Observed versus expected events
Apply reference rates to stratum-specific exposure and audit an indirectly standardized ratio.
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Each row represents one stratum: observed events, positive exposure and the applicable reference event rate per one exposure unit. Convert reference rates reported per 1,000 or 100,000 before entering them. A ratio above 1 means more observed than expected events; below 1 means fewer. This is not a causal comparison.
The starting values are hypothetical. Results update as you edit. Use aggregate or synthetic inputs only.
Calculation results
- Observed/expected ratio
- 1.2
- Expected events
- 10
- Observed events
- 12
How to interpret the output
Expected events are the sum of exposure times the external rate in each stratum. Check population eligibility, exposure units and calendar period. The observed/expected ratio uses this study’s exposure distribution and supplies no uncertainty interval.
Method reference