Mark H Ebell1, Mary E Walsh2, Tom Fahey2, Maggie Kearney3, Christian Marchello3. 1. Department of Epidemiology and Biostatistics, College of Public Health , University of Georgia, Athens, GA, USA. ebell@uga.edu. 2. HRB Centre for Primary Care Research, Department of General Practice, Royal College of Surgeons in Ireland, Dublin, Republic of Ireland. 3. Department of Epidemiology and Biostatistics, College of Public Health , University of Georgia, Athens, GA, USA.
Abstract
BACKGROUND: The CRB-65 score is recommended as a decision support tool to help identify patients with community-acquired pneumonia (CAP) who can safely be treated as outpatients. OBJECTIVE: To perform an updated meta-analysis of the accuracy, discrimination, and calibration of the CRB-65 score using a novel approach to calculation of stratum-specific likelihood ratios. DESIGN: Meta-analysis of accuracy, discrimination, and calibration. METHODS: We searched PubMed, Google, previous systematic reviews, and reference lists of included studies. Data was abstracted and quality assessed in parallel by two investigators. The quality assessment used an adaptation of the TRIPOD and PROBAST criteria. Measures of discrimination, calibration, and stratum-specific likelihood ratios are reported. KEY RESULTS: Twenty-nine studies met our inclusion criteria and provided usable data. Most studies were set in Europe, none in North America, and 12 were judged to be at low risk of bias. The pooled estimate of area under the receiver operating characteristic curve was 0.74 (95% CI 0.71-0.77) for all studies. Calibration was good although there was significant heterogeneity; the pooled estimate of the ratio of observed to expected mortality for all studies was 1.04 (95% CI 0.91-1.19). The corresponding values for studies at low risk of bias where patients could be treated as outpatients or inpatients were 0.76 (0.70-0.81) and 0.88 (0.69-1.13). Summary estimates of stratum-specific likelihood ratios for all studies were 0.19 for the low-risk group, 1.1 for the moderate-risk group, and 4.5 for the high-risk group, and 0.13, 1.3, and 5.6 for studies at low risk of bias where patients could be treated as outpatients or inpatients. CONCLUSIONS: The CRB-65 is useful for identifying low-risk patients for outpatient therapy. Given a 4% overall mortality risk, patients classified as low risk by the CRB-65 had an outpatient mortality risk of no more than 0.5%.
BACKGROUND: The CRB-65 score is recommended as a decision support tool to help identify patients with community-acquired pneumonia (CAP) who can safely be treated as outpatients. OBJECTIVE: To perform an updated meta-analysis of the accuracy, discrimination, and calibration of the CRB-65 score using a novel approach to calculation of stratum-specific likelihood ratios. DESIGN: Meta-analysis of accuracy, discrimination, and calibration. METHODS: We searched PubMed, Google, previous systematic reviews, and reference lists of included studies. Data was abstracted and quality assessed in parallel by two investigators. The quality assessment used an adaptation of the TRIPOD and PROBAST criteria. Measures of discrimination, calibration, and stratum-specific likelihood ratios are reported. KEY RESULTS: Twenty-nine studies met our inclusion criteria and provided usable data. Most studies were set in Europe, none in North America, and 12 were judged to be at low risk of bias. The pooled estimate of area under the receiver operating characteristic curve was 0.74 (95% CI 0.71-0.77) for all studies. Calibration was good although there was significant heterogeneity; the pooled estimate of the ratio of observed to expected mortality for all studies was 1.04 (95% CI 0.91-1.19). The corresponding values for studies at low risk of bias where patients could be treated as outpatients or inpatients were 0.76 (0.70-0.81) and 0.88 (0.69-1.13). Summary estimates of stratum-specific likelihood ratios for all studies were 0.19 for the low-risk group, 1.1 for the moderate-risk group, and 4.5 for the high-risk group, and 0.13, 1.3, and 5.6 for studies at low risk of bias where patients could be treated as outpatients or inpatients. CONCLUSIONS: The CRB-65 is useful for identifying low-risk patients for outpatient therapy. Given a 4% overall mortality risk, patients classified as low risk by the CRB-65 had an outpatientmortality risk of no more than 0.5%.
Authors: W S Lim; M M van der Eerden; R Laing; W G Boersma; N Karalus; G I Town; S A Lewis; J T Macfarlane Journal: Thorax Date: 2003-05 Impact factor: 9.139
Authors: Lionel A Mandell; Richard G Wunderink; Antonio Anzueto; John G Bartlett; G Douglas Campbell; Nathan C Dean; Scott F Dowell; Thomas M File; Daniel M Musher; Michael S Niederman; Antonio Torres; Cynthia G Whitney Journal: Clin Infect Dis Date: 2007-03-01 Impact factor: 9.079
Authors: A Capelastegui; P P España; J M Quintana; I Areitio; I Gorordo; M Egurrola; A Bilbao Journal: Eur Respir J Date: 2006-01 Impact factor: 16.671
Authors: Shin Yan Man; Nelson Lee; Margaret Ip; Gregory E Antonio; Shirley S L Chau; Paulina Mak; Colin A Graham; Mingdong Zhang; Grace Lui; Paul K S Chan; Anil T Ahuja; David S Hui; Joseph J Y Sung; Timothy H Rainer Journal: Thorax Date: 2006-11-22 Impact factor: 9.139
Authors: Kirsty L Buising; Karin A Thursky; James F Black; Lachlan MacGregor; Alan C Street; Marcus P Kennedy; Graham V Brown Journal: Emerg Med Australas Date: 2007-10 Impact factor: 2.151