Optimizing cutoff scores for the Barthel Index and the modified Rankin Scale for defining outcome in acute stroke trials

Background and Purpose - There is little agreement on how to assess outcome in acute stroke trials. Cutoff scores for the Barthel Index (BI) and modified Rankin Scale (mRS) are frequently arbitrarily chosen to dichotomize favorable and unfavorable outcome. We investigated sensitivity and specificity of BI cutoff scores in relation to the mRS to obtain the optimal corresponding BI and mRS scores. Methods - BI and mRS scores were collected from 1034 ischemic stroke patients. Sensitivity and specificity were calculated for BI cutoff scores from 45 to 100 in mRS score 1, 2, and 3 and were plotted in receiver operator characteristic (ROC) curves. Results - The cutoff scores for the BI with the highest sum of sensitivity and specificity were 95 (sensitivity 85.6%; specificity 91.7%), 90 (sensitivity 90.7%; specificity 88.1%), and 75 ( sensitivity 95.7%; specificity, 88.5%) for, respectively, mRS 1, 2, and 3. The area under the ROC curve was 0.933 in mRS 1, 0.960 in mRS 2, and 0.979 in mRS 3. Conclusions - The optimal cutoff scores for the BI were 95 for mRS 1, 90 for mRS 2, and 75 for mRS 3. For future acute stroke trials that assess stroke outcome with the BI and mRS, we recommend the use of these BI cutoff score(s) with the corresponding mRS cutoff score(s), to ensure the use of consistent and uniform end points

Timing of surgery for sciatica: subgroup analysis alongside a randomized trial

Surgery speeds up recovery for sciatica. Prolonged conservative care with surgery for those patients with persistent sciatica however, yields similar results at 1 year. To investigate whether baseline variables modify the difference in recovery rates between these treatment strategies, baseline data of 283 patients enrolled in a randomized trial, comparing early surgery with prolonged conservative care, were used to analyse effect modification of the allotted treatment strategy. For predictors shown to modify the effect of the treatment strategy, repeated measurement analyses with the Roland Disability Questionnaire and visual analogue scale pain as continuous outcomes were performed for every level of that predictor. Presumed predictive variables did not have any interaction with treatment, while “sciatica provoked by sitting” showed to be a significant effect modifier (P = 0.07). In a Cox model we estimated a hazard ratio (HR, surgery versus conservative) of 2.2 (95% CI 1.7–3.0) in favour of surgery when sciatica was provoked by sitting, while the HR was 1.3 (95% CI 0.8–2.2) when this sign was absent. The interaction effect is marginally significant (interactions are usually tested at the 10% level) but the patterns generated by the repeated measurement analyses of all primary outcomes are completely consistent with the inferred pattern from the survival analysis. Classical signs did not show any contribution as decision support tools in deciding when to operate for sciatica, whereas treatment effects of early surgery are emphasized when sciatica is provoked by sitting and negligible when this symptom is absent

Observer variability of absolute and relative thrombus density measurements in patients with acute ischemic stroke

Introduction: Thrombus density may be a predictor for acute ischemic stroke treatment success. However, only limited data on observer variability for thrombus density measurements exist. This study assesses the variability and bias of four common thrombus density measurement methods by expert and non-expert observers. Methods: For 132 consecutive patients with acute ischemic stroke, three experts and two trained observers determined thrombus density by placing three standardized regions of interest (ROIs) in the thrombus and corresponding contralateral arterial segment. Subsequently, absolute and relative thrombus densities were determined using either one or three ROIs. Intraclass correlation coefficient (ICC) was determined, and Bland–Altman analysis was performed to evaluate interobserver and intermethod agreement. Accuracy of the trained observer was evaluated with a reference expert observer using the same statistical analysis. Results: The highest interobserver agreement was obtained for absolute thrombus measurements using three ROIs (ICCs ranging from 0.54 to 0.91). In general, interobserver agreement was lower for relative measurements, and for using one instead of three ROIs. Interobserver agreement of trained non-experts and experts was similar. Accuracy of the trained observer measurements was comparable to the expert interobserver agreement and was better for absolute measurements and with three ROIs. The agreement between the one ROI and three ROI methods was good. Conclusion: Absolute thrombus density measurement has superior interobserver agreement compared to relative density measurement. Interobserver variation is smaller when multiple ROIs are used. Trained non-expert observers can accurately and reproducibly assess absolute thrombus densities using three ROIs

Prolonged conservative treatment or 'early' surgery in sciatica caused by a lumbar disc herniation: rationale and design of a randomized trial [ISRCT 26872154]

BACKGROUND: The design of a randomized multicenter trial is presented on the effectiveness of a prolonged conservative treatment strategy compared with surgery in patients with persisting intense sciatica (lumbosacral radicular syndrome). METHODS/DESIGN: Patients presenting themselves to their general practitioner with disabling sciatica lasting less than twelve weeks are referred to the neurology outpatient department of one of the participating hospitals. After confirmation of the diagnosis and surgical indication MRI scanning is performed. If a distinct disc herniation is discerned which in addition covers the clinically expected site the patient is eligible for randomization. Depending on the outcome of the randomization scheme the patient will either be submitted to prolonged conservative care or surgery. Surgery will be carried out according to the guidelines and between six and twelve weeks after onset of complaints. The experimental therapy consists of a prolonged conservative treatment under supervision of the general practitioner, which may be followed by surgical intervention in case of persisting or progressive disability. The main primary outcome measure is the disease specific disability of daily functioning. Other primary outcome measures are perceived recovery and intensity of legpain. Secondary outcome measures encompass severity of complaints, quality of life, medical consumption, absenteeism, costs and preference. The main research question will be answered at 12 months after randomization. The total follow-up period covers two years. DISCUSSION: Evidence is lacking concerning the optimal treatment of lumbar disc induced sciatica. This pragmatic randomized trial, focusses on the 'timing' of intervention, and will contribute to the decision of the general practictioner and neurologist, regarding referral of patients for surgery

