Geographic information software programs' accuracy for interfacility air transport distances and time.

Area of Science:

• Emergency Medicine
• Aerospace Logistics
• Geospatial Analysis

Background:

• Interfacility flight times (IFFTs) are crucial for helicopter emergency medical services (HEMS).
• Predictability of IFFTs and accuracy of geographical information system (GIS) software for estimation require evaluation.
• Variability in IFFTs impacts operational efficiency and patient care.

Purpose of the Study:

• To assess the consistency and predictability of interfacility flight times (IFFTs).
• To evaluate the accuracy of geographical information system (GIS) software in estimating IFFTs.
• To compare the performance of Google Earth (GE) and ArcGIS (AG) for IFFT estimation.

Main Methods:

• Retrospective analysis of 1000 interfacility transports using a Bell 206 helicopter.
• Comparison of actual IFFTs with GIS-based estimates from Google Earth (GE) and ArcGIS (AG) using linear regression.
• Assessment of interrater agreement for GIS estimates using Cohen's kappa (κ).

Main Results:

• GE and AG estimates were within 1 mile of actual flight paths for 99% and 95% of runs, respectively.
• Both GE and AG strongly correlated with actual IFFTs (r² = 0.93), underestimating by approximately 2 minutes.
• Interrater agreement for both GIS platforms was statistically equivalent and "almost-perfect" (κ > 0.8).

Conclusions:

• Interfacility flight times for helicopter EMS in rural settings exhibit low variability.
• Geographical information system (GIS) software demonstrates high accuracy in predicting interfacility flight logistics.
• Public-domain Google Earth offers comparable accuracy to commercial ArcGIS for estimating flight times.