Core Outcomes and Common Data Elements in Chronic Subdural Hematoma: A Systematic Review of the Literature Focusing on Reported Outcomes

Abstract

The plethora of studies in chronic subdural hematoma (CSDH) has not resulted in the development of an evidence-based treatment strategy, largely due to heterogeneous outcome measures that preclude cross-study comparisons and guideline development. This study aimed to identify and quantify the heterogeneity of outcome measures reported in the CSDH literature and to build a case for the development of a consensus-based core outcome set. This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was registered with the PROSPERO international prospective register of systematic reviews (CRD42014007266). All full-text English language studies with >10 patients (prospective) or >100 patients (retrospective) published after 1990 examining clinical outcomes in CSDH were eligible for inclusion. One hundred two eligible studies were found. There were 14 (13.7%) randomized controlled trials, one single arm trial (1.0%), 25 (24.5%) cohort comparison studies, and 62 (60.8%) prospective or retrospective cohort studies. Outcome domains reported by the studies included mortality (63.8% of included studies), recurrence (94.1%), complications (48.0%), functional outcomes (40.2%), and radiological (38.2%) outcomes. There was significant heterogeneity in the definitions of the outcome measures, as evidenced by the seven different definitions of the term “recurrence,” with no definition given in 19 studies. The time-points of assessment for all the outcome domains varied greatly from inpatient/hospital discharge to 18 months. This study establishes and quantifies the heterogeneity of outcome measure reporting in CSDH and builds the case for the development of a robust consensus-based core outcome set for future studies to adhere to as part of the Core Outcomes and Common Data Elements in CSDH (CODE-CSDH) project.

Core Outcomes and Common Data Elements in Chronic Subdural Hematoma: A Systematic Review of the Literature Focusing on Baseline and Peri-Operative Care Data Elements

“…It successfully establishes the basis for the development of a consensus-based set of common data elements, including standardised terminology for operative technique, as part of the Core Outcomes and common Data Elements in Chronic Subdural Haematoma (CODE-CSDH) project. 6…”

“…Further details about the studies are available in our previous study. 6 A risk of bias tool was not applied to the included studies as the inherent nature of the present study was to assess risk of bias based on study design and reporting. The complete list of included studies is provided in our previous study.…”

“…10 In addition to the development of a set of common data elements, the Core Outcomes and common Data Elements in Chronic Subdural Haematoma (CODE-CSDH) project (figure 5) also aims to develop a set of core outcomes for CSDH. 6 By standardising a minimum set of data elements and outcome measures to be collected by all future CSDH studies, future reports on aspects of CSDH treatment can serve as a more robust basis for our understanding of this common condition and will allow meaningful cross-study comparison of established and novel therapeutic interventions.…”

“…One of the main barriers is the collection of heterogeneous data points, be that pre-operative patient data, details on operative intervention or clinical outcomes. 1,3,5,6 Our recent systematic review identified the heterogeneity in outcome measures. 6 Harmonising these outcome measures, which can be achieved through the development of a core outcome set, 7,8 is meaningless without standardising the collection of data in the pre-operative, intra-operative and post-operative phases of care.…”

“…1,3,5,6 Our recent systematic review identified the heterogeneity in outcome measures. 6 Harmonising these outcome measures, which can be achieved through the development of a core outcome set, 7,8 is meaningless without standardising the collection of data in the pre-operative, intra-operative and post-operative phases of care. This facilitates standardised comparisons across studies, allowing for adjustment of differences in independent variables in the study populations.…”