Automated entire thrombus density measurements for robust and comprehensive thrombus characterization in patients with acute ischemic stroke

Background and Purpose: In acute ischemic stroke (AIS) management, CT-based thrombus density has been associated with treatment success. However, currently used thrombus measurements are prone to inter-observer variability and oversimplify the heterogeneous thrombus composition. Our aim was first to introduce an automated method to assess the entire thrombus density and then to compare the measured entire thrombus density with respect to current standard manual measurements. Materials and Method: In 135 AIS patients, the density distribution of the entire thrombus was determined. Density distributions were described usingmedians, interquartile ranges (IQR), kurtosis, and skewedness. Differences between themedian of entire thrombusmeasurements and commonly applied manualmeasurements using 3 regions of interest were determined using linear regression. Results: Density distributions varied considerably with medians ranging from 20.0 to 62.8 HU and IQRs ranging from 9.3 to 55.8 HU. The average median of the thrombus density distributions (43.5 ± 10.2 HU) was lower than the manual assessment (49.6 ± 8.0 HU) (p<0.05). The difference between manual measurements and median density of entire thrombus decreased with increasing density (r = 0.64; p<0.05), revealing relatively higher manual measurements for low density thrombi such that manual density measurement tend overestimates the real thrombus density. Conclusions: Automatic measurements of the full thrombus expose a wide variety of thrombi density distribution, which is not grasped with currently used manual measurement. Furthermore, d

Two-year clinical follow-up of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN): Design and statistical analysis plan of the extended follow-up study

Background: MR CLEAN was the first randomized trial to demonstrate the short-term clinical effectiveness of endovascular treatment in patients with acute ischemic stroke caused by large vessel occlusion in the anterior circulation. Several other trials confirmed that endovascular treatment improves clinical outcome at three months. However, limited data are available on long-term clinical outcome. We aimed to estimate the effect of endovascular treatment on functional outcome at two-year follow-up in patients with acute ischemic stroke. Secondly, we aimed to assess the effect of endovascular treatment on major vascular events and mortality during two years of follow-up. Methods: MR CLEAN is a multicenter clinical trial with randomized treatment allocation, open-label treatment, and blinded endpoint evaluation. Patients included were 18 years or older with acute ischemic stroke caused by a proven anterior proximal artery occlusion who could be treated within six hours after stroke onset. The intervention contrast was endovascular treatment and usual care versus no endovascular treatment and usual care. The current study extended the follow-up duration from three months to two years. The primary outcome is the score on the modified Rankin scale at two years. Secondary outcomes include all-cause mortality and the occurrence of major vascular events within two years of follow-up. Discussion: The results of our study provide information on the long-term clinical effectiveness of endovascular treatment, which may have implications for individual treatment decisions and estimates of cost-effectiveness. Trial registration:NTR1804. Registered on 7 May 2009; ISRCTN10888758. Registered on 24 July 2012 (main MR CLEAN trial); NTR5073. Registered on 26 February 2015 (extended follow-up study)

Specific treatment of problems of the spine (STOPS): design of a randomised controlled trial comparing specific physiotherapy versus advice for people with subacute low back disorders

<p>Abstract</p> <p>Background</p> <p>Low back disorders are a common and costly cause of pain and activity limitation in adults. Few treatment options have demonstrated clinically meaningful benefits apart from advice which is recommended in all international guidelines. Clinical heterogeneity of participants in clinical trials is hypothesised as reducing the likelihood of demonstrating treatment effects, and sampling of more homogenous subgroups is recommended. We propose five subgroups that allow the delivery of specific physiotherapy treatment targeting the pathoanatomical, neurophysiological and psychosocial components of low back disorders. The aim of this article is to describe the methodology of a randomised controlled trial comparing specific physiotherapy treatment to advice for people classified into five subacute low back disorder subgroups.</p> <p>Methods/Design</p> <p>A multi-centre parallel group randomised controlled trial is proposed. A minimum of 250 participants with subacute (6 weeks to 6 months) low back pain and/or referred leg pain will be classified into one of five subgroups and then randomly allocated to receive either physiotherapy advice (2 sessions over 10 weeks) or specific physiotherapy treatment (10 sessions over 10 weeks) tailored according to the subgroup of the participant. Outcomes will be assessed at 5 weeks, 10 weeks, 6 months and 12 months following randomisation. Primary outcomes will be activity limitation measured with a modified Oswestry Disability Index as well as leg and back pain intensity measured on separate 0-10 Numerical Rating Scales. Secondary outcomes will include a 7-point global rating of change scale, satisfaction with physiotherapy treatment, satisfaction with treatment results, the Sciatica Frequency and Bothersomeness Scale, quality of life (EuroQol-5D), interference with work, and psychosocial risk factors (Orebro Musculoskeletal Pain Questionnaire). Adverse events and co-interventions will also be measured. Data will be analysed according to intention to treat principles, using linear mixed models for continuous outcomes, Mann Whitney U tests for ordinal outcomes, and Chi-square, risk ratios and risk differences for dichotomous outcomes.</p> <p>Discussion</p> <p>This trial will determine the difference in outcomes between specific physiotherapy treatment tailored to each of the five subgroups versus advice which is recommended in guidelines as a suitable treatment for most people with a low back disorder.</p> <p>Trial registration</p> <p>Australia and New Zealand Clinical Trials Register (ANZCTR): <a href="http://www.anzctr.org.au/ACTRN12609000834257.aspx">ACTRN12609000834257</a>.</p