Table 1.

Recommendations for reporting and analyzing nonmortal endpoints in critical care trials, using intensive care unit (ICU) length of stay (LOS) as an example.

Domain	Problem identified in review	Recommendations
Measurement	Trials reporting start and end times for LOS varied in their definitions, and many do not report definitions.	Clearly indicate the LOS start and end times. Give special consideration to using the start of an intervention and the time when patients are deemed clinically ready for discharge for these times.
	Trials predominantly report LOS in "days." Calendar days and 24-hour periods are different, and can further vary based on the above-mentioned issue of start and end times. This potentially adds measurement error.	Measure LOS in hours or 24-hour periods with decimal places.
Analysis	Many trials simply state that nonparametric or parametric statistical models were used without any further detail. It is unclear in some trials which model was used to generate the reported p-value.	Clearly report the statistical method used to compare LOS between study arms.
	The treatment of LOS among those who died is often unclear, but is important to the interpretation of the effect estimate presented.	Clearly indicate how LOS values among decedents were coded. For example, indicate if LOS was censored at the time-of-death in a time-to-event model or when reporting composite outcomes that include LOS (e.g., event-free days), clearly define the value for LOS used for those who die (e.g., zero free days).
	The analytic sample that was used to estimate the effect of an intervention on LOS is not always clear or well-defined.	Cleary state the analytic sample (e.g., survivors only) and sample size for each statistical analysis that is conducted.
	Mortality is often reported at a few discrete time points (e.g., 28 or 60 days) or without a specific follow-up period (e.g., ICU mortality). This makes it difficult or impossible to assess trials for interpretive bias in the reporting of nonmortal endpoints if non-differential mortality occurs between study arms.	Include a Kaplan-Meier survival probability figure that reports mortality rates at regular and frequent time periods (e.g., 7, 14, 21, and 28 days) that complement the follow-up time of the LOS analysis.
	Most trials do not execute sensitivity analyses using advanced statistical methods.	Although the ideal or “correct” method for statistical inference may be uncertain, using secondary methods such as competing risk, principal stratification, or joint statistical models can help researchers assess both the impact of their assumptions and the robustness of their results.