Factors associated with insufficient nasogastric tube visibility on X-ray: a retrospective analysis.

• The quality of chest X-rays to confirm the positioning of nasogastric tubes in adults can be improved considerably. • There are several factors influencing the confirmation of nasogastric tube positioning on X-ray. • Defining patient profiles at risk for an insufficient visibility of the tube on X-ray will indirectly contribute to an improvement of the chest X-ray quality.