If you use a CPAP or BiPAP machine and want to understand your therapy data, you've probably heard of OSCAR (Open Source CPAP Analysis Reporter). It's been the go-to tool for PAP data analysis for years, and for good reason. But OSCAR and AirwayLab solve different problems. This article explains what each tool does well, where they differ, and why many users benefit from using both.
What OSCAR Does Well
OSCAR deserves its reputation. It's a mature, reliable desktop application with features no other free tool matches:
- Interactive waveform browsing with zoom, pan, and event marking at breath-by-breath resolution
- Multi-device support including ResMed, Philips, F&P, and others
- Historical data stored locally with long-term trend views across months and years
- Detailed event logs showing individual apnea, hypopnea, and leak events on a timeline
- Active community on ApneaBoard.com and other forums, with years of shared knowledge
For manual waveform inspection and event-by-event review, OSCAR is hard to beat. If you need to zoom into a specific 30-second window and examine individual breaths, OSCAR is the right tool.
Where OSCAR Stops and AirwayLab Starts
OSCAR shows you what happened. AirwayLab tells you what it means. The difference is automated analysis:
No Flow Limitation Scoring
OSCAR displays the raw flow waveform but doesn't compute flow limitation metrics. You have to visually identify flat-topped breaths yourself, which requires training and is subjective. AirwayLab runs four algorithms automatically.
No RERA Detection
OSCAR can't identify sequences of flow-limited breaths that end in arousals. AirwayLab's NED engine detects these automatically and estimates a RERA index and Respiratory Disturbance Index.
No Composite Metrics
AirwayLab computes the Glasgow Index (9-component breath shape score), FL Score, Regularity, Periodicity, and more. These synthesise thousands of breaths into actionable numbers you can track over time.
Desktop-Only
OSCAR requires installation on Windows, macOS, or Linux. AirwayLab runs in your browser on any device. Upload your SD card, get results, no installation needed.
Side-by-Side Comparison
| Feature | OSCAR | AirwayLab |
|---|---|---|
| Interactive waveform zoom | Yes | Viewer only |
| Multi-device support | Yes | ResMed only |
| Flow limitation scoring | No | 4 engines |
| RERA detection | No | Yes (NED) |
| Glasgow Index | No | Yes |
| Oximetry analysis | Basic | 17 metrics |
| AI-powered insights | No | Yes (opt-in) |
| Runs in browser | No | Yes |
| Privacy | Local files | Browser-only |
| Open source | Yes | Yes (GPL-3.0) |
| Community data contribution | No | Yes (opt-in) |
| Cost | Free | Free core |
Privacy: Both Tools Get It Right
Both OSCAR and AirwayLab keep your data under your control. OSCAR stores everything locally on your computer. AirwayLab processes everything in your browser using Web Workers, and no data leaves your device unless you explicitly opt in to features like AI insights or community data contribution.
This stands in contrast to manufacturer apps (myAir, DreamMapper) that upload your data to corporate servers and may share it with insurance providers. Both open-source tools give you the analysis without the privacy trade-off.
Using Both Tools Together
OSCAR and AirwayLab aren't competitors; they're complementary. A practical workflow:
1. Start with AirwayLab for the big picture
Upload your SD card, get your Glasgow Index, FL Score, RERA estimate, and IFL Risk Score. These composite metrics tell you whether flow limitation is a problem and how severe it is. The traffic light system makes interpretation straightforward.
2. Use OSCAR to investigate specifics
If AirwayLab flags elevated flow limitation in the second half of the night (H2), open that session in OSCAR and zoom into the waveforms. Look for the specific events and patterns. OSCAR's interactive zoom is unmatched for this kind of detailed inspection.
3. Track trends in AirwayLab, verify in OSCAR
After a pressure or EPR change, monitor your AirwayLab metrics across nights. If a metric shifts significantly, confirm the change by inspecting representative waveforms in OSCAR. This gives you both statistical confidence and visual verification.
Which Tool Is Right for You?
OSCAR is best if you...
- Need to browse individual waveforms interactively
- Use a non-ResMed device (Philips, F&P)
- Want years of historical data in one view
- Prefer a desktop application
- Already know how to read flow waveforms
AirwayLab is best if you...
- Want automated flow limitation analysis
- Need a quick summary of how your therapy is working
- Want metrics that go beyond AHI (Glasgow, NED, RERA)
- Prefer browser-based tools with no installation
- Want AI-powered insights about your patterns
- Need exportable reports for your clinician
Learn More
Beyond AHI: Why Your Sleep Apnea Score Might Be Misleading You — the research case for metrics beyond AHI.
Understanding Flow Limitation — what flow limitation is and how it affects your sleep.
AirwayLab Methodology — detailed documentation of all four analysis engines.
OSCAR Official Site — download and documentation for OSCAR.
Try AirwayLab Free
Upload your ResMed SD card and get flow limitation analysis in minutes. Four research-grade engines, composite metrics, RERA detection, and trend tracking. No installation, no account required, 100% private.