Quality assurance of paediatric lateral chest radiographs

Lateral chest radiographs aid in paediatric clinical practice in countries where the diagnosis of primary pulmonary tuberculosis (PTB) still relies heavily on the chest radiograph. This study aimed to create a validated quality assurance (QA) tool investigating the diagnostic performance of this projection by applying this to a database of lateral chest radiographs in children with suspected PTB.

The QA tool was built to include a compilation of criteria from the different sources, accompanied by graphic representations and objective measurements where appropriate. Each defined criterion (radiographic error) was evaluated by implementing the QA tool on 300 radiographs, scored by three readers. The sample was subjected to two separate sets of data analysis, based on averages, and on majority decision methodology.

The QA tool was based on existing published criteria, as well as under-collimation and under-inspiration, two de novo criteria. For the total 900 reads, errors were categorized as patient-related in 681 (75.7%) and radiographer-related in 421 (46.8%) and 122 (13.6%) had no errors. The average number of errors per radiograph ranged from 0.9 to 4.7 errors out of the 11 quality factors reviewed. When considering the majority decision, the median errors per radiograph was 1 (IQR 1-2) (range 0-5). Inter-rater agreement varied for different criteria.

A novel QA tool for evaluating lateral chest radiographs was developed which requires further efforts of refinement regarding criteria such as exposure, field of view: under-collimation, and motion artifact, which remain subjective. The designed QA tool will allow comparison of radiograph quality before and after interventions. Furthermore, the tool can be used in tackling childhood PTB in low- and middle-income countries (LMICs) since the hallmark of the disease is lymphadenopathy, which is often depicted best on lateral chest radiographs.