Assessment of Advanced Diagnostic Bronchoscopy Outcomes for Peripheral Lung Lesions: A Delphi Consensus Definition of Diagnostic Yield and Recommendations for Patient-centered Study Designs. An Official American Thoracic Society/American College of Chest Physicians Research Statement

Abstract

Background: Advanced diagnostic bronchoscopy targeting the lung periphery has developed at an accelerated pace over the last two decades, whereas evidence to support introduction of innovative technologies has been variable and deficient. A major gap relates to variable reporting of diagnostic yield, in addition to limited comparative studies. Objectives: To develop a research framework to standardize the evaluation of advanced diagnostic bronchoscopy techniques for peripheral lung lesions. Specifically, we aimed for consensus on a robust definition of diagnostic yield, and we propose potential study designs at various stages of technology development. Methods: Panel members were selected for their diverse expertise. Workgroup meetings were conducted in virtual or hybrid format. The cochairs subsequently developed summary statements, with voting proceeding according to a modified Delphi process. The statement was cosponsored by the American Thoracic Society and the American College of Chest Physicians. Results: Consensus was reached on 15 statements on the definition of diagnostic outcomes and study designs. A strict definition of diagnostic yield should be used, and studies should be reported according to the STARD (Standards for Reporting Diagnostic Accuracy Studies) guidelines. Clinical or radiographic follow-up may be incorporated into the reference standard definition but should not be used to calculate diagnostic yield from the procedural encounter. Methodologically robust comparative studies, with incorporation of patient-reported outcomes, are needed to adequately assess and validate minimally invasive diagnostic technologies targeting the lung periphery. Conclusions: This American Thoracic Society/American College of Chest Physicians statement aims to provide a research framework that allows greater standardization of device validation efforts through clearly defined diagnostic outcomes and robust study designs. High-quality studies, both industry and publicly funded, can support subsequent health economic analyses and guide implementation decisions in various healthcare settings.

Keywords: advanced diagnostic bronchoscopy; diagnostic accuracy; diagnostic yield; lung cancer; pulmonary nodule.

Figure 1.

Standards for Reporting Diagnostic Accuracy Studies-inspired flow diagram, adapted for studies of minimally invasive diagnostic procedures for peripheral pulmonary nodules (36, 37). Diagnostic yield is calculated as the sum of “specific diagnosis: malignant” and “specific diagnosis: benign” (in the numerator), divided by “procedures performed” (in the denominator). The remaining risk of malignancy in those without a specific diagnosis is subsequently calculated as the sum of procedures with a “final diagnosis: malignant” in those with a “nondiagnostic” result (in the numerator), divided by the sum of patients with a “reference standard available” in the “nondiagnostic” result group (in the denominator). The reference standard in many cases is clinicoradiological follow-up.

Figure 2.

Algorithmic approach to classifying peripheral lung biopsy results.