Accuracy of clinical stroke scores for distinguishing stroke subtypes in resource poor settings: A systematic review of diagnostic test accuracy

Abstract

Background:Stroke is the second leading cause of death globally. Computerized tomography is used to distinguish between ischemic and hemorrhagic subtypes, but it is expensive and unavailable in low and middle income countries. Clinical stroke scores are proposed to differentiate between stroke subtypes but their reliability is unknown.Materials and Methods:We searched online databases for studies written in English and identified articles using predefined criteria. We considered studies in which the Siriraj, Guy's Hospital, Besson and Greek stroke scores were compared to computerized tomography as the reference standard. We calculated the pooled sensitivity and specificity of the clinical stroke scores using a bivariate mixed effects binomial regression model.Results:In meta-analysis, sensitivity and specificity for the Siriraj stroke score, were 0.69 (95% CI 0.62-0.75) and 0.83 (95% CI 0.75-0.88) for ischemic stroke and 0.65 (95% CI 0.56-0.73) and 0.88 (95% CI 0.83-0.91) for hemorrhagic stroke. For the Guy's hospital stroke score overall sensitivity and specificity were 0.70 (95% CI 0.53-0.83) and 0.79 (95% CI 0.68-0.87) for ischemic stroke and 0.54 (95% CI 0.42-0.66) and 0.89 (95% CI 0.83-0.94) for hemorrhagic stroke.Conclusions:Clinical stroke scores are not accurate enough for use in clinical or epidemiological settings. Computerized tomography is recommended for differentiating stroke subtypes. Larger studies using different patient populations are required for validation of clinical stroke scores.

Use of a Diagnostic Score to Prioritize Computed Tomographic (CT) Imaging for Patients Suspected of Ischemic Stroke Who May Benefit from Thrombolytic Therapy

“…This increases the predictive ability of the score to identify an ischemic stroke. For example, Mwita et al[ 10 ] in a systematic review reported consistently higher specificities of the SSS with a range from 65%–99% compared to its corresponding sensitivities in 18 validation studies. This is in agreement with our specificity findings.…”

“…The simplicity of this score and its practical application has been commended in several studies. [ 5 , 10 ] Nevertheless, we are aware that the recalibrated SSS may not be easily memorized or applied without a calculator. Future implementation of this score with a possible smartphone application will be useful.…”

“…Although several validation studies concluded that the scores were not sensitive enough in their detection of hemorrhage to replace CT imaging[ 9 – 11 ], there was a consistent trend of higher predictive abilities of the SSS to rule out a hemorrhagic stroke and thus, increases the chance of detecting an ischemic stroke. [ 10 ] Nevertheless, there remains a need to assess the ability of the SSS to identify ischemic stroke patients who are potentially eligible for thrombolytic therapy in the Malaysian population. Instead of replacing CT machines, the SSS is anticipated to act as a triage for prioritization of CT imaging.…”

Prehospital Identification of Stroke Subtypes in Chinese Rural Areas

“…In addition, a systematic meta-analysis by Mwita et al . [ 9 ] questioned the accuracy of clinical stroke scores for distinguishing stroke subtypes in resource-poor settings. To the best of our knowledge, none of these score systems have been validated in Chinese stroke patients.…”

Superiority of Siriraj Stroke Score Over Guy’s Hospital Score in Diagnosing Acute Hemorrhagic Stroke at Bedside

“…The sensitivity of Guy's Hospital stroke score for hemorrhage stroke is 96.4%, specificity is 100%, accuracy 97.1%, positive predictive value of 100% and negative predictive value 87.5%. Mwitaet al26 reported sensitivity for ischemic stroke ranged from 0.25 to 0.93 while specificity ranged from 0.50 to 0.97. Overall, sensitivity for the test was 0.7 (95% CI 0.53 0.83) and specificity was 0.79 (95% CI 0.68 0.87) for ischemic stroke.…”