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Step 2B: Critically assess each article/source in terms of research design and methods.Was the study well executed?Suggested criteria appear in the table below. Assess design and methods and provide an overallrating. Ratings apply within each Level; a Level 1 study can be excellent or poor as a clinical trial, just as a Level 6 study could be

excellent or poor as an animal study. Where applicable, please use a superscripted code (shown below) to categorize the primary

endpoint of each study. For more detailed explanations please see attached assessment form.

Component of

Study and Rating Excellent Good Fair Poor Unsatisfactory

Design Highly appropriatesample or model,

randomized, proper

controls

More thanadequate design;

minimally biased

Adequate, design,but possibly biased Small or clearlybiased population

or model

Anecdotal, nocontrols, off target

end-points

Methods Outstanding

accuracy, precision,

and data collection

in its class

More than

adequate in its

class

Adequate under the

circumstances

Weakly defensible

in its class,

limited data or

measures

Not defensible in

its class,

insufficient data or

measures

A = Return of spontaneous circulation C = Survival to hospital discharge E = Other endpoint

B = Survival of event D = Intact neurological survival

Step 2C: Determine the direction of the results and the statistics: supportive? neutral? opposed?

DIRECTION of studyby results & statistics: SUPPORT the proposal NEUTRAL OPPOSE the proposal

Results

Outcome of proposed guideline

superior, to a clinically important

degree, to current approaches


no different from current

approach


inferior to current approach

Step 2D: Cross-tabulate assessed studies by a) level, b) quality and c)direction (ie, supporting or neutral/

opposing); combine and summarize. Exclude the Poorand Unsatisfactory studies. Sort theExcellent, Good, and Fairqualitystudies by bothLevel and Quality of evidence, andDirection of supportin the summary grids below. Use citation marker (e.g. author/

date/source). In theNeutral or Opposing grid use bold font for Opposing studies to distinguish them from merely neutral studies.

Where applicable, please use a superscripted code (shown below) to categorize the primary endpoint of each study.

Supporting EvidenceThe use of prehospital stroke scales improves the sensitivity and specificity of EMS providers ability to

recognize stroke patients compared to providers not using a stroke scale.

Excellent

GoodKidwell00 - E

Qualityo

fEvidence

Fair Kothari97-EKothari99-E

Zweifler98-EKidwell98 EHarbison03-E

1 2 3 4 5 6 7 8

Level of EvidenceA = Return of spontaneous circulation C = Survival to hospital discharge E = Other endpoint


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is currently required in the their curriculum. It is probably helpful for paramedics to be given a tool for

the recognition of stroke in the field like the CPSS or LAPSS. However, additional testing is still needed

before any scale can be given a class 1a recommendation. Testing of these two scales in the field is

limited and was only conducted with the LAPSS, which produced a sensitivity of 86%. Although both

test preformed well when used by a physician in the hospital. Further, study is needed but clearly the

scales are not harmful and may improve stroke recognition (class IIB).

Review: There is a need for prompt recognition by EMS providers that a patient is suffering a stroke.

Currently, this is needed so that providers will expeditiously transport stroke patients to an appropriatereceiving facility, which has been notified of the patients imminent arrival so that the patient receives prompt

treatment within the narrow therapeutic window. In the future, this early recognition may also be necessary so

that EMS providers may provide prompt interventions prior to arrival at a receiving facility.

A recent survey of a random sample of EMS providers that belong to the National Registry found thatproviders were able to identify stroke signs and symptoms but were not familiar with treatments.(Crocco,

Kothari et al. 1999) Ellison and colleagues through a retrospective chart review, determined providers ability

to recognize stroke and found that without the use of a formal scale or any special training paramedics had asensitivity of 64% (95%CI 54-73%), specificity 63% (95%CI 52-74%) and negative predictive value of 57%

(95%CI 46-67%) for recognizing a stroke patient using the emergency physicians diagnosis as the gold

standard. (Ellison, Gratton et al. 2004) In an abstract Kothari et al found that EMS providers had a sensitivity

of 41.4% (95% CI 34-49), a specificity of 99.9% (95%CI 99.8-100), a positive predictive value of 97% and anegative predictive value of 98.5%.(Kothari, Pio et al. 1999) An additional study that did not provide special

training, conducted by Smith and colleagues found similar results, they demonstrated that normally trained

paramedics had a sensitivity of 61% and a positive predictive value of 77% for identifying patients who werehaving a stroke.(Smith, Isaacs et al. 1998) Finally, Wojner and colleagues in a prospective study found that

paramedics had a sensitivity of 66% and specificity of 98%.(Wojner, Morgenstern et al. 2003)

