Data Quality Standard¶
Ready
Purpose. Defines what "good enough" data means in measurable terms — the dimensions, how they are measured, the thresholds that apply, and who acts when a threshold is breached.
When to use it. Alongside the data governance policy, and specifically before any dataset is used to train or evaluate a model. Review thresholds annually.
How to use it. Do not attempt all six dimensions across the whole estate at once. Pick your two or three highest-value domains, set thresholds, and measure those until the process is real — then extend. A standard measured nowhere is worse than no standard, because it implies assurance you do not have.
Closes assessment gaps
This template addresses Q12, Q28 in the readiness assessment.
The template¶
1. Quality dimensions¶
| Dimension | Question it answers | Example measure |
|---|---|---|
| Completeness | Is the expected data present? | % of mandatory fields populated |
| Accuracy | Does it reflect the real world? | % matching a verified source |
| Timeliness | Is it current enough to use? | Age at point of use vs. requirement |
| Consistency | Does it agree across systems? | % of records matching across systems |
| Validity | Does it conform to its rules? | % passing format / range rules |
| Uniqueness | Are there duplicates? | % duplicate records |
2. Thresholds¶
Thresholds are set per domain by the Data Owner, based on use. Data feeding a regulatory return or a high-risk AI system needs tighter thresholds than data feeding an internal dashboard.
| Domain | Dimension | Threshold | Measure | Frequency | Owner |
|---|---|---|---|---|---|
| Customer | Completeness | ≥ 98% | [rule] | Daily | [role] |
| Customer | Uniqueness | ≥ 99% | [rule] | Weekly | [role] |
| [domain] | [dimension] |
3. Quality for AI training data¶
Additional requirements where data trains, validates, or tests a model — this is the Art. 10 obligation in practice:
| Requirement | What it means | Evidence |
|---|---|---|
| Relevance | The data suits the stated purpose. | Documented rationale in the Model Card / Model Risk Documentation |
| Representativeness | It reflects the population the system will act on. | Distribution analysis vs. target population |
| Bias examination | Known skews are identified and addressed. | Bias assessment; mitigation record |
| Provenance | Source and licence are known and lawful. | Entry in Data Asset Register |
| Split integrity | Train/validation/test do not leak into each other. | Split methodology documented |
Representativeness is not a percentage
A dataset can be 99% complete and still unrepresentative of the people the system will affect. Completeness measures the data you collected; representativeness asks who is missing from it entirely.
4. Measurement & reporting¶
Scores are produced monthly (weekly for data feeding a high-risk system), published to [location], and summarised in KPI / KRI Dashboard. Trend matters more than absolute level.
5. Breach handling¶
| Severity | Definition | Response | Timeframe |
|---|---|---|---|
| Critical | Regulatory or high-risk AI impact | Escalate to committee; consider suspending use | 24 hours |
| Major | Material business impact | Owner-led remediation plan | 5 working days |
| Minor | Limited impact | Backlog for next cycle | 30 days |
Breaches are recorded in the Issue & Incident Log.
6. Review¶
| Version | Date | Owner | Approved by |
|---|---|---|---|
| 0.1 | [date] | [role] | [committee] |
Adaptation notes¶
- Small organisations: Measure completeness and validity only, on your two most important domains. That covers most real-world failures at a fraction of the cost.
- Regulated financial services: Align with BCBS 239 and make lineage evidence explicit — supervisors ask to trace a reported figure back to source.
- ML-heavy organisations: Section 3 is the section that matters. Automate representativeness and drift checks into the training pipeline so the evidence is a by-product rather than a project.
Related¶
- Data Governance Policy — Ready
- Data Asset Register — Ready
- Model Card / Model Risk Documentation — Ready
- KPI / KRI Dashboard — Ready
Not legal advice
These templates are a head start, not a substitute for professional judgement. Adapt them to your jurisdiction, sector, and risk appetite, and have qualified counsel review anything material before you rely on it.