EquiStat

About this data

• Drive time is road travel time under a modelled OSRM profile from each Small Area to each hospital. It is not the full prehospital interval.
• 45 and 60 minutes. Coverage is shown at both. 45 minutes is the bypass window of the Major Trauma Triage Tool and the primary outcome of the published analysis; 60 minutes is the secondary threshold. "Beyond" means more than 45 or 60 minutes. PPCI centres are reported at 60 and 90 minutes, and thrombectomy centres at 60 and 120 (below).
• Deprivation is the Pobal HP Deprivation Index 2022 relative score at Electoral Division (ED) level. Deciles are population-weighted, so each holds close to 10% of the population; whole EDs sit in one decile. These ED-level figures are not the Small Area results in the published manuscripts: results depend on the size of the areas used.
• SII and RII summarise a straight-line fit across the whole deprivation distribution and can miss a gradient concentrated at one end. RII is shown as "not defined" when the fitted value at the least deprived end is zero or below, and, for % beyond a threshold, when it is 1 percentage point or below.
• Northern Ireland hospitals are off by default. They are the nine hospitals of the Northern Ireland Major Trauma Network with a Type 1 (consultant-led, 24-hour) emergency department: the Royal Victoria Hospital, Belfast, its Major Trauma Centre, and the eight hospitals that receive injured patients when it is more than 45 minutes away. Switching them on models cross-border access, assuming patients from the Republic could use them without restriction. They are not part of the Irish trauma network.
• PPCI centres give primary percutaneous coronary intervention (PPCI) for heart attack with ST elevation (STEMI). Six in the Republic are modelled: St James's Hospital and the Mater in Dublin, Cork University Hospital, University Hospital Waterford, University Hospital Galway and University Hospital Limerick. All are open around the clock except Waterford, open Monday to Friday from 9 am to 5 pm, so out of hours (the default view, 128 of the week's 168 hours) five are open. Every figure is compared with all six in hours. Coverage is reported beyond 60 and 90 minutes: 90 minutes is a common target from first medical contact to primary PCI, and the drive is only part of that time. St James's drive times were routed on the same road network as the other hospitals. The Royal Victoria Hospital, Belfast, and Altnagelvin Area Hospital, Derry, are off by default: switching them on models cross-border access, assuming they are open around the clock to patients from the Republic without restriction. The road ambulance and helicopter use the same call to mobile and on-scene times as for trauma.
• Thrombectomy centres remove the clot in a large-vessel ischaemic stroke (endovascular thrombectomy). The Republic has two, both open around the clock: Beaumont Hospital, Dublin, the National Neurosurgical Centre, and Cork University Hospital (24/7 since April 2021). Every figure is compared with the two. Coverage is reported beyond 60 and 120 minutes: 60 minutes is a common access threshold for thrombectomy, and in an Ontario study (Taghdiri et al., Can J Neurol Sci 2025) the odds of receiving it were about a fifth lower 120 minutes from a stroke centre, an uncertain estimate, and 60% lower at 240. The drive is only part of the time to treatment. Beaumont's drive times were routed on the same road network as the other hospitals. The Royal Victoria Hospital, Belfast, whose thrombectomy service has run around the clock since 14 September 2026, is off by default: switching it on models cross-border access, assuming patients from the Republic could be treated there without restriction. Thrombolysis, given at many more hospitals, is not modelled. The road ambulance and helicopter use the same call to mobile and on-scene times as for trauma.
• Helicopter times are a planning model, not service data. Each Small Area is served by the base whose helicopter would reach it first, flying a straight line at cruise speed (AW139 165 knots from Athlone and Baldonnel; EC135 137 knots from Rathcoole and Sligo, and assumed for Weston, whose aircraft is not yet known; AW109SP 154 knots from the Air Ambulance NI base near Lisburn). Every base is given 15 minutes from call to take-off and 40 minutes on scene: round numbers for planning, not measured times. The patient is flown to the nearest hospital, or the nearest MTC, switched on; every hospital is assumed to have somewhere to land. Wind, climb and approach, refuelling, aircraft availability and tasking are not modelled. The service flies by day in flyable weather only (visual flight rules), so these times do not apply at night or in poor weather. Helicopter hours: crews work 12-hour day shifts, so a base flies at most 12 hours a day, and in winter only from sunrise to sunset. That is 3,907 hours a year, 44.6% of the year's hours: 12 hours a day from mid-March to late September, falling to 7½ hours in late December (daylight at the Athlone base, 2026; every base is given the same hours, and Air Ambulance NI's 7 am to 7 pm shift, in daylight at Lisburn, comes within 1% of the same total). "Year-round" counts the faster of road ambulance and helicopter for that share of the hours and the road ambulance alone for the rest, so its figures are averages over the year's hours: they do not weigh the hours by when emergencies happen, and still assume flyable weather by day. Baldonnel is used when Athlone is not available; Weston is a possible future base. The Air Ambulance NI base, at Maze Long Kesh near Lisburn, is off by default: switching it on models cross-border tasking, assuming its helicopter could be sent to scenes in the Republic without restriction. Its position is the BT27 5RF postcode point, not the helipad itself. Unlike the drive times, helicopter times include the island Small Areas. Untick "Include call to mobile and time on scene" to see flying time only. The flight from the scene to the nearest hospital, the patient's journey alone, is the direct counterpart of the drive time.
• Road ambulances leave from the nearest of 104 stations: 92 National Ambulance Service stations (the list in the NAS reply to PQ 11063/26) and 12 full-time Dublin Fire Brigade stations, with each location checked. Drive times come from the same OSRM road network as the hospital times. From the call, they add 1.6 minutes to mobile and 20.3 minutes on scene: the National Ambulance Service's median mobilisation and on-scene times for suspected stroke before COVID-19 (Burton et al., J Am Heart Assoc 2026, Table 3). This is the best case the station map allows. Crews are often away from their base, and the measured median response, from the call coded to arrival, was 17.2 minutes. "Faster" shows, for each area, whichever of the road ambulance and the helicopter would get there first.
• Island Small Areas with no road route (17 Small Areas, 2,782 people, in the EDs of Inishmore, Aran, Cape Clear, Bear, Inishbofin and Clare Island, and part of Meenaclady) are left out of every drive-time figure and its population denominator. EDs made up only of such SAs are shown as "no road route".
• Where a collision happened says nothing about where the people involved live.
• Counts are not rates: traffic volumes and exposure are not accounted for.
• Small numbers make ED-level collision counts unstable.
• Collision road time is approximate (SA-based): it is the drive time from the Small Area containing the collision, not from the collision site. Collisions outside every Small Area boundary, or without a recorded location, have no road time.
• 2016–2024 collisions are from the Road Safety Authority collision data; recent years are provisional. 2025 fatal collisions come from a list geocoded from text descriptions, and appear only after each location has been checked. Location precision is shown on the map: solid points are RSA coordinates or a matched street; hollow points were placed near a road or at a place.

Method: docs/calculations.md in the project repository. Every figure is reproduced independently in R before release.