Smith and colleagues then measured paramedics ability to recognize stroke patients after 4 hours oftraining with the NIH stroke scale compared to paramedics who had not been trained.(Smith, Corry et al. 1999)

They did not ask the paramedics to use a scale in the field but to make an assessment of whether the patienthad had a stroke or not. They found a sensitivity of 91% for the trained and 90% for the untrained paramedics

and a positive predictive value of 64% for the trained and 68% for the untrained. However, they suspected

there was some crossover of the information since the trained and untrained paramedics were able to worktogether. In a similar study Zweifler and colleagues found that prior to education paramedics had a sensitivity

of 91%, but after training and provision of a scale for use in the field, that was created for this study, there was

a non-significant increase in sensitivity to 97%.(Zweifler, York et al. 1998) Similarly the positive predictivevalue increased from 66% to 76%.

There are primarily two stroke scales designed for use in the prehospital setting. The Los Angeles

Prehospital Stroke Scale (LAPSS), includes patient history as well as stroke signs and symptoms to avoid over-

diagnosis of stroke. The LAPSS was developed by Kidwell and colleagues, who first applied the scale topatients enrolled in a clinical trial.(Kidwell, Saver et al. 1998) They found that when physicians used the scale

retrospectively it had a 92% sensitivity, 93% if they only looked at patients with ischemic stroke. Kidwell and

colleagues later conducted a prospective study of paramedics using the LAPSS after 1 hour of training and

perfect completion of 5 practice vignettes.(Kidwell, Starkman et al. 2000) When the paramedics findingswere compared to discharge diagnosis they had a sensitivity of 86% (95%CI 70-95), specificity of 99% (95%

CI 99-100), positive predictive value of 86% (95% CI 70-95), and a negative predictive value of 99% (99-100).The authors also calculated improved values when they changed what they considered to be documentation

errors by the paramedics.

The second major prehospital stroke scale is the Cincinnati Prehospital Stroke Scale (CPSS) which was

originally called the out-of-hospital NIH stroke scale because it uses three questions from the NIH scale.Kothari and colleagues demonstrated that when used prospectively by physicians this scale had 100%

sensitivity and 88% specificity.(Kothari, Hall et al. 1997) Further, when they had paramedics see potential

stroke patients with physicians in the emergency department, after being refreshed on the CPSS criteria


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immediately before seeing the patient, the inter-rater reliability was 0.89 (95%CI .87-.93) and there was good

agreement with the gold standard 0.92 (95%CI .89 -.93).(Kothari, Pancioli et al. 1999) The paramedicssensitivity was 59% (95%CI 51-67) and specificity was 88% (95%CI 86-91). However, when they looked

only at the ability to identify an anterior circulation strokes the sensitivity rose to 87.5% (95%CI 67-97).

Some alternative scales do exist such as the FAST, the shortened NIH Stroke Scale, and MEND scale.The FAST scale, created by Harbison and colleagues and used in their EMS system, appears to be very similar

to the CPSS without a set phrase for testing speech. Harbison et al. reported that it had a positive predictive

value of 78% (95% CI72-78) when they looked at the accuracy of paramedics bringing patients directly to astroke facility, sensitivity and specificity could not be calculated.(Harbison, Hossain et al. 2003) The shortened

NIH stroke scale was created using a derivation and a validation data set from a clinical trial.(Tirschwell,

Longstreth et al. 2002) Its validity was tested for measuring severity not for detecting stroke and no other

studies were identified that used this scale. The MEND scale does not appear to have been tested and wasdescribed only in a non-peer reviewed EMS trade journal.

