Table 1.
Characteristics of included studies
| Author | Year | Study design | Sample size | Inclusion criteria | Exclusion criteria | Time of outcome assessment | Primary outcome | Key secondary outcomes | Comments |
|---|---|---|---|---|---|---|---|---|---|
| OHCA score | |||||||||
| Adrie et al. (development cohort) | 2006 | PCS single-centre | 130 | OHCA | Age < 18 years | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Adrie et al. (validation cohort) | 2006 | PCS multicentre | 210 | OHCA | Age < 18 years | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Hunziker et al | 2011 | RCS bi-centre | 128 | OHCA | Age < 18 years; traumatic aetiology | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Skrifvars et al | 2012 | PCS single-centre | 122 | OHCA and IHCA | ROSC without chest compressions | Hospital discharge | Mortality | ICU mortality, mortality at 1 month | |
| Bisbal et al | 2014 | RCS single-centre | 124 | OHCA and IHCA | Age < 18 years; death within 1 h after ROSC | Hospital discharge | Mortality | Poor neurological outcome (CPC > 2) at ICU discharge, 3, 6 and 12 months | Primary aim: Validation of SAPS III score |
| Sauneuf et al | 2016 | PCS single-centre | 204 | OHCA | Age < 18 years; pregnancy; immunosuppression | Hospital discharge | Poor neurological outcome (CPC > 2) | None | Primary aim: Development of MyeloScore |
| Choi et al | 2018 | RCS single-centre | 173 | OHCA treated with TTM | Traumatic aetiology | 1 month | Poor neurological outcome (CPC > 2) | None | |
| Isenschmid et al | 2019 | PCS single-centre | 349 | OHCA and IHCA | Age < 16 years; monitored IHCA | Hospital discharge | Mortality | Poor neurological outcome (CPC > 2) at hospital discharge, mortality at 1 month | |
| Chelly et al | 2020 | RCS multicentre | 381 | IHCA | Age < 18 years; GCS > 8; monitored IHCA | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Kim et al | 2020 | RCS single-centre | 311 | OHCA treated with TTM | None | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Pareek et al. (KOCAR cohort) | 2020 | PCS multicentre | 373 | OHCA | Age < 18 years; non-cardiac aetiology; intracranial bleeding; CPC > 2 prior to admission; life-expectancy < 6 months; GCS 15 at admission | 6 months | Poor neurological outcome (CPC > 2) | None | Primary aim: Development of MIRACLE2 score |
| Pareek et al. (Ljubljana cohort) | 2020 | PCS single-centre | 325 | OHCA | Age < 18 years; non-cardiac aetiology; intracranial bleeding; CPC > 2 prior to admission; life-expectancy < 6 months; GCS 15 at admission | Hospital discharge | Poor neurological outcome (CPC > 2) | None | Primary aim: Validation of MIRACLE2 score |
| Pareek et al. (RFH cohort) | 2020 | PCS single-centre | 148 | OHCA | Age < 18 years; non-cardiac aetiology; intracranial bleeding; CPC > 2 prior to admission; life-expectancy < 6 months; GCS 15 at admission | 6 months | Poor neurological outcome (CPC > 2) | None | Primary aim: Validation of MIRACLE2 score |
| Bae et al | 2021 | RCS single-centre | 297 | OHCA | Age < 18 years; traumatic aetiology; stroke; unwitnessed OHCA; CPC 2 prior to admission | Hospital discharge | Poor neurological outcome (CPC > 2) | None | Primary aim: Development and validation of PROLOGUE score; no WLST allowed unless patients were pronounced brain dead |
| Pham et al | 2021 | PCS single-centre | 386 | OHCA due to ACS treated with PCI | None | Hospital discharge | Mortality | None | |
| Shibahashi et al | 2021 | PCS multicentre | 2428 | OHCA | Age < 18 years; extrinsic aetiology (trauma, burn, hypothermia, drowning, asphyxiation, intoxication) | 1 month | Poor neurological outcome (CPC > 2) | None | Primary aim: Validation of sOHCA and sCAHP scores |
| Song et al | 2021 | RCS single-centre | 106 | OHCA treated with TTM | Age < 18 years; traumatic aetiology; ineligibility for TTM; TTM induced > 6 h after ROSC; failure to maintain target temperature | 3 months | Poor neurological outcome (CPC > 2) | None | |
| Tsuchida et al | 2021 | RCS single-centre | 189 | OHCA | Age < 18 years; transfers from other hospitals | 1 month | Poor neurological outcome (CPC > 2) | None | |
| CAHP score | |||||||||
| Maupain et al. (development cohort) | 2016 | PCS multicentre | 819 | OHCA | Extrinsic aetiology (trauma, hypothermia, drowning, asphyxiation, intoxication) | ICU discharge | Poor neurological outcome (CPC > 2) | None | |
| Maupain et al. (internal validation cohort) | 2016 | PCS multicentre | 1129 | OHCA | Extrinsic aetiology (trauma, hypothermia, drowning, asphyxiation, intoxication) | ICU discharge | Poor neurological outcome (CPC > 2) | None | |
| Maupain et al. (external validation cohort) | 2016 | RCS single-centre | 367 | OHCA | Extrinsic aetiology (trauma, hypothermia, drowning, asphyxiation, intoxication) | ICU discharge | Poor neurological outcome (CPC > 2) | None | |
| Sauneuf et al | 2016 | PCS single-centre | 204 | OHCA | Age < 18 years; pregnancy; immunosuppression | Hospital discharge | Poor neurological outcome (CPC > 2) | None | Primary aim: Development of the MyeloScore |
