Objective:

Demonstrate the degree to which the cardiac arrest (CA) neuroprognostic literature accounts for factors related to self-fulfilling prophecy bias (SFPB).

Background:

SFPB occurs when a perceived prognosis guides treatment decisions, thereby modulating outcomes and potentially inflating prognostic tool performance. We hypothesize that factors influencing how strongly studies are impacted by SFPB are underreported in CA neuroprognostic studies.

Design/Methods:

We searched MEDLINE, Embase, and Cochrane databases. Two independent reviewers screened and extracted data using Distiller SR® from observational studies and systematic reviews/meta-analyses (from inception-12/31/2022) evaluating the performance of guideline-recommended neuroprognostic tools in survivors of CA with Glasgow Coma Scale<8 or motor subscore<6 aged>17 years. Data were synthesized descriptively; heterogeneity of studies precluded meta-analysis.

Results:

Of 6161 articles, 221 were included. SFPB was reported in 49% (109/221) of studies with 19% (43/221) also reporting strategies to mitigate this bias. Mortality was reported in 63% (139/221) of studies, of which 44% (61/139) reported timing and 31% (43/139) reported mode of death. Furthermore, withdrawal of life-sustaining therapy (WLST)  practices—study-specific, institutional, or cultural—were reported in 46% (64/139) of studies, with 11% (7/64) reporting that cultural or protocol restrictions precluded WLST. The remaining 89% (57/64) of studies mentioned WLST, though WLST rates were provided in only 47% (27/57) with only one study excluding the tool investigated from neuroprognostic impressions informing WLST decisions. Additionally, 56% (15/27) of studies reported perceived poor neurologic prognosis as the most common indication, and in 48% (13/27) WLST occurred within 1 week of CA. Blinding was reported in 55% (122/221) of studies, including blinding of data analysts (35%; 43/122), investigators (45%; 55/122), outcome assessors (25%; 30/122), and treatment team (20%; 25/122).

Conclusions:

Factors contributing to SFPB are drastically underreported and undermine the reliability of studies informing neuroprognostication tools and guidelines in CA survivors, highlighting an opportunity for increasing transparency and rigor in future studies.