Background: Following the famous “Time is Brain” mantra, time measures are a natural focus of reporting in studies of stroke interventions. Such measures are often highly skewed, therefore the focus on means and standard deviations can be misleading. Moreover, there is inconsistency in how these measures are reported and compared and a lack of clarity in how compatible the reporting methods are with the chosen statistical analysis methods.
Aim: To investigate the reporting and statistical comparison of process-of-care time measures in published hyperacute stroke trials and systematic reviews of trials.
Methods: A scoping review of studies that reported and/or compared time measures between key events of interest in the delivery of hyperacute stroke care was undertaken (Protocol DOI: 10.11124/JBIES-23-00136). Out of 2,321 studies identified through a database search, 328 full-text articles assessed for eligibility and 146 studies included in the scoping review (121 individual studies, 25 systematic reviews).
Results: 50 (34%) reported a process-of-care time measure using the mean/SD. Under the assumption of the normal distribution, physically impossible (negative) values of time would have been observed in 40 (79%) of those studies. Out of studies statistically comparing time measures (62), 11 (18%) used analysis methods inconsistent with the chosen reporting methods.
Conclusion: We recommend that stroke researchers: (i) exercise awareness of pitfalls in inappropriate reporting and analysis of time measures; (ii) summarise time measures using the median/IQR and use consistent analysis methods; (iii) utilise available methods for median-based meta-analysis to ensure that such studies are not excluded from systematic reviews.