Patient characteristics. Intervention Comparison Length of followup. Outcome measures. Number of patients. Evidence level.

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1 5.0 Rapid recognition of symptoms and diagnosis 5.1. Pre-hospital health professional checklists for the prompt recognition of symptoms of TIA and stroke Evidence Tables ASM1: What is the accuracy of a pre-hospital professional assessment tool/checklist for identifying signs and symptoms of suspected stroke/tia? Reference Harbison J, Hossain O, Jenkinson D et al. Diagnostic accuracy of stroke referrals from primary care, emergency room physicians, and ambulance staff using the face arm speech test. Stroke. 2003; 34(1): Ref ID 1048 Study type Evidence level Prospective cohort Ib+ USA Number of patients Patient characteristics N=487 Patients referred to an acute stroke unit Patient population: mean age 72 yrs, 52% female Stroke type: 26% total anterior cerebral infarction, 36% partial anterior cerebral infarction, 18% lacunar cerebral infarction, 10% posterior circulation infarction, 10% primary Intervention Comparison Length of followup Paramedics who used a rapid ambulance protocol, which incorporates the Face Arm Speech Test (FAST) Primary care doctors referring directly to the acute stroke unit Emergency room personnel Patients referred over 6 mths Outcome measures Diagnostic accuracy Performance compared to doctors and ER physicians Source of funding None reported

2 intracerebral infarction (N=62) Effect *Accuracy The positive predictive value (PPV) for ambulance staff was 78% (95%CI 72 to 84%), for emergency room (ER) staff 71% (64 to 78%) and for primary care doctors 71% (65 to 77%). A stroke/tia detection rate (diagnostic accuracy) was estimated for the ambulance paramedics by assuming all strokes/tias that were taken by ambulance to the ER were referred to the acute stroke unit. This gave an upper estimated of sensitivity of 79% 1 *Performance Ambulance paramedics referred more total anterior circulation infarcts than PCDs or ER doctors (39% of total admissions, 14% and 24% respectively; p<0.01). A higher proportion of lacunar strokes were admitted by PCDs than by ER of ambulance personnel (24%, 17% and 12%; p<0.05). Ambulance paramedics recognised three of seven posterior circulation strokes referred to them (43%). However, these seven patients represent only 24% of posterior circulation strokes referred to the stroke service. There were no statistical differences between the ambulance paramedics, primary care doctors and emergency room personnel on the number of non-stroke cases referred to the stroke service (23%, 29% and 29%, respectively; NS) Mohd Nor AM, Davis J, Sen B et al. The Recognition of Stroke in the Emergency Room (ROSIER) scale: development and validation of a stroke recognition instrument.[see comment]. Lancet Prospective cohort Ib+ UK N=343 (Results of validation phase only) Stroke or TIA N=176 Non-stroke N=167 Patients age 18 yrs or over with suspected stroke or TIA Stroke or TIA population: 58% women, mean age 71 yrs, presentation within 3 hrs 42%, presentation The ROSIER proforma was completed by ER physicians on all patients with suspected stroke or TIA before CT or MRI scan and with no prior knowledge of the final diagnosis All patients underwent CT or MRI, or both Final diagnosis made by the consultant stroke physician, after assessment and review of clinical symptomatology and brain imaging findings 9 months (length of validation phase) Diagnostic accuracy The Stroke Association UK 1 It was not possible to calculate an accurate diagnostic sensitivity in any referring group because non-referrals to the acute stroke unit were not reviewed

3 Neurology. 2005; 4(11): Ref ID 2356 within 24 hrs 95% and previous stroke 18% Stroke classification: total anterior circulation stroke 12%, partial anterior circulation stroke 22%, lacunar stroke 29%, posterior circulation stroke 16%, primary intracerebral haemorrhage 8%, TIA 13% Patient population (non-stroke): 59% female, median age 72yrs, presentation within 3 hrs 54%, within 24 hrs 97%, previous stroke 18%

