Our findings are consistent with a process of forward mortality displacement (or "harvesting"), with initial increases in mortality (mostly in already frail individuals) that are followed by deficits in expected number of deaths sometime after the initial excess.
A logistic regression model was constructed to identify independent factors associated with 30-day mortality using a forward stepwise approach.
To study the association between appropriateness, timing, and combination of antimicrobial/antibiotic therapy and hospital mortality (dependent variable), forward step-wise logistic regression analyses were performed.
It recorded where actions were necessary to address any problems; whether an adverse incident report was needed; and who was going to take any actions forward (Mortality review form: Appendix 1, web only).
Alternative explanations for the high CVD mortality were put forward by the public, e.g. pollutants from the mining industry (12), however, a general understanding of the associations between risk factors and CVD gradually increased (13).
From over 50 potential predictor variables a new risk score for one-year mortality was developed using forward stepwise Cox regression, and examined for goodness-of-fit, discriminatory power, and external validation.
As we move forward from evaluating mortality alone to include morbidity, data harmonization will become an increasing challenge.
6 This phenomenon is commonly termed harvesting, mortality displacement or deaths brought forward, and some evidence exists to support it, particularly with respect to heat-related deaths.
Similar considerations may be put forward for the mortality analysis carried out in another study on a dataset partially overlapped to the McLean series [ 21].
Multiple logistic regression modelling was performed, using the stepwise forward method, with mortality as the dependent variable and age, sex, nutritional markers and ICU variables (reason for ICU admission, SAPS II, ICU LOS) as independent variables.
