Mortality during admission was derived from the GRO death record linked to the SMR.
Information on the reason for hospital admission was derived from the ED records, and the final diagnosis was retrieved from the clinical records after discharge.
The time to the patients' first mobilisation out of bed both from the time of stroke onset and from the time of hospital admission was derived from the patients' medical records.
Rehabilitation access was derived from Admission/Discharge Rehabilitation Report (ADRR), for hospital rehabilitation, and from Residential Rehabilitation Information System (RRIS).
Length of stay in the general ward and ICU, as well as the risk of ICU admission were derived from the recent Spanish CIVIC study [46].
Scores were considered if they were designed for use at the time of ER assessment and/or admission, were derived or validated in a cohort of patients with influenza, pneumonia or sepsis, and were intended to predict relevant outcomes (i.e. death, mechanical ventilation, ICU admission).
The parts of our questionnaire containing four dimensions on "tolerance of risk" and "attitudes to hospital admission" were derived from a questionnaire previously published in an article by Ingram et al. in 2009 [ 12].
Similarly, as it is an issue in all meta-analyses of observational studies, extracted predictors of NH admission were derived from studies that included models with varying numbers of adjusting covariates; variations in adjustment across predictive models pose challenges to standardization when pooling estimates in meta-analyses.
Of the 451 included patients, in a small proportion of patients (n = 23) pre-admission HRQOL was derived from the patients themselves, whereas all other SF-36 scores were obtained from proxies.
Admission diagnosis was derived from APACHE III diagnostic categories, with new groupings created by manual review by one of the authors (NL) for pneumonia, trauma, and sepsis [see Additional file 1, Table S2].
