A chest radiograph scoring system in patients with severe acute respiratory infection: a validation study

Abstract

BackgroundThe term severe acute respiratory infection (SARI) encompasses a heterogeneous group of respiratory illnesses. Grading the severity of SARI is currently reliant on indirect disease severity measures such as respiratory and heart rate, and the need for oxygen or intensive care. With the lungs being the primary organ system involved in SARI, chest radiographs (CXRs) are potentially useful for describing disease severity. Our objective was to develop and validate a SARI CXR severity scoring system.MethodsWe completed validation within an active SARI surveillance project, with SARI defined using the World Health Organization case definition of an acute respiratory infection with a history of fever, or measured fever of ≥ 38 °C; and cough; and with onset within the last 10 days; and requiring hospital admission. We randomly selected 250 SARI cases. Admission CXR findings were categorized as: 1 = normal; 2 = patchy atelectasis and/or hyperinflation and/or bronchial wall thickening; 3 = focal consolidation; 4 = multifocal consolidation; and 5 = diffuse alveolar changes.Initially, four radiologists scored CXRs independently. Subsequently, a pediatrician, physician, two residents, two medical students, and a research nurse independently scored CXR reports. Inter-observer reliability was determined using a weighted Kappa (κ) for comparisons between radiologists; radiologists and clinicians; and clinicians. Agreement was defined as moderate (κ > 0.4–0.6), good (κ > 0.6–0.8) and very good (κ > 0.8–1.0).ResultsAgreement between the two pediatric radiologists was very good (κ = 0.83, 95 % CI 0.65–1.00) and between the two adult radiologists was good (κ = 0.75, 95 % CI 0.57–0. 93).Agreement of the clinicians with the radiologists was moderate-to-good (pediatrician:κ = 0.65; pediatric resident:κ = 0.69; physician:κ = 0.68; resident:κ = 0.67; research nurse:κ = 0.49, medical students: κ = 0.53 and κ = 0.56).Agreement between clinicians was good-to-very good (pediatrician vs. physician:κ = 0.85; vs. pediatric resident:κ = 0.81; vs. medicine resident:κ = 0.76; vs. research nurse:κ = 0.75; vs. medical students:κ = 0.63 and 0.66).Following review of discrepant CXR report scores by clinician pairs, κ values for radiologist-clinician agreement ranged from 0.59 to 0.70 and for clinician-clinician agreement from 0.97 to 0.99.ConclusionsThis five-point CXR scoring tool, suitable for use in poorly- and well-resourced settings and by clinicians of varying experience levels, reliably describes SARI severity. The resulting numerical data enables epidemiological comparisons of SARI severity between different countries and settings.

Progression of the Radiologic Severity Index predicts mortality in patients with parainfluenza virus-associated lower respiratory infections

“…For example, El Solh et al found that when determining whether chest radiographs had consolidation, interstitial infiltrates, or a mixed pattern, the kappa statistic between two radiologists was 0.6. [42] Taylor et al found a kappa statistic of 0.75-0.83 between two radiologists when using a 5-point scale for pneumonia severity [16]. In comparison, we observed an ICC of 0.99 between two expert radiologists scoring RSI on a 72-point scale, which is excellent and compares favorably to the reliability reported by other investigators.…”

“…Systematic quantification of radiological severity could allow for a valid and reliable score that can serve as a biomarker of mortality. While thoracic computed tomography (CT) and chest X-ray (CXR) are important clinical tools for evaluating pneumonia [13], few studies have sought to quantify pneumonia severity radiologically [14][15][16]. Precise, quantitative imagebased assessments of pneumonia may add prognostic value to existing clinical risk assessment tools [17], and changes in radiologic severity may predict adverse outcomes after pneumonia [6].…”

COVID-19 outbreak in Italy: experimental chest X-ray scoring system for quantifying and monitoring disease progression

“…At the present time, different CT scoring systems and only one CXR scoring system were applied to quantify the pulmonary involvement in COVID-19 [6,7,11]. This CXR scoring system is a simple five-point grading tool that was proposed in 2015, and it was designed for non-radiologist clinicians [15]. The goal of this scoring system was to facilitate the clinical grading of CXR reports into five different severity categories in hospitalized patients with acute respiratory infection.…”

COVID-19 outbreak in Italy: Experimental chest x-ray scoring system for quantifying and monitoring disease progression

“…At the present time, two different CT scoring systems and one CXR scoring system were used to quantify the pulmonary involvement in COVID-19 infection [6,7,11]. This CXR scoring system is a simple five-point grading tool that was proposed in 2015, and it was designed for non-radiologist clinicians [15]. The goal of this scoring system was to facilitate the clinical grading of CXR reports into five different severity categories in hospitalized patients with acute respiratory infection.…”