Given the current state of stroke care it is most important that EMS have a high sensitivity for

identifying stroke patients. This is because it is most important that EMS recognize a patient is possiblyhaving a stroke, alert the receiving facility of that possibility and provide rapid transport so that the patient has

the greatest chance of receiving treatment within the recommended therapeutic window. When paramedics are

given standard training their sensitivity ranges from 41 - 66%. With intensive specialized training this

increases to between 90 and 97%. Therefore, it is important that paramedics be provided with training in therecognition of stroke patients beyond what is currently required in the their curriculum. It is probably helpful

for paramedics to be given a tool for the recognition of stroke in the field like the CPSS or LAPSS. However,

additional testing is still needed before any scale can be given a class 1a recommendation. Testing of thesetwo scales in the field is limited and was only conducted with the LAPSS, which produced a sensitivity of

86%. Although both test preformed well when used by a physician in the hospital. Further, study is needed

but clearly the scales are not harmful and may improve stroke recognition (class IIB).

Preliminary draft/outline/bullet points of Guidelines revision: Include points you think are important for inclusion by the person assigned to

write this section. Use extra pages if necessary.

Attachments:

Printed (paper) bibliography; and on diskette using a reference manager. It is recommended that the bibliography be printed in annotatedformat. This will include the article abstract and any notes you would like to make providing specific comments on the quality,

methodology and/or conclusions of the study.

Key figures or tables from evidence-based analysis

Full hard copies of most critical cited papers


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Citation List

Citation Marker Full Citation*

Crocco99

Ellison04

Included papers:

Crocco, T. J., R. U. Kothari, et al. (1999). "A nationwide prehospital strokesurvey." Prehosp Emerg Care 3(3): 201-206.

Comment: LOE 5, fair, neutralThis study found that EMS providers know the signs and symptoms of stroke but not the

treatment. This study was a survey of a random sample EMS providers who were

members of the national registry. The response rate was poor (36%).OBJECTIVES: To identify deficiencies in stroke knowledge amongprehospital providers. METHODS: A nationwide multiple-choice survey

was sent to 689 paramedics (EMT-Ps) and 294 advanced EMTs (EMT-Is)

from a random selection of the National Registry of Emergency Medical

Technicians database. Of the 23 questions, five addressed demographicinformation, four quantity of training, five general knowledge, 6 and sevenmanagement, and two open-ended questions addressed the signs,

symptoms, and risk factors of stroke. The EMT-P and EMT-I answers were

compared using chi-square analysis or Fisher's exact test. RESULTS: Ofthe 355 (36%) respondents, 256 (72%) were EMT-Ps and 99 (28%) wereEMT-Is. Virtually all the EMT-Ps (99%) and EMT-Is (98%) knew that a

stroke injures the brain, but only 199 (78%) of the EMT-Ps and 47 (47%)

of the EMT-Is correctly defined a transient ischemic attack (TIA) (p & lt;0.001). Slurred speech, weakness/ paralysis, and altered mental status were

the three most commonly cited symptoms of stroke by both groups. The

EMT-Ps were more likely to recognize that dextrose is potentially harmfulto stroke patients [EMT-P = 216 (85%), EMT-I = 71 (72%), p = 0.005];

169 (66%) of the EMT-Ps and 75 (76%) of the EMT-Is felt that elevated

blood pressures should be lowered in the prehospital setting. Only 93

(36%) of the EMT-Ps and 22 (22%) of the EMT-Is knew that tissueplasminogen activator (tPA) must be given within three hours of symptom

onset (p = 0.01). CONCLUSION: Most EMS providers are knowledgeable

about the symptoms of stroke but are unaware of the therapeutic windowfor thrombolysis and the recommended avoidance of prehospital blood

pressure reduction. In addition, further education is needed regarding TIAs.

Ellison, S. R., M. C. Gratton, et al. (2004). "Prehospital dispatch assessment of

stroke." Mo Med 101(1): 64-6.

Comment: LOE 5, fair, opposingEllison and colleagues looked at providers ability to recognize stroke through a

retrospective chart review and found that without the use of a formal scale paramedics hada sensitivity of 64% (95%CI 54-73%), specificity 63% (95%CI 52-74%) and negativepredictive value of 57% (95%CI 46-67%) using emergency physician diagnosis as the

gold standard. No special training was given to the paramedics beyond what they got

during standard training.This study is to determine the assessment accuracy for the diagnosis of

stroke by EMS dispatchers and paramedics compared to emergencyphysicians (EPs). Of the 191 patients who met inclusion criteria,

dispatchers assessed 133 as having a stroke; EPs agreed in 67 (50%) cases.

