In this study, various health care professionals will follow an E-learning module in which BCC detection on OCT is explained. Thereafter, the participants will test their skill by assessing OCT-scans. Their performance will be monitored using cumulative-sum analysis. After completion, newly trained OCT assessors will test their diagnostic accuracy for BCC detection on OCT in a exploratory study. The trainability, amount of required training and diagnostic accuracy will be compared between dermatologist and non-dermatologists.

Accurate detection of BCC on OCT requires substantial training and for future implementation of OCT, many OCT assessors need to be trained. Cumulative-sum analysis (CUSUM-analysis) can be used to objectify the competence of OCT assessors and has been previously used to monitor the competence of OCT assessors. Hence CUSUM-analysis may be valuable in training new assessors. A consensus statement from 2021 states that OCT scans should be acquired and interpreted by dermatologists. But this consensus is challenged by various studies in which OCT assessors were non-dermatologists. All non-dermatologist OCT assessors achieved high diagnostic accuracy. In addition, as diagnosis, treatment and follow-up of BCC patients constitute a substantial proportion of the workload of dermatologists, the question arises whether the acquisition of OCT scans and the subsequent assessment thereof could be outsourced to non-dermatologists. This could reduce the workload of the dermatologist, shorten waiting lists and potentially reduce costs.

In an E-learning dermatologists and non-dermatologists will learn about BCC features on OCT as described by Hussain et al. In this E-learning they will learn how to systematically examine an OCT-scan and detect BCC features. They will also be informed on common pitfalls in BCC detection. Thereafter they will start a CUSUM-module containing 400 OCT-scans (50% BCC vs. 50% non-BCC) to monitor cumulative successes and failures in diagnostic assessments. The competence of OCT assessors can be objectified using preset acceptable (16%) and unacceptable error rates (25%). The error rate is defined as the sum of false negative and false positive diagnoses divided by the total number of assessed OCT scans. For all OCT scans, the histologically verified diagnosis based on punch or excision biopsy is available. The OCT assessor will practice until an acceptable performance rate is achieved and maintained (over 50 scans). A secondary objective will be to explore the diagnostic accuracy in terms of sensitivity and specificity. Once an acceptable performance rate is achieved and maintained, assessors will assess a new cohort of 100 OCT scans (50% BCC and 50% non-BCC). Their level of suspicion for BCC will be expressed on a 5-point Likert-Scale. Diagnostic parameters will be compared between dermatologists and non-dermatologists.

Inclusion Criteria:

• Health care provider or medical student

Exclusion Criteria:

• Previous experience with OCT

The study population will consist of various health care provides; dermatologists, residents/clinical researchers, nurses and medical students. We aim to include at least 5 participants per category of healthcare providers.

To be decided