Imaging

Ultrasound (US) | 33 studies | 4,901 individuals

31 studies out of 33 (94%) enrolled patients presenting with signs and symptoms suggestive of community-acquired pneumonia. All the studies were performed at emergency department (ED). The comparator for Ultrasound (US) was chest X-ray in 18 studies (54%), computed tomography (CT) scan in 8 studies (24%), expert consensus in two (6%) and diagnosis at discharge in three (9%). The use of Ultrasound for the detection of bacterial community-acquired pneumonia demonstrated both high sensitivity and specificity [(92% (CI, 88% to 95%) and 90% (CI, 81% to 95%), respectively]. The diagnostic accuracy for Ultrasound examinations did not change by operator experience (Ultrasound performed by high skilled personnel: sensitivity 92% (CI, 85% to 96%), specificity 89% (CI, 75% to 96%) compared to physicians attending a Ultrasound short course: sensitivity 89% (CI, 82% to 94%), specificity 88% (CI, 69% to 96%). Ultrasound subgroup analysis by population showed a slightly better performance in adults [sensitivity: 94% (CI, 87% to 97%); specificity: 90% (CI, 79% to 95%)] compared to children [sensitivity: 89% (CI, 85% to 93%); specificity: 91% (CI, 80% to 96%)].

X-ray | 13 studies | 1,567 individuals

The comparator for chest X-ray was CT scan in 5 studies (38%), expert consensus or composite analysis in 6 studies (46%) and diagnosis at discharge in the remaining 2 (15%).

Chest X-ray showed a sub-optimal diagnostic performance [sensitivity: 75% (CI, 54% to 88%); specificity: 75% (CI, 42% to 92%), respectively]. The majority of studies (86%) were performed in adults (78%), Emergency department (92%), not allowing any subgroup analysis.

Meta-analysis results visualisation