BACKGROUND: Clinical lung ultrasound examinations are widely used in the primary assessment or monitoring of patients with dyspnoea or respiratory failure. Despite being increasingly implemented, there is no international consensus on education, assessment of competencies, and certification. Today, training is usually based on the concept of mastery learning, but is often unstructured and limited by bustle in a clinical daily life. The aim of the systematic review is to provide an overview of published learning studies in clinical lung ultrasound, and to collect evidence for future recommendations in lung ultrasound education and certification.

METHODS: According to PRISMA guidelines, three databases (PubMed, Embase, Cochrane Library) were searched, and two reviewers examined the results for eligibility. Included publications were described and assessed for level of evidence and risk of bias according to guidelines from Oxford Centre for Evidence-Based Medicine and Cochrane Collaboration Tool for Risk of Bias assessment.

RESULTS: Of 7796 studies screened, 16 studies were included. Twelve pre- and post-test studies, three descriptive studies and one randomized controlled trial were identified. Seven studies included web-based or online modalities, while remaining used didactic or classroom-based lectures. Twelve (75%) studies provided hands-on sessions, and of these, 11 assessed participants' hands-on skills. None of the studies used validated neither written nor practical assessment. The highest level of evidence score was 2 (n = 1), remaining scored 4 (n = 15). Risk of bias was assessed high in 11 of 16 studies (68.75%).

CONCLUSION: All educational methods proved increased theoretical and practical knowledge obtained at the ultrasound courses, but the included studies were substantial heterogeneous in setup, learning-, and assessment methods, and outcome measures. On behalf of current published studies, it was not possible to construct clear guidelines for the future education and certification in clinical lung ultrasound, but the use of different hands-on training facilities tends to contribute to different aspects of the learning process. This systematic review proves a lack of learning studies within this content, and research with validated theoretical and practical tests for assessment is desired.