Table 2

 Variables collected that describe the patients’ health status, treatment, and environment

IV infusion control deviceAn automated volumetric infusion device that provides an accurate infusion of IV fluids at a rate and volume determined by the clinician. The converse would be a controlled regulator giving set which is non-automated and requires manual adjustment of a regulator clamp to ensure correct flow rate.
IV linesPeripheral, peripherally inserted central catheter (PICC), or central lines.
Non-IV linesNasogastric tubes and drainage tubes such as urinary catheters and wound drainage tubes.
AdditiveAny electrolyte added to the bag of IV fluid.
Alternating bags of fluidRefers to two different types of prescribed IV fluids to be administered in an alternating sequence.
BuretteAn optional piece of IV equipment that is placed between the IV bag and IV administration set, which is used to control the amount of fluid available to be infused.
Invasive proceduresIncludes surgery or endoscopy, whereas non-invasive procedures would include admission for observation or IV antibiotics.
All permanent staffIndicates that all nurses working at the time of the observation were permanently allocated to a specific ward. The converse would be a mixture of permanent and pooled staff where pooled nurses work on different wards on different days
Creatinine clearanceEstimated glomerular filtration rate using the Cockcroft-Gault equation, where total body weight was used as the weight descriptor.
Duration of infusionLength of time from initiation of administration to the time the observation was made.
Time of dayTime that the observation was made. This was treated as a binomial variable consisting of either the day shift (09.00 to 16.00 hours) or the night shift (20.00 to 03.00 hours).
IV pain reliefIV infusions of opiates.
Level of nursing experienceAverage score of all nurses working at the time the observation was made based on their grade. Graduate nurses, enrolled nurses, and re-entry nurses were given a score of 10, level 1 nurses were given a score of 20, and level 2 nurses were given a score of 30.
Occupancy of bed bayNumber of occupied beds within the bed bay divided by the maximum number of beds within the bed bay.