Chest radiograph in acute respiratory infections

Chest radiography is widely used during the management of acute lower respiratory infections, but the benefits are unknown.

To assess the effects of chest radiography on clinical outcome in acute lower respiratory infections.

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 1), MEDLINE (1950 to January 2007) and EMBASE (January 1976 to February 2007).

Randomised or quasi-randomised trials of chest radiography in acute respiratory infections.

Both review authors independently applied the inclusion criteria, extracted data and assessed trial quality.

We identified two trials. One, of 522 outpatient children (and performed by the review authors), found that 46% of both radiography and control participants had recovered by seven days (relative risk (RR) 1.01, 95% confidence interval (CI) 0.79 to 1.31). Thirty-three per cent of radiography participants and 32% of control participants made a subsequent hospital visit within four weeks (RR 1.02, 95% CI 0.79 to 1.30) and 3% of both radiography and control participants were subsequently admitted to hospital within four weeks (RR 1.02, 95% CI 0.41 to 2.52). The other trial involving 1502 adults attending an emergency department found no significant difference in length of illness, the single outcome prespecified for this review (mean of 16.9 days in radiograph group versus 17.0 days in control group, P > 0.05).

There is no evidence that chest radiography improves outcome in outpatients with acute lower respiratory infection. The findings do not exclude a potential effect of radiography, but the potential benefit needs to be balanced against the hazards and expense of chest radiography. The findings apply to outpatients only.