies between 31% and 71%. However, the diagnostic value of subsequent traditional oral provocation tests with food additives in capsules remains unsatisfactory.

OBJECTIVES

A newly incremental build-up food challenge (IBUF) for patients with CU was designed and implemented in an open pilot study. Primary endpoint was the percentage of patients developing urticaria during at least one step of IBUF after an initial complete remission due to a pseudoallergen-free elimination diet.

METHODS

In total, 153 patients with CU were submitted for 5 weeks to a pseudoallergen-free diet. All patients with remission were included to the 6-week IBUF protocol, containing pseudoallergen-rich foods in a systematic and additive manner. The recurrence and severity of CU was evaluated by urticaria score. Subjective disturbance and quality of life were evaluated by patients' diary, visual analogue scale and quality of life questionnaire (CU-Q2oL). Subsequently, patients were followed up for 3-24 months after IBUF by a telephone interview.

RESULTS

A total of 104 patients completed the pseudoallergen-free diet, whereby 51% reported partial, 17% complete and 32% no remission due to the diet. All diet responders showed a decrease in subjective impairment, urticaria and quality of life score (P<0.001 each). Eighty-six percent (12/14) of the patients reaching complete remission, showed a recurrence of urticaria symptoms during the IBUF protocol. Fifty-eight percent (7/12) of these patients still remained free of symptoms due to avoidance of IBUF-identified foods at telephone follow-up. In patients with partial remission to pseudoallergen-free diet, however, IBUF did not provide information about the cause of urticaria symptoms.

CONCLUSIONS

The newly developed IBUF protocol seemed to be a promising method for identifying individually incompatible foods in some CU patients. IBUF should be verified by randomized controlled trials to gain additional evidence for its diagnostic value.

A phantom for diffusion-weighted imaging of acute stroke

A tissue phantom for diffusion-weighted imaging was developed, basing its contrast between two compartments on different apparent diffusion coefficients, without contrast due to T2 relaxation and proton density. These contrast properties of the phantom simulate the situation found in normal gray matter and areas of acute ischemia. A possible application of the phantom was demonstrated for the investigation of the accuracy of volume measurements based on diffusion-weighted images.

[Diffusion-weighted imaging in acute stroke]

Magnetic resonance imaging represents today the most important tool in neuroradiology for both clinical practice and research. MRI allows imaging of the human body in 2 or 3 dimensions with variable tissue contrast. The natural diffusion of tissue protons can now be used as a supplementary contrast mechanism. Different MRI techniques can be used to obtain clinically useful diffusion-weighted images. These techniques all require the use of strong gradient pulses in order to obtain the diffusion contrast. In the current article, the most important physical principles of diffusion measurement are presented. After a short introduction into the basic physical principles, we will present the prerequisites and limitations of clinically relevant applications today. Finally a few select examples of clinical use of these techniques in the acute diagnosis of stroke will be presented.

Clinical experience with diffusion-weighted MR in patients with acute stroke

PURPOSE

Our purpose was to evaluate the clinical efficacy, sensitivity, and specificity of echo-planar diffusion-weighted MR imaging in patients with acute infarction.

METHODS

We retrospectively analyzed 194 cases of acute ischemic stroke diagnosed clinically within 24 hours of onset and studied with echo-planar diffusion-weighted MR imaging. Examinations were considered to be positive for infarction when an increase in signal was noted on images acquired at a high b value but absent on images with a low b value. A final clinical diagnosis of acute stroke was used as the standard of reference. A subset of 48 patients scanned within 6 hours was also analyzed.

RESULTS

Diffusion-weighted MR imaging studies were positive in 133 of 151 cases of infarction (88% sensitivity) and negative in 41 of 43 cases with no infarction (95% specificity). Two cases identified as positive on diffusion-weighted images had nonischemic diagnoses (1.5% false-positive rate). Diffusion-weighted imaging had a positive predictive value of 98.5% and a negative predictive value of 69.5%. Use of T2-weighted sequences as well as diffusion-weighted imaging produced no false-positive findings. Of the negative scans, 69.5% corresponded to transient ischemic attacks or infarcts (mostly small brain stem infarcts). When only cases scanned within 6 hours of onset were considered, the sensitivity rose to 94% and the specificity to 100%.

CONCLUSION

Despite bias due to dependence between diffusion-weighted imaging and the final diagnosis, this analysis suggests high sensitivity and specificity for echo-planar diffusion-weighted imaging in the diagnosis of acute cerebral infarction, although negative scans did not rule out an ischemic pathogenesis.