Paramedics assessed 100 patients as having stroke; EPs agreed in 70 (70%)cases. Dispatcher and paramedic sensitivity for diagnosing stroke was 61%


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Harbison03

Kidwell98

and 64%, respectively; specificity was 20% and 63% respectively.

Sensitivity for the detection of acute stroke was nearly identical between

EMS dispatchers and on-scene paramedics; overall agreement with

emergency physician diagnosis was moderate.

Harbison, J., O. Hossain, et al. (2003). "Diagnostic accuracy of stroke referrals

from primary care, emergency room physicians, and ambulance staff using theface arm speech test." Stroke 34(1): 71-6.

Comment: LOE 5, fair, supportingThe FAST exam, created by Harbison and colleagues and used in their EMS system,

appears to be very similar to the CPSS without a set phrase for testing speech. Harbison etal. reported that it had a positive predictive value of 78% (95% CI72-78) when they

looked at the accuracy of paramedics bringing patients directly to a stroke facility,

sensitivity and specificity could not be calculated.

BACKGROUND AND PURPOSE: Timely referral of appropriate patientsto acute stroke units is necessary for effective provision of skilled care. We

compared the characteristics of referrals with suspected stroke to an

academic acute stroke unit via 3 primary referral routes: ambulance

paramedics using a rapid ambulance protocol and stroke recognitioninstrument, the Face Arm Speech Test; primary care doctors (PCDs); and

emergency room (ER) referrals. METHODS: Patient characteristics, final

diagnosis, and admission delay were recorded in all suspected acute strokereferrals in a 6-month period. RESULTS: Four hundred eighty-seven

patients (356 strokes/transient ischemic attacks) were admitted by the 3

routes: 178 by ambulance, 216 by PCDs, and 93 through the ER. Theproportion of non-strokes admitted by each route was similar (23%, 29%,

and 29%, respectively). Ambulance paramedics' stroke diagnosis was

correct in 144 of 183 (79%) stroke patients who initially presented to them.Thirty-nine of 66 strokes/transient ischemic attacks referred via ER were

taken there following initial ambulance assessment. Compared with PCDs,paramedics referred more total anterior circulation (39% versus 14%,

P


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Kidwell00

critical components of successful acute stroke treatment. This preliminary

study sought to demonstrate that a new prehospital screening instrument,

the Los Angeles Prehospital Stroke Screen (LAPSS), sensitively identifies

acute stroke patients. Further, the study evaluated the potential timesavings that could be achieved by paramedic administration of

neuroprotective agents in the field. METHODS: The authors designed a

simple stroke screening tool for use by prehospital personnel, emphasizingmotor deficits. They then tested instrument performance and time savings

retrospectively, employing data from patients enrolled within six hours of

symptom onset in randomized stroke trials at three university-associatedparamedic receiving hospitals. RESULTS: Fifty of 83 patients enrolled in

hyperacute stroke trials arrived by ambulance, including 41 with ischemic

infarcts and seven with hemorrhages. Of the 41 with acute ischemic stroke,

38 (93%) would have been accurately identified by the LAPSS. For these38 patients, 1 hour and 50 minutes would have been saved had

neuroprotective drug been administered by paramedics at the time of

transport vs. the actual time of study agent administration in the emergencydepartment. CONCLUSIONS: The LAPSS sensitively identifies

ambulance-arriving acute stroke patients, and a substantial time savings

will potentially occur if neuroprotective agents are administered byparamedics in the field. The LAPSS is a promising tool that may enable

paramedic recognition of stroke with a high degree of sensitivity and

simplicity in a short period of time.

Kidwell, C. S., S. Starkman, et al. (2000). "Identifying stroke in the field.

Prospective validation of the Los Angeles prehospital stroke screen (LAPSS)."Stroke 31(1): 71-76.

