2. Inclusion criteria of the studies included in the review.

Study ID	Country	Inclusion criteria
Prehospital setting
Andsberg 2017	Sweden	Suspected stroke defined as sudden onset of focal neurologic symptoms/signs, in conscious people > 18 years of age.
Berglund 2014	Sweden	Suspected stroke with symptom onset within 6 hours; ages 18–85 years; previous independence in activities of daily living; and no other acute condition requiring a priority level 1.
Bergs 2010	Belgium	Acute neurologic event without clear origin, altered level of consciousness, convulsions, syncope, headache, and symptoms of weakness, dizziness or decreased well‐being, aphasia, visual impairment, weakness in arms or legs (or both) and facial paralysis. People age < 18 years, trauma, unconsciousness (GCS ≤ 8), and people transported to another hospital were excluded.
Bray 2005a	Australia	Paramedics were instructed to complete a MASS assessment sheet on all designated EMS dispatches for 'stroke' that were symptomatic, conscious and to be transported to Box Hill Hospital. Paramedics were also asked to complete a MASS sheet for other people suspected of stroke where a focal neurologic deficit (i.e. unilateral limb weakness, speech disturbance) was noted during an initial exam.
Bray 2010	Australia	People transported by EMS with documented MASS assessments of hand grip, speech, and facial weakness; and people with a discharge diagnosis of stroke or TIA included in the stroke/TIA registry. People who were unconscious or asymptomatic at the time of paramedic assessment were excluded.
Chen 2013	China	Baseline screen criteria for the 'target stroke' population were referred from the original LAPSS study including age ≥ 18 years; neurologically relevant complaints; absence of coma and non‐traumatic. The neurologically relevant complaints were identified with 6 categories, including altered level of consciousness; local neurologic signs; seizure; syncope; head pain and the cluster category of weak/dizzy/sick.
Chenkin 2009	Canada	People screened as positive by paramedics using OPSST and transported directly to a predesignated stroke center based on the person's current geographic location. Also all people with suspected stroke arriving by ambulance who did not have a positive screen were examined.
Ding 2009	China	People with acute neurologic problems and non‐traumatic, non‐comatose, non‐obstetrics presentation transported to 3 local hospitals.
English 2018	USA	People identified by EMS dispatchers as potential stroke/TIA cases were included. Those who met any of the following inclusion criteria were selected: positive CPSS in field; EMS impression of cerebrovascular accident or TIA; acute stroke pager activation in the ER; discharge diagnosis of cerebrovascular accident or TIA. People were excluded if they met any of the following: hospital arrival via helicopter, outside hospital transfer, direct admission without ER evaluation or last known well time > 6 hours.
Fothergill 2013	UK	People aged > 18 years if they presented with symptoms of stroke, were assessed by participating ambulance clinicians using the ROSIER, and conveyed to the Royal London Hospital. Those who were ages < 18 years, not assessed using the ROSIER or transferred to another hospital were excluded.
Frendl 2009	USA	All people transported to the Duke University Medical Center and coded by EMS as having a possible stroke or TIA were identified retrospectively by review of computerized and paper‐based paramedic records for the year before and after training, regardless of whether or not an abnormality was noted for a CPSS item. These records were then compared with the hospital's prospective stroke registry for the same period. The stroke registry includes all patients admitted to the study hospital with a discharge diagnosis of stroke or TIA.
Kidwell 2000	USA	A 'target stroke' population was predefined as non‐comatose, non‐trauma patients with symptom duration < 24 hours with ischemic stroke, intracerebral hemorrhage, or TIA if the person was still symptomatic at the time of initial paramedic examination. These people constituted the population the LAPSS was designed to identify.
Kim 2017	Republic of Korea	People suspected of stroke and transported to a single hospital by EMS paramedics and people with true stroke without stroke recognition by EMS (retrospective sample), for a period of 12 months (data extracted from EMS records, including CPSS score).
