Initial assessment and management of adults with suspected acute respiratory infection: a rapid evidence synthesis of reviews and cost-effectiveness studies.

Background: This work was undertaken to inform a National Institute for Health and Care Excellence guideline on the initial assessment of adults with suspected acute respiratory infection.

Objective: To undertake a rapid evidence synthesis of systematic reviews and cost-effectiveness studies of signs, symptoms and early warning scores for the initial assessment of adults with suspected acute respiratory infection.

Methods: MEDLINE, EMBASE and Cochrane Database of Systematic Reviews were searched for systematic reviews and MEDLINE, EMBASE, EconLit and National Health Service Economic Evaluation Database were searched for cost-effectiveness studies in May 2023. References of relevant studies were checked. Clinical outcomes of interest included escalation of care, antibiotic/antiviral use, time to resolution of symptoms, mortality and health-related quality of life. Risk of bias was assessed using the Risk of Bias in Systematic Reviews tool or the National Institute for Health and Care Excellence economic evaluations checklist. Results were summarised using narrative synthesis.

Results: Nine systematic reviews and one cost-effectiveness study met eligibility criteria. Seven reviews assessed several early warning scores for patients with community- acquired pneumonia, one assessed early warning scores for nursing home-acquired pneumonia and one assessed individual signs/symptoms and the Centor score for patients with sore throat symptoms; all in face-to-face settings. Two good-quality reviews concluded that further research is needed to validate the CRB-65 in primary care/community settings. One also concluded that further research is needed on the Pneumonia Severity Index in community settings; however, the Pneumonia Severity Index requires data from tests not routinely conducted in community settings. One good-quality review concluded that National Early Warning Score appears to be useful in an emergency department/acute medical setting. One review (unclear quality) concluded that the Pneumonia Severity Index and CURB-65 appear useful in an emergency department setting. Two poor-quality reviews concluded that early warning scores can support clinical judgement and one poor-quality review found numerous problems with using early warning scores in a nursing home setting. A good-quality review concluded that individual signs and symptoms have a modest ability to diagnose streptococcal pharyngitis, and that the Centor score can enhance appropriate prescribing of antibiotics. The cost-effectiveness study assessed clinical scores and rapid antigen detection tests for sore throat, compared to delayed antibiotic prescribing. The study concluded that the clinical score is a cost-effective approach when compared to delayed prescribing and rapid antigen testing.

Conclusions: Several early warning scores have been evaluated in adults with suspected acute respiratory infection, mainly the CRB-65, CURB-65 and Pneumonia Severity Index in patients with community-acquired pneumonia. The evidence was insufficient to determine what triage strategies avoid serious illness. Some early warning scores (CURB-65, Pneumonia Severity Index and National Early Warning Score) appear to be useful in an emergency department/acute medical setting; however, further research is required to validate the CRB-65 and Pneumonia Severity Index in primary care/community settings. The economic evidence indicated that clinical scores may be a cost-effective approach to triage patients compared with delayed prescribing.

Future work and limitations: Only systematic reviews were eligible for inclusion in the synthesis of clinical evidence. There was a great deal of overlap in the primary studies included in the reviews, many of which had significant limitations. No studies were undertaken in remote settings (e.g. NHS 111). Only one cost-effectiveness study was identified, with limited applicability to the review question.

Funding: This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number NIHR159945.