4 Effect *Time to assessment The median time from admission to assessment by the research neurologist (95% of cases) and senior physicians of the stroke team was 300 mins (IQR ). *Accuracy A cut-off of 1+ or above for stroke, the ROSIER scale had a sensitivity of 93%. In the prospective validation phase, the proportion of non-stroke patients referred to the stroke team decreased (37% vs 49%; p=0.01) compared with the development phase. The ROSIER scale incorrectly diagnosed 17/160 (10%; 10 false positive, 7 false negative). *ROSIER compared with CPSS, FAST and LAPSS CPSS was defined as positive if facial weakness, arm weakness, or speech disturbance (or any combination of these) was present. FAST was defined as positive if facial weakness, arm weakness or speech deficits were present and Glasgow Coma Score was more than 6. LAPSS was defined as positive if arm weakness, grip weakness, or facial weakness was present and blood glucose was within the range 2.8 to 22.2 mmol/l, age greater than 45 yrs, no seizure activity, symptoms present for less than 24 hrs and the patients was not wheelchair bound or bed-ridden (pre-stroke modified Rankin Scale <5). FAST scores were completed for 49 of 91 (54%) stroke patients taken to ER by ambulance paramedics. ROSIER was superior to FAST (sensitivity 92% vs 54%, specificity 96% vs 91%, PPV 96% vs 88%, NPV 92% vs 64%). The total ROSIER scores were related to stroke severity and subtype. Patients with total anterior circulation infarction had the highest median score of +4 (IQR 2.25 to 4) and posterior circulation infarction showed the lowest median score of +1 (IQR 0 to 2). The median scores for primary intracerebral haemorrhage, partial anterior circulation infarction and lacunar infarction were +2.5 (1.25 to 3.75), +1 (1 to 3) and +2 (2 to 3) respectively. Seven patients with confirmed sub-arachnoid haemorrhage had total scores of zero or less (-2 in four, -1 in three). ROSIER % (95%CI) CPSS % FAST % LAPSS % Sensitivity 93 (89-97) 85 (80-90) 82 (76-88) 59 (52-66) Specificity 83 (77-89) 79 (73-85) 83 (77-89) 85 (80-90) Positive Predictive Value 90 (85-95) 88 (83-93) 89 (84-94) 87 (82-92) Negative Predictive Value 88 (83-93) 75 (68-82) 73 (66-80) 55 (48-62)

5 Mohd Nor A, McAllister C, Louw SJ et al. Agreement between ambulance paramedic- and physicianrecorded neurological signs with Face Arm Speech Test (FAST) in acute stroke patients. Stroke. 2004; 35(6): Ref ID 1056 Prospective cohort (validation phase reported here) Ib+ UK N=278 suspected stroke patients N=189 stroke TIA N=28 Patients over 18 yrs of age with signs and symptoms of suspected stroke/tia seen by ER physicians in the ER Patient population (stroke/tia): 53% male, median age 76yrs Stroke subtype: total anterior circulation infarction 27%, partial anterior circulation infarction 19%, lacunar circulation infarction 23%, posterior Training in the Face Arm Speech Test (FAST), an integral component of the paramedic training module. FAST is a three-item instrument assessing facial weakness, arm weakness and speech disturbance. Paramedics recorded the FAST findings on the patient s ambulance report form. All patients with a confirmed stroke/tia were examined by a trainee stroke neurologist or senior admitting neurologist. The majority (95%) of suspected stroke patients in this study had their history reviewed and full neurological examination performed by the trainee stroke neurologist. In the remainder (5%) the history and examination findings recorded by the senior stroke physician who had seen the patient were taken Validation phase (9 mths) Accuracy The Stroke Association

6 circulation infarction 5%, primary intracerebral haemorrhage 13% and TIA 13% retrospectively from patients clinical notes. NOTE: analysis was confined to confirmed acute stroke case. The three signs compared were facial weakness, arm weakness and speech disturbance. TIA and nonstrokepatients were excluded The median time delay from assessment by the paramedic to examination by the trainee stroke neurologist or admitting stroke physician for cases of confirmed stroke was 18 hrs (interquartile range 8 to 24 hrs)

