Uppsala–Sydney: A Follow-the-Sun Model for Night-Time Emergency Reporting

Critical operational question

The principal uncertainty was not whether a radiologist in Sydney could interpret the images. It was whether the examinations—particularly larger CT datasets—could be transferred rapidly enough for emergency use.

Follow-the-Sun Reporting

The central concept was to move the reporting workload rather than require every interpretation to be completed by a radiologist working overnight. Night-time examinations in Uppsala were reviewed during local daytime hours in Sydney.

Parallel Reporting Evaluation

During a one-week evaluation in spring 2005, 75 examinations were interpreted both in Sydney and at Akademiska Hospital in Uppsala, allowing remote and local report availability to be compared.

Cross-Continental Image Transfer

Digital examinations were transferred from Sweden to Australia over the internet. The researchers recorded download time for 75 examinations and report-return time for 24 reports.

Conventional Radiography Transfer

All conventional radiological examinations were downloaded in less than 60 minutes, showing more consistent performance for smaller imaging datasets.

CT Dataset Transfer

Large CT studies created the greatest technical challenge. Among CT examinations containing more than 65 images, only 44% completed downloading within 60 minutes.

Remote Interpretation

Once the images were available, the Sydney radiologist completed reports in under 10 minutes. Most remote-pathway delay therefore came from image transfer rather than interpretation.

Report Return and Comparison

The Sydney report was available in Uppsala within 30 minutes of the in-house report in 79% of evaluated examinations.

Faster Than Local in Some Cases

According to Uppsala University’s account, 17% of Sydney reports were completed before the report produced locally in Uppsala.

What the numbers reveal

The results distinguish reporting time from transmission time. Once an examination had downloaded, the Sydney radiologist could complete the interpretation quickly. Large image datasets were the main obstacle to a faster end-to-end workflow.

PUBLISHED STUDY

Title: Teleradiology Uppsala–Sydney for Nighttime Emergencies: Preliminary Experience

Journal: Acta Radiologica

Publication year: 2007

Volume and issue: 48(8)

Pages: 851–853

Authors: H. Eklöf, E. Radecka and P. Liss

DOI: 10.1080/02841850701422120

View the PubMed record • View the Uppsala University summary

79%

Remote reports delivered within 30 minutes of the local report

In most evaluated examinations, the Sydney report was available in Uppsala no more than 30 minutes after the locally prepared report.

Under 10 Minutes

Remote report preparation time

After the images became available, the Sydney radiologist completed the interpretation and report in less than 10 minutes.

17%

Sydney reports completed before local reports

Some reports prepared in Australia were available before those produced at the originating hospital.

44%

Large CT studies downloaded within 60 minutes

Only 44% of CT examinations with more than 65 images completed downloading within an hour, identifying large datasets as the main bottleneck.

Daytime Expertise for Night-Time Demand

The case showed how a hospital could potentially obtain overnight reporting from a radiologist working ordinary daytime hours in another part of the world. This approach later became widely described as a follow-the-sun or time-zone-based reporting model.

Fast Interpretation After Image Availability

The under-10-minute report preparation time demonstrated that the reporting component could be efficient once the radiologist had access to the complete examination.

Potentially Reduced Night-Shift Pressure

The study was motivated partly by the possibility of improving radiologists’ working hours and reducing dependence on overnight reporting.

Comparable Operational Timing

In 79% of examinations, the remote report reached Uppsala within 30 minutes of the local report, suggesting that cross-continental reporting could operate within a practically relevant timeframe for many studies.

Transmission as the Critical Dependency

The performance differences between conventional studies and large CT examinations established an important lesson: a remote reporting workflow can only be as fast as its image-transfer infrastructure.

Evidence boundary

The published evaluation was preliminary and involved 75 examinations. It measured image-download and reporting times but did not establish improvements in mortality, diagnostic accuracy, patient outcomes or financial savings. Potential benefits to patient safety, work schedules and costs were discussed but not directly measured.

Reporting Capacity Can Cross Time Zones

A hospital’s night-time workload can be allocated to radiologists working daytime hours elsewhere, reducing the need to treat geography as a fixed operational limitation.

Transmission and Interpretation Are Separate Measures

The radiologist completed reports in under 10 minutes, yet large CT studies could take much longer to download. Measuring only reporting time would have hidden the main workflow constraint.

Modality Affects Remote Performance

Conventional radiography transferred more consistently than large CT datasets. Teleradiology capacity must be planned according to image volume, not simply case count.

Parallel Evaluation Builds Confidence

Comparing remote reports with reports produced at the originating hospital allowed the project to assess whether the international workflow introduced meaningful delay.