Objectives To compare low contrast detail (LCD) detectability and radiation dose for routine paediatric chest X-ray (CXR) imaging protocols among various hospitals. Methods CDRAD 2.0 phantom and medical grade polymethyl methacrylate (PMMA) slabs were used to simulate the chest region of four different paediatric age groups. Radiographic acquisitions were undertaken on 17 X-ray machines located in eight hospitals using their existing CXR protocols. LCD detectability represented by image quality figure inverse (IQFinv) was measured physically using the CDRAD analyser software. Incident air kerma (IAK) measurements were obtained using a solid-state dosimeter. Results The range of IQFinv, between and within the hospitals, was 1.40–4.44 and 1.52–2.18, respectively for neonates; 0.96–4.73 and 2.33–4.73 for a 1-year old; 0.87–1.81 and 0.98–1.46 for a 5-year old and 0.90–2.39 and 1.27–2.39 for a 10 … View article