Data Platform

Annotation Quality

Multi-layer QA frameworks that guarantee annotation accuracy, inter-annotator consistency, and production-ready data at every stage of your pipeline.

Our Approach

Quality is Not an Afterthought

At CoreLabel, quality assurance is embedded at every stage — not bolted on at the end.

Our QA framework combines inter-annotator agreement checks, senior reviewer sign-off, and automated consistency scans to deliver datasets you can trust in production. Every label is traceable, every batch is auditable.

Quality Assurance for labelled data at CoreLabel
Inter-Annotator Agreement

Multiple independent annotators label each sample independently. Agreement is measured using Cohen's kappa, with a minimum threshold of ≥ 0.75 required before a batch is approved. Disagreements below threshold are escalated to senior reviewers — ensuring labels reflect genuine consensus, not a single opinion.

Automated Consistency Scans

Rule-based and ML-assisted checks flag statistical outliers, class imbalance, and schema violations before a batch ever leaves our pipeline.

Senior Review & Sign-off

Every batch undergoes a final pass by a domain-experienced reviewer who validates edge cases, ambiguous instances, and guideline adherence.

Full Audit Trail

Each annotation is timestamped and linked to the annotator, reviewer, and guideline version — giving you complete traceability for compliance and model debugging.

Quality Metrics Dashboard

Receive per-batch accuracy scores, Cohen’s kappa coefficients, and defect-rate trends so your ML team can make data-driven decisions on training set composition. Every metric is exportable and auditable.

Continuous Feedback Loops

Model performance signals feed back into labeling guidelines and annotator training, continuously raising the quality floor across projects.

99.2%
Average Label Accuracy
≥ 0.75
Cohen’s Kappa (IAA)
< 2%
Defect Rate at Delivery
3-tier
QA Review Structure
100%
Batches Fully Auditable

The QA Lifecycle

01
Guideline Setup
Annotation guidelines authored with your domain experts and versioned for traceability.
02
Annotator Training
Annotators complete guideline training and pass a calibration batch before working on live data.
03
Primary Annotation
Independent annotators label each sample following the versioned guidelines.
04
IAA Check
Inter-annotator agreement is computed using Cohen’s kappa. Batches scoring below ≥ 0.75 are automatically flagged and routed back for re-annotation before senior review.
05
Senior Review
Flagged items and a random sample of all batches are reviewed by senior annotators.
06
Delivery & Reporting
Clean dataset delivered with full QA metrics report and audit trail.

Ready to Raise the Quality Bar?

Tell us about your project and we will design a QA framework that matches your accuracy requirements.