| Isenschmid et al | 2019 | PCS single-centre | 349 | OHCA and IHCA | Age < 16 years; monitored IHCA | Hospital discharge | Mortality | Poor neurological outcome (CPC > 2) at hospital discharge, mortality at 1 month | |
| Chelly et al | 2020 | RCS multicentre | 381 | IHCA | Age < 18 years; GCS > 8; monitored IHCA | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Kim et al | 2020 | RCS single-centre | 311 | OHCA treated with TTM | None | Hospital discharge | Poor neurological outcome (CPC > 2) | None | |
| Pareek et al. (KOCAR cohort) | 2020 | PCS multicentre | 373 | OHCA | Age < 18 years; non-cardiac aetiology; intracranial bleeding; CPC > 2 prior to admission; life-expectancy < 6 months; GCS 15 at admission | 6 months | Poor neurological outcome (CPC > 2) | None | Primary aim: Development of MIRACLE2 score |
| Pareek et al. (Ljubljana cohort) | 2020 | PCS single-centre | 325 | OHCA | Age < 18 years; non-cardiac aetiology; intracranial bleeding; CPC > 2 prior to admission; life-expectancy < 6 months; GCS 15 at admission | Hospital discharge | Poor neurological outcome (CPC > 2) | None | Primary aim: Validation of MIRACLE2 score |
| Pareek et al. (RFH cohort) | 2020 | PCS single-centre | 148 | OHCA | Age < 18 years; non-cardiac aetiology; intracranial bleeding; CPC > 2 prior to admission; life-expectancy < 6 months; GCS 15 at admission | 6 months | Poor neurological outcome (CPC > 2) | None | Primary aim: Validation of MIRACLE2 score |
| Sauneuf et al | 2020 | RCS multicentre | 176 | OHCA in patients > 75 years | Non-French speaking patients; traumatic aetiology; conscious patients | Hospital discharge | Poor neurological outcome (CPC > 2) | Poor neurological outcome (CPC > 2) at 6 and 12 months | |
| Bae et al | 2021 | RCS single-centre | 297 | OHCA | Age < 18 years; traumatic aetiology; stroke; unwitnessed OHCA; CPC > 2 prior to admission | Hospital discharge | Poor neurological outcome (CPC > 2) | None | Primary aim: Development and validation of PROLOGUE score; no WLST allowed unless patients were pronounced brain dead |
| Pham et al | 2021 | PCS single-centre | 386 | OHCA due to ACS treated with PCI | None | Hospital discharge | Mortality | None | |
| Shibahashi et al | 2021 | PCS multicentre | 2428 | OHCA | Age < 18 years; extrinsic aetiology (trauma, burn, hypothermia, drowning, asphyxiation, intoxication) | 1 month | Poor neurological outcome (CPC > 2) | None | Primary aim: Validation of sOHCA and sCAHP scores |
| Song et al | 2021 | RCS single-centre | 106 | OHCA treated with TTM | Age < 18 years; traumatic aetiology; ineligibility for TTM; TTM induced > 6 h after ROSC; failure to maintain target temperature | 3 months | Poor neurological outcome (CPC > 2) | None | |
| Tsuchida et al | 2021 | RCS single-centre | 189 | OHCA | Age < 18 years; transfers from other hospitals | 1 month | Poor neurological outcome (CPC > 2) | None | |
| Vedamurthy et al | 2021 | RCS single-centre | 158 | OHCA | Extrinsic aetiology (trauma, asphyxiation, pulmonary embolism, exacerbated chronic lung disease) | Hospital discharge | Mortality | Poor neurological outcome (CPC > 2) at hospital discharge | |
| GO-FAR score | |||||||||
| Ebell et al. (development and internal validation cohort) | 2013 | PCS multicentre | 51,240 | IHCA | None | Hospital discharge | Good neurological outcome (CPC = 1) | None | Cohort randomly divided into development, training and test data sets |
| Ohlsson et al | 2016 | RCS single-centre | 287 | IHCA | Age < 18 years | Hospital discharge | Good neurological outcome (CPC = 1) | Mortality | |
| Piscator et al | 2018 | RCS multicentre | 717 | IHCA | Age < 18 years | Hospital discharge | Good neurological outcome (CPC = 1) | None | |
| Rubins et al | 2019 | RCS single-centre | 403 | IHCA | Age < 18 years | Hospital discharge | Good neurological outcome (CPC = 1) | Mortality | |
| Thai et al | 2019 | PCS multicentre | 62,131 | IHCA | Age < 18 years | Hospital discharge | Good neurological outcome (CPC = 1) | None | |
| Cho et al | 2020 | RCS single-centre | 1011 | IHCA | Age < 18 years; major trauma | Hospital discharge | Good neurological outcome (CPC < 3) | Good neurological outcome (CPC = 1) | |
| Aldabagh et al | 2021 | RCS single-centre | 884 | IHCA | Age < 18 years; transfers from other hospitals; patients who changed their status to do-not-resuscitate after survived IHCA | Hospital discharge | Mortality | None | Included 60.2% COVID-19 patients |
ACS Acute coronary syndrome; CAHP Cardiac Arrest Hospital Prognosis; COVID-19 Coronavirus disease 2019; CPC Cerebral Performance Category; GCS Glasgow Coma Scale; GO-FAR Good Outcome Following Attempted Resuscitation; ICU Intensive care unit; IHCA In-hospital cardiac arrest; KOCAR King’s Out-of-Hospital Cardiac Arrest Registry; OHCA Out-of-hospital cardiac arrest; PCI Percutaneous coronary intervention; PCS Prospective cohort study; RCS Retrospective cohort study; RFH Royal Free Hospital London; ROSC Return of spontaneous circulation; TTM Targeted temperature management; WLST Withdrawal of life-sustaining therapy