Table 1.

Summary of inclusion and exclusion criteria and PICOS literature search framework

	RSV-LRTI exposure studies	RSV immunoprophylaxis studies
Population characteristics	Human participants	Human participants
Intervention or exposure*	RSV-LRTI during a period beginning <2 years of age and fully contained within ages 0–5 years (operationalised as an exposure or mediator variable)	RSV immunoprophylaxis with established efficacy (either from the trial in question or past RCTs) in preventing or mitigating RSV-LRTI
Comparator	LRTI absent or undetected during the exposure period	RSV immunoprophylaxis not received during the exposure period
Outcome	Wheezing illness measured subsequent† to the index RSV-LRTI illness that defines inclusion in the exposure vs comparator groups	Wheezing illness subsequent to study intervention protection period
Study design	Study analysed quantitative data and was published (including online only publication ahead of print) in English language in a peer-reviewed journal before the final search date; exposure and comparator groups sampled from the same population; method of ascertaining exposure and outcomes were the same for exposure and comparator groups	As for exposure studies

PICOS=population, intervention or exposure, comparator, outcome, study design. RSV=respiratory syncytial virus. LRTI=lower respiratory tract infection. RCT=randomised controlled trial.

^*Clinical trials might estimate the effect of RSV-LRTI on asthma or wheezing outcomes indirectly by reporting the effect of immunoprophylaxis on asthma or wheezing outcomes and report the direct association between RSV-LRTI and asthma or wheezing outcomes.

^†Defined as occurring >30 days after the index RSV-LRTI.