7 Effect (validation phase) *Paramedic FAST deficits compared to physician assessment Facial weakness was assessed as present by the physician and in 108 cases assessed by the paramedics but missed in 22 cases. Facial weakness was assessed as not present by the physician but present in 19 cases and absent in 38 cases as assessed by the paramedics. Overall, there was moderate agreement for facial weakness (k=0.49; 95%CI 0.36 to 0.62). Arm weakness was assessed as present by the physician and in 169 cases by the paramedic and absent in 3 cases. Overall, there was good agreement (k:0.61 to 0.80) for arm weakness (k=0.77; 95%CI 0.55 to 0.99). Speech disturbance was assessed as present by the physician and present in 129 cases assessed by the paramedics and absent in 12 cases. Overall, there was good agreement (k=0.69; 95%CI 0.56 to 0.82) Complete agreement for each neurological sign was 78% facial weakness, 98% arm weakness and 89% speech disturbance. In the non-stroke patients (N=61) the disagreement was mainly because of paramedics but not the assessing physicians recording a sign as present. Bray JE, Martin J, Cooper G et al. An interventional study to improve paramedic diagnosis of stroke. Prehospital Emergency Care. 2005; 9(3): Ref ID 2357 Prospective interventional cohort II+ Australia N=18 (FAST paramedics) N=43 (non- FAST paramedics) Paramedics were assessed for baseline stroke knowledge, and ability to diagnose stroke. Final hospital diagnosis made by senior medical staff Retrospective review of all confirmed stroke or TIA for the 12- month period prior to the intervention. 1 yr (development phase) 9 mths (validation phase) Paramedic diagnosis Documentation of stroke onset Paramedic prenotification Assessed patient population (retrospective and prospective combined): 55% female, mean age 79 yrs, ischaemic FAST training: One-hour education session covering stroke etiology, symptoms, risk factors, assessment, documentation of onset, diagnosis, management, and the use of the prehospital stroke assessment tool. None reported

8 stroke 72%, haemorrhagic stroke 18%, TIA 10% All paramedics completed a questionnaire to assess knowledge of stroke To standardise the prehospital assessment of stroke, FAST study paramedics were instructed in the use of the Melbourne Ambulance Stroke Screen (MASS) tool to assist the diagnosis of stroke. The MASS is a combination of two validated prehospital stroke assessment tools, the Los Angeles Prehosptial Stroke Screen (LAPSS) and the Cincinnati Prehospital Stroke Scale

9 (CPSS) MASS criteria: History items age>45yrs, no history of seizure of epilepsy, not wheelchair bound, blood glucose 2.8 and 22.1 mmol/l. Motor items unilateral facial droop, unilateral hand grip weakness, unilateral arm drift and abnormal speech. History items 1-4 must all be yes in the presence of at least one motor item for MASS criteria to be met and stroke diagnosis given

10 Effect *MASS vs non-mass paramedics For the MASS paramedics sensitivity improved from 78% (95%CI 63 to 88%) to 94% (95%CI 86 to 98%) (p=006). Stroke diagnosis in the control paramedic group did not change significantly (78 vs 80%; NS). For the MASS paramedics the sensitivity of stroke diagnosis was greater when the MASS tool was used compared with strokes for which there was no documented assessment (95 vs 70%; p=0.001). Bray JE, Martin J, Cooper G et al. Paramedic identification of stroke: community validation of the melbourne ambulance stroke screen. Cerebrovascular Diseases. 2005; 20(1): Ref ID 2359 Prospective cohort II+ Australia N=18 paramedics N=100 MASS assessments Of the 100 patients, 73 (73%) had a final discharge diagnosis stroke or TIA and 27 (27%) were stroke mimics. Of the 73 stroke patients, 68% were ischaemic, 13% haemorrhagic and 24% TIA with a mean age of 76yrs FAST paramedics were given a 1hr education session on the pathogenesis and management of acute stroke. Paramedics were instructed to complete a MASS assessment sheet on all designated EMS dispatches for stroke that were symptomatic and conscious NA 12 months Sensitivity Specificity PPV NPV Positive likelihood ratio Negative likelihood ratio Accuracy None reported

