Validity of environmental audits using GigaPan^® and Google Earth Technology

Area of Science:

• Environmental Health
• Geospatial Analysis
• Public Health Research Methods

Background:

• Documenting environmental context is crucial for understanding health behaviors but remains challenging.
• Traditional direct observation methods are resource-intensive.
• Web-based platforms offer limited spatio-temporal stability for environmental auditing.

Purpose of the Study:

• To evaluate the validity of GigaPan® imagery as a novel methodology for environmental context assessment.
• To compare the accuracy of GigaPan® audits against direct observation and Google Earth audits.

Main Methods:

• Assessed 464 street segments using GigaPan® imagery, Google Earth, and direct observation.
• Quantified 37 environmental attributes across land use, traffic, safety, and amenities.
• Utilized sensitivity and specificity to determine audit validity against a gold standard.

Main Results:

• GigaPan® demonstrated high specificity (≥80%) for 31 of 37 attributes.
• Google Earth showed high sensitivity (≥80%) for 8 of 37 attributes.
• Both GigaPan® and Google Earth exhibited similar overall validity, with minor differences in specific attribute accuracy.

Conclusions:

• GigaPan® imagery is a valid and efficient tool for environmental context assessment, particularly for identifying absent features.
• Its rapid field implementation makes it a strong alternative to direct observation when time is critical.
• GigaPan® serves as a viable option when Google Earth imagery is inaccessible or temporal data is prioritized.