Affected Event Count shows the number of events impacted by a specific EMQ diagnostic issue, helping you understand the scale of data quality problems.
Affected Event Count = COUNT ( Events ) WHERE diagnostic_issue = active
| Metric | Definition |
|---|
| Events | Total events sent via Conversions API |
| diagnostic_issue = active | Filters to events with a specific data quality problem flagged by Meta |
| Metadata | |
|---|
| Type | Number |
| Data Source | Meta Ads |
| Aggregation | Count |
Example
Your Purchase event has a diagnostic issue flagged for missing phone numbers:
| Event Type | Total Events | Affected Events | Impact |
|---|
| Purchase | 12,450 | 3,847 | 30.9% affected |
| AddToCart | 45,200 | 8,104 | 17.9% affected |
| ViewContent | 128,000 | 15,360 | 12.0% affected |
How It Works
Meta’s Event Match Quality system scans your Conversions API events for data quality issues. Each diagnostic issue tracks how many events are impacted. Higher counts indicate a broader problem that affects more of your conversion data and may reduce attribution accuracy.
When to Use
| Scenario | Action |
|---|
| Prioritizing fixes | Focus on diagnostics affecting the most events first |
| Measuring improvement | Track affected count over time after implementing fixes |
| Assessing impact | Understand how widespread a specific data issue is |
| Resource allocation | Allocate engineering time based on event volume affected |
| Metric | Relationship |
|---|
| Affected Events % | Percentage version of this metric |
| Diagnostics Count | Total number of active diagnostic issues |