Comment: LOE 5, Good, supportingKidwell and colleagues conducted a prospective study of paramedics using the LAPSS

after 1 hour of training and perfect completion of 5 practice vignettes. When theparamedics findings were compared to discharge diagnosis they had a sensitivity of 86%

(95%CI 70-95), specificity of 99% (95% CI 99-100), positive predictive value of 86%

(95% CI 70-95), and a negative predictive value of 99% (99-100). The authors also

calculated improved values when they changed what they considered to documentationerrors by the paramedics

BACKGROUND AND PURPOSE: Reliable identification of stroke

patients in the field by prehospital personnel could expedite delivery of

acute stroke therapy. The Los Angeles Prehospital Stroke Screen (LAPSS)is a 1-page instrument designed to allow prehospital personnel to rapidly

identify acute stroke patients in the field. We performed a prospective, in-

the-field validation study of the LAPSS. METHODS: Paramedics assignedto 3 University of California at Los Angeles-based advanced life support

units were trained and certified in use of the LAPSS. Over 7 months,

paramedics completed the LAPSS on noncomatose, nontrauma patientswith complaints suggestive of neurological disease. LAPSS form stroke

identification results were compared with emergency department and final

hospital discharge diagnoses. Sensitivity, specificity, positive predictivevalue, negative predictive value, accuracy, and likelihood ratios were

calculated for LAPSS identification of ischemic stroke, currently

symptomatic transient ischemic attack, and intracerebral hemorrhage.

RESULTS: Of a total of 1298 runs, 34% were for nontraumatic,


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Kothari97

Kothari99

noncomatose neurologically relevant complaints. Thirty-six of these

patients (3% of all transports) had a final diagnosis of acute symptomatic

cerebrovascular disease (21 ischemic strokes, 7 transient ischemic attacks,

and 8 intracerebral hemorrhages). LAPSS forms were completed on 206patients. Paramedic performance when completing the LAPSS

demonstrated sensitivity of 91% (95% CI, 76% to 98%), specificity of 97%

(95% CI, 93% to 99%), positive predictive value of 86% (95% CI, 70% to95%), and negative predictive value of 98% (95% CI, 95% to 99%). With

correction for the 4 documentation errors, positive predictive value

increased to 97% (95% CI, 84% to 99%). CONCLUSIONS: The LAPSSallows prehospital personnel to identify patients with acute cerebral

ischemia and intracerebral hemorrhage with a high degree of sensitivity

and specificity.

Kothari, R., K. Hall, et al. (1997). "Early stroke recognition: developing an out-of-

hospital NIH Stroke Scale." Acad Emerg Med 4(10): 986-990.

Comment: LOE 3, Fair, opposingDescribes development of the Cincinnati stroke scale. They demonstrated that

when used by pa physician it has a sensitivity of 100% and a specificity of 88%.

The scale uses 3 questions form the NIH stroke scale.OBJECTIVE: To develop an abbreviated and practical neurologic scale

that could assist emergency medical services or triage personnel in

identifying patients with stroke. METHODS: A prospective, observational,cohort study was performed at university-based EDs. Participants were 74

patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12- hour shifts in the ED. Scores

on the NIH Stroke Scale were obtained for all patients by physicians. Items

of this scale were modified and recoded to a binomial (normal or

abnormal) scale. Serial univariate analyses using chi 2 were performed to

rank items. Recursive partitioning was then performed to develop thedecision rule for predicting the presence of stroke. RESULTS: Three items

identified 100% of patients with stroke: facial palsy, motor arm, anddysarthria. An Abbreviated NIH Stroke Scale based on these items had a

sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital

NIH Stroke Scale consisting of facial palsy, motor arm, and a combinationof dysarthria and best language items (abnormal speech) had a sensitivity

of 100% and a specificity of 88%. CONCLUSION: Using the derivation

data set, a proposed Out-of-hospital NIH Stroke Scale had a highsensitivity and specificity for identifying patients with stroke when

performed by physicians in this group of 299 ED patients. Prospective

studies of other health care professionals using the scale in the out-of-hospital arena are needed.

Kothari, R. U., A. Pancioli, et al. (1999). "Cincinnati Prehospital Stroke Scale:

reproducibility and validity." Ann Emerg Med 33(4): 373-378.

Comment: LOE 3, fair, supportingKothari et al had paramedics see potential stroke patients with physicians in the

emergency department. After being refreshed on the CPSS criteria immediately before


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Smith98

were transported to two university hospitals were reviewed. Subjects were

identified by paramedic assessment as stroke/transient ischemic attack

(TIA) and/or final hospital discharge diagnosis of stroke/TIA after detailed

chart review. Sensitivity and PPV for paramedic identification of strokewere calculated. RESULTS: During the prospective six-month phase, 84

confirmed stroke patients were transported to the target hospitals. Of the 32

who were transported by trained paramedics, all but three were identifiedas having stroke/TIA, resulting in a sensitivity of 91%. This is significantly

higher than the 61% previously found (p=0.01). Nontrained paramedics

also increased their sensitivity to 90%. Thirty-eight false-positive patientswere identified, resulting in PPVs of 64% for trained paramedics and 69%

for all other paramedics. CONCLUSIONS: Institution of an educational

stroke program was associated with a significant increase in sensitivity in

stroke identification by the paramedics; however, educational influencesoutside this training program may have contributed to the increased

sensitivity. Better education for paramedics, combined with rapid response

to stroke victims once identified, may result in improved care for victims ofacute stroke.