11 Effect The overall test for significance between the MASS and CPSS (p=0.04) and the MASS and CPSS (p=0.04) and the MASS and LAPSS (p=0.003) was significant. The sensitivity of the MASS (90%) showed statistical equivalence to the sensitivity of the CPSS (90 vs 95%, NS) and superiority to the LAPSS (90% vs 78%, p=0.008). The specificity of the MASS was equivalent to that of the LAPSS (74 vs 85%, p=0.25) and superior to the CPSS (74 vs 56%, p=0.007). The MASS tool demonstrated 100% sensitivity for detection of 13 ischaemic stroke patients who were eligible for thrombolytic therapy. There were 14 patients misidentified by the MASS; 7 strokes did not meet the criteria (false negatives) and 7 mimics did meet criteria (false positives). LAPSS (95% CI) CPSS MASS Sensitivity 78% (67-87) 95% (86-98) 90% (81-96) Specificity 85% (65-95) 56% (36-74) 74% (53-88) Positive Predictive Value 93% (83-98) 85% (75-92) 90% (81-96) Negative Predictive Value 59% (42-74) 79% (54-93) 74% (53-88) Positive likelihood ratio 5.27 ( ) 2.13 ( ) 3.49 ( ) Negative likelihood ratio 0.26 ( ) 0.1 ( ) 0.13 ( ) Accuracy 80% 84% 86% *Paramedic diagnosis For the retrospective (January to December 2000) and prospective (September 2002 to August 2003) examined, 79% and 82% of all confirmed strokes were admitted by ambulance, respectively, with 41.5% and 48% calling the emergency number within 2 hrs of onset. For the MASS paramedics sensitivity improved from 78% (95%CI 63 to 88%) to 94% (95%CI 86 to 98%) (p=006). Stroke diagnosis in the control paramedic group did not change significantly (78 vs 80&; NS). For the MASS paramedics the sensitivity of stroke diagnosis was greater when the MASS tool was used compared with strokes for which there was no documented assessment (95 vs 70%; p=0.001).

12 Kidwell CS, Starkman S, Eckstein M et al. Identifying stroke in the field. Prospective validation of the Los Angeles prehospital stroke screen (LAPSS). Stroke. 2000; 31(1): Ref ID 1047 Prospective cohort II+ USA N=446 Patients with a neurologically relevant symptom: mean age 63.3 yrs, 48% female Target stroke patients: mean age 77.7yrs, 50% female, median duration from symptom onset to time of paramedic examination was 75 mins Los Angeles Prehospital Stroke Screen (LAPSS) consists of four history items (age >45 yrs, history of seizures or epilepsy absent, symptom duration less than 24 hrs, as baseline, patients is not wheelchair bound or bedridden) One blinded author reviewed emergency department charts, recorded final emergency department discharge diagnoses, and confirmed absence or presence of potential stroke symptoms. 7 months (data collection) Actual test performance (rater performance) Instrument performance (to correct for documentation errors) National Stroke Association and American Heart Association 60 minute LAPSS-based stroke training to educate paramedics in the use of the LAPSS as well as general stroke care knowledge. They were shown 5 video vignettes of paramedics performing the

13 LAPSS examination on 3 stroke patients, 1 stroke mimics and 1 normal subject. A certification tape was shown requiring paramedics to complete the LAPSS examination on each vignette. Patients were transported by a paramedic vehicle involved in the study. Effect *Diagnostic accuracy Of 1298 total paramedic runs, 49 patients had a final diagnosis of ischaemic stroke, intracerebral haemorrhage or TIA and of these, 36 were target stroke patients. Of the 446 patients with a neurologically relevant symptom, LAPSS forms were completed on 206. For the 36 target stroke patients, LAPSS forms were completed on 34. Sensitivity Specificity Accuracy Positive Likelihood Ratio Negative Likelihood Ratio Rater performance 91 (76-98) 97 (93-99) 96 (92-98) 31 (16-147) 0.09 (0-0.21) (LAPSS runs) Rater performance (all 86 (70-95) 99 (99-100) 99 (99-100) 217 ( ) 0.14 ( ) runs) Instrument performance 91 (76-98) 99 (97-99) 99.6 (99-100) 97 (84-99) 99.7 (99-100)

