Description of study variables and their measurement for reporting (created by authors)
| Measure | Measurement process | Definition of variable | Tools used to measure | Results reported |
| Aim 1 | ||||
| Medication errors | Direct observation of nurses during programming medications. Assessing reports from the error reporting system in the safe time period of the study | Errors during the medication administration process: wrong time from expected medication delivery start and end, dose, rate of infusion | Observations entered using a documentation form | Percentage of infusions with errors of total observed infusions and reported medication errors |
| Interruptions | Direct observation for interruptions during medication administration | Any additional external events that occur with the nurse during their preparation or administration of medications or programming the IVSP | Observations entered using a documentation form | Number of interruptions observed, duration of delay if programming stopped due to interruption and percentage of interruptions for total observed infusions |
| DERS compliance | IVSP report servers and direct observation of nurses using the DERS while programming medications/IVs | —contains libraries of medications with preset rates and dosages for medications and limits for manual dosing | Peristaltic—Knowledge Portal Pneumatic— Report server Observations entered using a documentation form | Percent of total infusions from the report server using drug library for peristaltic—Used population of like-unit acuity classification for denominator Observation noted if DERS library was used for infusion or not. |
| Aim 2 | ||||
| Compliance with IVSP set-up | Direct observation during clinical practice with programming IVSP | Compliance with the instructions for use by the manufacturers for both IVSPs | Direct observation using the instructions for use guidelines and measuring tape | Mean measurements in inches for each parameter and percentage of adherence to all expected set-up actions. Numbers can be positive or negative, depending on the relationship to the correct level. |
| Programming workload | NASA-TLX survey completed on the peristaltic IVSP prior to training for pneumatic IVSP and for the pneumatic IVSP, after clinical use for 2 months | A raw, unweighted survey assessment of mental demand, physical demand, temporal demand, performance, effort and frustration on a 0–20 scale. | NASA-TLX a Validated tool to measure workload | Mean of the raw sum of the total scores for the NASA-TLX |
| Programming time | Direct observation and timing of IVSP programming | Timing started at pressing the first button required to start programming sequence ended when the start infusion button/option is pressed | The stopwatch function on the same smartphone throughout study and recorded on study form | Mean time in seconds by infusion type (primary and secondary) |
| Ease-of-use | Survey completed for the peristaltic IVSP prior to training for pneumatic IVSP and for the pneumatic IVSP, after use for 2 months after clinical use | 10-item Likert type survey with five responses from strongly agree to strongly disagree. Imputed scores can range from 0 to 100 and grade from A to F | Validated tool for usability: SUS | Mean of imputed scores of SUS following guidelines for tool use |
DERS, dose error reduction systems; IVSP, intravenous smart pump; NASA-TLX, National Aeronautics and Space Administration Task Load Index; SUS, System Usability Scale.