Smith, W. S., M. Isaacs, et al. (1998). "Accuracy of paramedic identification ofstroke and transient ischemic attack in the field." Prehosp Emerg Care 2(3): 170-

175.

Comment: LOE 5, fair, opposingThis study did not provide special training to paramedics. They demonstrated that

normally trained paramedics had a sensitivity of 61% and a positive predictive value of

77% for identifying patients who were having a stroke.PURPOSE: To determine the accuracy of acute stroke identification by

paramedics in an urban emergency medical services system. METHODS:Retrospective chart review of all patient encounters by paramedics

resulting in transport to two university hospitals during a six-month period.Subjects were identified by paramedic coding of stroke/transient ischemicattach (TIA) or final hospital discharge ICD- 9 diagnosis of acute stroke

and TIA. The sensitivity and positive predictive value for paramedic

identification of stroke were calculated, and the time intervals fromsymptom onset to various points along the patients' prehospital and hospital

courses were identified. RESULTS: Ninety-six patients were identified, of

whom 81 met the diagnosis of acute stroke or TIA. Paramedics identified

49 of these 81 patients (sensitivity 61%). Fifteen patients were identifiedby paramedics as having a stroke when the patient ultimately had a

different diagnosis (positive predictive value 77%) Patients or their

families waited on average 2.5 +/- 3.6 (SD) hours before accessing 911,and a mean of 5.1 +/- 4.0 (SD) hours elapsed from symptom onset until

head imaging studies were obtained. CONCLUSION: Paramedics in San

Francisco County were correct three-fourths of the time when theirdocumentation listed patients as having stroke/TIA. However, they did not

identify 39% of stroke victims, a patient population who may benefit from

urgent therapy. A substantial period elapses before stroke victims access

911. This highlights the need to develop an educational program for thecommunity at risk for stroke, and another for paramedics directed toward

more accurate identification of acute stroke victims.


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Wojner03

Zweifler98

Wojner, A. W., L. Morgenstern, et al. (2003). "Paramedic and emergency

department care of stroke: baseline data from a citywide performanceimprovement study." Am J Crit Care 12(5): 411-7.

Comment: LOE 5, fair, opposingWojner and colleagues in a prospective study found that paramedics had a sensitivity of

66% and specificity of 98% without prior education or use of a stroke scale.BACKGROUND: Rapid diagnosis and transport by paramedics andefficient, effective emergency management are essential to improving care

of acute stroke patients. OBJECTIVES: To measure the performance of

paramedics and emergency departments providing care for patients with

suspected acute stroke. METHODS: Two stroke centers and 4 otherhospitals where most patients with acute stroke in Houston, Tex, are

admitted participated. Hospital and paramedic performance data were

collected prospectively on 446 patients with suspected acute stroketransported by paramedics between September 1999 and February 2000.

RESULTS: Paramedics had a sensitivity of 66%, specificity of 98%, and

overall accuracy of 72% in diagnosing stroke. For patients with suspectedstroke, 58.5% arrived in the emergency department within 120 minutes of

symptom onset; in confirmed cases, that percentage was 67%. Mean total

transport time was 42.2 minutes and was significantly longer (P < .001) to

inner-city hospitals (44 minutes) than to suburban, community-basedcenters (39 minutes). Door to computed tomography times were

significantly (P < .001) shorter for the 2 stroke centers than the other

hospitals. Overall thrombolysis treatment rate among patients withconfirmed ischemic stroke was 7.4% (range, 0-19.4%); treatment rates at

the 2 stroke centers were 5.9% and 19.4%. CONCLUSIONS: More than

half of patients with suspected stroke arrive at hospitals while thrombolytic

treatment is still feasible. Although the current rate for thrombolytictreatment in Houston exceeds the national rate, performance of paramedics

and hospitals in treating acute stroke can be improved by increasingefficiency and standardizing medical practices.