Mingfeng 2012	China	All people > 18 years with suspected stroke or TIA with symptoms or signs seen by an emergency physician in the prehospital setting were included. According to the ASA guidelines, people who got ≥ 1 of these suggestive clinical elements as follows were defined as people with suspect acute stroke or TIA. The suggestive clinical elements included sudden weakness or numbness of the face, arm or leg, especially on 1 side of the body; sudden confusion, trouble speaking or understanding; sudden trouble seeing in 1 or both eyes; sudden trouble walking, dizziness, loss of balance or co‐ordination; or sudden severe headache with unknown cause.
Mingfeng 2017	China	All people > 18 years with suspected stroke or TIA who presented to 2 primary care centers during the recruitment period. The following clinical signs were considered suggestive of stroke: numbness or weakness in the face, arms or legs (especially on 1 side of the body); confusion, difficulty in speaking or understanding speech; vision disturbance in 1 or both eyes; dizziness, walking difficulties, loss of balance or co‐ordination; severe headache without known cause. Patients were excluded if they had head trauma or surgery in recent months; previous stroke with neurologic deficits or incomplete medical testing.
Ramanujam 2008	USA	People age ≥ 18 years identified as having stroke in the prehospital phase using the MPDS Stroke protocol by emergency medical dispatchers or by use of CPSS by paramedics. People taken to other acute care hospitals not participating in the study, people with a dispatch determinant of stroke who were not transported by City EMS agency (SDMSE) to participating hospitals, people in the stroke registry not transported by SDMSE or people with no final outcome data were excluded from the study.
Studnek 2013	USA	People were included if they received a prehospital MedPACS screen and were transported to 1 of 7 local hospitals. The EMS agency protocols stipulated that a MedPACS screen be performed on all people who had signs or symptoms of acute stroke or TIA. People with no documented MedPACS screen, who nevertheless ended up with a hospital diagnosis of stroke were excluded from the primary analysis. People were also excluded if they were < 18 years, if they were transported to any medical facility other than those in the inclusion criteria or if they were secondary transports from a regional facility.
ER setting
Jackson 2008	UK	Consecutive participants admitted to a single ER identified on routine initial triage as having possible or suspected stroke.
Jiang 2014	China	Consecutive participants ≥ 18 years old, presenting to the ER with symptoms or signs suggestive of stroke or TIA. The following people were excluded: traumatic brain injury with an external cause such as motor vehicle crashes and falls; incomplete medical records; people who did not present first to the ER (e.g. direct admission to a ward); and in accordance with the criteria for the original ROSIER scale, people with subarachnoid hemorrhage, subdural hematoma and TIA without symptoms and signs during this period.
Lee 2015	Korea	People with suspected acute stroke who were admitted to the ER.
Nor 2005	UK	People age > 18 years with suspected stroke or TIA with symptoms or signs seen by ER physicians in the ER were included.
Vanni 2011	Italy	Consecutive adults with suspected stroke who presented to the ERs of 3 hospitals. Inclusion criteria were the presence at triage of acute focal neurologic deficit (including also signs of posterior circulation ischemia: vertigo, double vision, visual field defects or disorders of perception, balance, and co‐ordination) or a 118 (local EMS) dispatch of suspected stroke. Exclusion criteria were major trauma and coma (GCS score ≤ 8). People with terminal illnesses (life expectancy < 3 months) were also excluded.
Whiteley 2011	UK	Consecutive participants with suspected acute stroke who presented to the ER of the Western General Hospital, Edinburgh, while the study neurologist was available. Acute stroke was suspected in people: whose symptoms began < 24 hours before admission; who were still symptomatic at the time of assessment; and in whom a general practitioner, a paramedic or a member of the emergency‐room staff had made a diagnosis of 'suspected stroke'.

ASA: American Stroke Association; CPSS: Cincinnati Prehospital Stroke Scale; EMS: emergency medical services; ER: emergency room; GCS: Glasgow Coma Scale; LAPSS: Los Angeles Prehospital Stroke Scale; MASS: Melbourne Ambulance Stroke Scale; MPDS: medical priority dispatch system; OPSST: Ontario Prehospital Stroke Screening Tool; ROSIER: Recognition of Stroke in the Emergency Room; SDMSE: San Diego Medical Services Enterprise; TIA: transient ischemic attack.