Screening for Suspected Stroke in the Pre-Hospital Setting.
Date First Published:
June 5, 2020
Last Updated:
July 28, 2020
Report by:
Captain Ian Gibbons, General Duties Medical Officer (Royal Army Medical Corps)
Search checked by:
Flight Lieutenant Owen Williams, Royal Army Medical Corps
Three-Part Question:
In [patients with suspected stroke in the pre-hospital setting] is [the FAST screening tool more accurate than the ROSIER tool] at [correctly identifying stroke]?
Clinical Scenario:
You are tasked to assess a 42-year-old solider who has developed sudden onset slurred speech and weakness in the right arm whilst on exercise. The National Institute for Health and Care Excellence (NICE) guidelines recommend the use of a validated stroke screening tool such as “FAST (Face Arm Speech Test)” in the pre-hospital setting, or “ROSIER (Recognition of Stroke in the Emergency Room)” in the hospital setting. Recognising different screening tools are recommended between settings, you wonder whether there is a difference in accuracy between the screening tools.
Search Strategy:
The Health Database Advanced Search interface was used to search the PubMed, EMBASE and Medline databases. The search terms used were: “prehospital”, “pre-hospital”, “stroke screening”, “CVA screening”, “cerebrovascular accident screening”, “ROSIER”, “recognition of stroke in the emergency room” and “FAST”.
Outcome:
1,233 papers were found and screened, of which 17 were potentially relevant. Following full text review of these papers, 5 were chosen for inclusion, consisting of 4 systematic reviews and 1 retrospective study.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Pre-hospital stroke scales as screening tools for early identification of stroke and transient ischemic attack (Review). Cochrane database of systematic reviews 2019 Zhelev et al. 2019 | Non-comatose, no trauma adults presenting within 24 hours of a suspected TIA or stroke, who were assessed with a stroke recognition scale in a pre-hospital or Emergency Room setting | Cochrane review | Sensitivity and specificity in the pre-hospital and hospital settings | No statistically significant difference in sensitivities and specificities between ROSIER and FAST in the ER. ROSIER: 2895 patients included Sensitivity= 84%- 91% Specificity= 18%-93% FAST: 1894 patients included Sensitivity 64%-97% Specificity | No comparisons made between FAST and ROSIER in the field pre-hospital environment. Small number of studies per test per setting. Heterogeneity between studies. High risk of bias for two of the FAST studies. |
| Diagnostic accuracy of clinical tools for assessment of acute stroke: a systematic review. Antipova et al. 2019 | Adults presenting with ischaemic stroke, acute haemorrhagic stroke, stroke mimicking conditions and transient ischaemic attack in the pre-hospital and hospital settings | Systematic review | Sensitivity, specificity, PPV, NPV | ROSIER: Sensitivity= 79% Specificity= 76% PPV= 61% NPV= 88% FAST: Sensitivity= 84% Specificity= 44% PPV= 32 % NPV= 90% | Only focused on large vessel occlusion, excluding more minor strokes. No differentiation between use of the tools in the pre-hospital or hospital setting |
| A systematic review of stroke recognition instruments in hospital and prehospital settings. Rudd et al. 2016 | Adults presenting with suspected stroke, assessed with a stroke recognition tool prospectively applied face-to-face by a clinician | Systematic review | Sensitivity, specificity, PPV, NPV | ROSIER: 2445 patients included. Sensitivity 83%-97% Specificity 18%-93% PPV 62%-94%) NPV 33%-88%. FAST: 1841 patients included Sensitivity 79%-97% Specificity 13%-88% PPV 62%-89% NPV 48%-93% | Heterogenous study design. Wide variation in the sensitivity and specificity of each tool between studies. Limited recognition of false negative rates, especially in studies where test-negative patients were not transported to the study centre. |
| Prehospital stroke scales in urban environments. Brandler et al. 2014 | Adults presenting with suspected stroke, who were assessed by a paramedic or emergency medical technician, with the use of a pre-hospital stroke scale | Systematic review | Stroke prevalence, sensitivity, specificity, LR + and LR- of each tool. | ROSIER: 295 patients included from 1 study Sensitivity= 97% Specificity=18% LR+= 1.17 LR-= 0.19 FAST: 295 patients included from 1 study Sensitivity= 97% Specificity= 13% LR+= 1.10 LR-= 0.26 | Large confidence intervals. Only 1 study compared FAST and ROSIER |
| Comparison of stroke recognition and stroke severity scores for stroke detection in a single cohort. Purrucker et al 2015 | All patients presenting with potential stroke, attended by EMS paramedics and emergency physicians in one emergency department | Retrospective study | Sensitivity, specificity, PPRV, NPV | ROSIER: Sensitivity= 80% (73%-85%) Specificity= 79% (75-83%) PPV= 59% (53%-66%) NPV 91% (88%-94%) FAST: Sensitivity 85% (78-90%) Specificity 68% (64-72%) PPV= 50% (44%-55%) NPV 92% (89%- 95%) | Retrospective study design |
References:
- Zhelev et al. . Pre-hospital stroke scales as screening tools for early identification of stroke and transient ischemic attack (Review). Cochrane database of systematic reviews 2019
- Antipova et al. . Diagnostic accuracy of clinical tools for assessment of acute stroke: a systematic review.
- Rudd et al.. A systematic review of stroke recognition instruments in hospital and prehospital settings.
- Brandler et al. . Prehospital stroke scales in urban environments.
- Purrucker et al. Comparison of stroke recognition and stroke severity scores for stroke detection in a single cohort.