Table 2 Inclusion and exclusion criteria

Empirical study

Published before 2010

Value of radiological examination

Patient case report, letter, comment, editorial, guidelines

Identifying low-value/inappropriate diagnostic imaging (radiology)

Mass-screening related studies

Extent/use of low-value diagnostic imaging (radiology)

Dental imaging, optical imaging, thermal imaging, microscopic imaging

RCT, non-randomized controlled trial, cohort study, descriptive study, case studies, mixed-methods, multi-methods

Animal studies, studies on cells/tissue

Studies comparing two or more imaging procedures

Studies where imaging is shown to avoid other inappropriate medical procedures/treatments

English, German, Dutch, Danish, Swedish, or Norwegian language

Image quality evaluation/improvement projects

Interventions to reduce low-value imaging