14 (LAPSS runs) Paramedic performance when completing the LAPSS gave the following: Sensitivity 91% (95%CI 76 to 98%; specificity 97% (93 to 99%); PPV 86% (70 to 95%) (corrected for documentation error 97% (84 to 99%) and NPV 98% (95 to 99%) Kothari RU, Pancioli A, Liu T et al. Cincinnati Prehospital Stroke Scale: reproducibility and validity.[see comment]. Annals of Emergency Medicine. 1999; 33(4): Ref ID 153 Prospective cohort II+ USA N=171 Patients identified in the emergency department with or without a final diagnosis of stroke. An attempt was made to identify patients with chief complaints that were suggestive or stroke or other diseases that could be mistaken for stroke. In addition patients were recruited from inpatient neurology services. Stroke patients The Cincinnati Prehospital Stroke Scale (CPSS) was derived from a simplification of the 15-item NIH stroke scale. The CPSS evaluates the presence or absence of facial palsy, asymmetric arm weakness, and speech abnormalities in potential stroke patients. Paramedics (N=17) and Emergency Medical Technician (EMTs) (N=7) were blinded to all patients One of two physicians certified in the use of the NIH Stroke Scale performed the CPSS Reproducibility Correlations between physicians and prehospital providers Sensitivity Specificity Not stated Genentech

15 (N=38): 14 (37%) had deficits involving the posterior circulation. 32 patients (18.7%) had nonstroke neurological disorders or altered mental status; 7 (21%) of these 32 patients had at least one abnormality on the CPSS. The groups were wellmatched except nonstroke patients were significantly younger than stroke patients (mean difference 6.7 yrs, 95%CI 11.7 to 1.7 yrs). information and applied the CPSS.

16 Effect *Reproducibility There was high reproducibility among pre-hospital care providers for total score (r 1,0.89; 95%CI 0.87 to 0.92) and for each scale item: arm weakness (r 1,0.91; 95%CI 0.88 to 0.93; speech (r1 0.84; 95%CI 0.80 to 0.87); and facial droop (r1 0.75; 95%CI 0.69 to 0.80). *Physicians vs prehospital providers There was a high correlation between the physicans total scores and the prehospital providers (r ; 95%CI 0.89 to 0.93) with no difference related to level of training (r1 for paramedics 0.88; 95%CI 0.85 to 0.91; for EMTs 0.85; 95%CI 0.81 to 0.89). Agreement on scoring on specific items between physicians and pre-hospital personnel was high for all three items arm weakness (r ), speech (r ), and facial droop (r ). There were no differences in terms of level of training (NS). *Diagnostic accuracy Presence of a single abnormality on the CPSS had a sensitivity of 66% and a specificity of 87% in identifying a patient with stroke when scored by the physican and 59% and 89% respectively when scored by prehospital providers. Of the 13 patients with stroke who were not identified by an abnormality on the prehospital stroke scale, 10 had posterior circulation stroke. Physicians Prehospital care providers No. of abnormalities Sensitivity (95%CI) Specificity (95%CI) Sensitivity (95%CI) Specificity (95%CI) 1 66 (49-80) 87 (80-92) 59 (51-67) 88 (86-91) 2 26 (14-43) 95 (90-98) 27 (21-35) 96 (94-97) 3 11 (3-26) 99 (95-100) 13 (8-20) 98 (96-99) The CPSS correctly identified 21/24 patients with anterior circulation stroke (sensitivity 87%; 95%CI 67 to 97%).