Systems that were not subject to the full test suite described in undergo comprehensive retrospective testing. This includes fairness testing across all protected characteristic subgroups, robustness testing (adversarial examples, input perturbation), performance benchmarking against the thresholds that the AISDP will declare, and security testing.

The results of retrospective testing become the baseline against which future changes are evaluated. The testing methodology and results are documented in Module 5, with clear indication that the testing was conducted retrospectively on the deployed system rather than during development.

Where retrospective testing reveals performance or fairness deficiencies that the AISDP thresholds cannot accommodate, remediation is required before the Declaration of Conformity can be signed. This may involve model retraining, threshold adjustment, additional mitigations, or in severe cases, system withdrawal.

Key outputs

• Comprehensive retrospective testing (fairness, robustness, performance, security)
• Baseline establishment for future change evaluation
• Transparent labelling as retrospective testing
• Module 5 AISDP documentation