The Thrombectomy System Score (TSS) is a new system-level measure designed to assess how effectively stroke networks deliver mechanical thrombectomy (MT). It focuses on access, timeliness and quality across the whole thrombectomy pathway, rather than on individual hospitals alone.
The TSS brings together a small number of key indicators that reflect different stages of the pathway, from referral and transfer through to treatment, imaging and workforce development.
The purpose of the TSS is to:
- support system-wide quality improvement,
- highlight variation in access and performance, and
- help thrombectomy networks identify where pathway changes could improve outcomes for patients.
TSS indicators and weightings
The Thrombectomy System Score is made up of seven indicators, each contributing a weighted proportion to the overall score.
| Indicator | Description | Weighting |
| TS1 | Thrombectomy rate: MT rate for the system as a whole | 25% |
| TS2 | Variation in access 1: Percentage difference in MT rate between the lowest-performing spoke and the hub | 10% |
| TS3 | Variation in access 2: Proportion of all MT referrals originating in spokes compared with the proportion of all strokes admitted to spokes | 10% |
| TS4 | Door-in-door-out time: Median DIDO for all referred patients in the system | 25% |
| TS5 | Door-to-puncture time: Median DTP for all treated patients within the system | 20% |
| TS6 | Training: Proportion of procedures involving a second scrubbed operator | 5% |
| TS7 | Advanced imaging: Proportion of ischaemic strokes receiving advanced imaging across the system | 5% |
Why this approach is being introduced
Mechanical thrombectomy outcomes depend not only on specialist centres, but on how well the entire stroke system functions, including referral pathways, transfer processes, and collaboration between hub and spoke hospitals.
The TSS has been developed to:
- move beyond single-metric assessment,
- provide a consistent national framework for system-level review, and
- encourage shared responsibility across thrombectomy networks.
The focus is on understanding variation and supporting improvement, rather than ranking individual providers.
Rollout and reporting timeline
The Thrombectomy System Score will be introduced in phases to allow teams time to understand the measures, review their data and engage with available support before public reporting.
Reporting phases
- Report 1: October–December 2025
- Network-level metrics only (note: TSS scores will not be applied)
- Internal use only
- No scores published
- Report 2: January–March 2026
- Network-level metrics and TSS scores
- Internal use only
- Report 3: April–June 2026
- Network-level metrics and TSS scores
- Public reporting
This phased approach is intended to support transparency while allowing teams time to familiarise themselves with the measures and address any data or pathway issues ahead of public release.