Zweifler, R. M., D. York, et al. (1998). "Accuracy of Paramedic Diagnosis of

Stroke." Journal of Stroke and Cerebrovascular Disease 7(6): 446-8.

Comment: LOE 4, fair, supportingIn this study Zweifler and colleagues found that prior to education, paramedics had a

sensitivity of 91% for identifying stroke, but after training and provision of a scale for use

in the field, there was a non-significant increase in sensitivity to 97%. The positive

predictive value increased from 66% to 76%.No abstract available

Excluded References

Alberts, M. J., A. Perry, et al. (1992). "Effects of public and professional education

on reducing the delay in presentation and referral of stroke patients." Stroke 23(3):352-356.

Comment: This article is about patient and provider education. To decrease


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presentation time they recommend provider education but do not describe what

they did or test it.

BACKGROUND AND PURPOSE: Several emerging stroke therapies

require patients to be treated within several hours of symptom onset. Paststudies have documented a significant delay between symptom onset and

hospital presentation. As part of an experimental treatment study using

tissue-type plasminogen activator, we began a multifaceted program ofpublic and professional education to reduce the delay in presentation and

referral of acute stroke patients. METHODS: The educational efforts

focused on improving the recognition of stroke symptoms, the studyenrollment criteria, and the need for rapid treatment of stroke patients. This

program included 1) interviews on television and radio, 2) newspaper

articles, 3) lectures to local and regional primary care and emergency

department physicians, 4) mailings to several thousand local physicians, 5)having neurologists on-call for referrals 24 hrs/day, and 6) use of the Duke

Life-Flight helicopter. RESULTS: Since starting our program, 139 of 159

(86%) patients with cerebral infarction presented primarily or were referredto our facility within 24 hours of symptom onset, compared with 70 of 187

(37%) before our educational efforts (p less than 0.00001). No significant

change was seen in patients with intracerebral hemorrhage (23 of 30+AD77%+BD within 24 hours after program, compared with 25 of 40

+AD63%+BD before educational efforts; p = 0.30). CONCLUSIONS:

These findings suggest that educational efforts aimed at the public andhealth professionals may increase recognition of stroke symptoms and

reduce the delay in presentation and referral of stroke patients.

Barsan, W. G., T. G. Brott, et al. (1993). "Time of hospital presentation in patients

with acute stroke." Arch Intern Med 153(22): 2558-2561.

Comment: This study shows that 47% of stroke patients use EMS for transport to

an emergency department and those who use EMS have the shortest time fromsymptom onset times to arrival at the hospital.

BACKGROUND: Stroke is a leading cause of death and disability in theUnited States. Although new treatments are being studied, most must be

given early in the course of stroke to be effective. This study was

performed to identify factors associated with early hospital arrival inpatients with stroke. METHODS: As part of the National Institute of

Neurologic Disorders and Stroke Tissue-Type Plasminogen Activator Pilot

Study, information from patients, patients' families, or, most commonly,the medical record was gathered on all patients presenting to the hospital

within 24 hours of the onset of stroke. A total of 14 hospitals participated.

Three were university hospitals, and 11 were community hospitals with andwithout university affiliation. The main outcome measure was the timefrom stroke onset to hospital arrival. RESULTS: Of 2099 patients

screened, adequate time data were available in 1159. Thirty-nine percent

presented to the hospital 90 minutes or less after symptom onset and 59%within 3 hours. Early hospital arrival after stroke was greatly influenced by

the type of first medical contact and, to a lesser degree, by the patient's

location at the time of the stroke and the time of the day at which the strokeoccurred. Hospital arrival was fastest in patients using 911 as their first

medical contact (mean, 155 minutes; median, 84 minutes) vs their personal


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physician (mean, 379 minutes; median, 270 minutes; P < .0001) or a study

hospital (mean, 333 minutes; median, 212 minutes; P < .0001). Time from

symptom onset to arrival was longer for patients having the stroke at night

compared with patients having a stroke in the morning (P < .05), in theafternoon (P < .01), or in the evening (P < .0001). Time to hospital arrival

was significantly longer for patients having the stroke at home than for

patients having the stroke at work (P < .01) or in an unknown place (P

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