Nixon et al. [ 14] presented strategies of imputing missing end points from a surrogate.
Multiple imputation was performed by using the logistic regression approach for patients with missing primary end point data (29 DCB, 7 PTA).
In the Rosiglitazone Evaluated for Cardiovascular Outcomes in oral agent combination therapy for type 2 Diabetes (RECORD) study, vital status was unknown in 2.9% of patients and a further 394 (8.9%) were alive but withdrew from some study visits, thereby missing complete CV end point information (19).
Panelists voting against approval said they were worried that the two-year phase II trial of Pulminiq included too few patients (just 56, all drawn from a single center), and that the trial missed the primary end point of acute rejection.
Missing information for any end point data or study details was requested directly from authors.
If data are missing for the primary end point because patients do not attend for follow-up at 3 months, visual acuity data will be extracted from patient records and inputted for the primary analysis.
The primary analysis was based on the modified intent-to-treat population (all randomized subjects who received one or more doses of study drug) with a last observation carried forward approach to impute missing data at the end point.
Worried that they might be missing important human end points by relying on established inbred strains in research, Threadgill and other scientists created the Complex Traits Consortium (CTC) with a mission, he says, "to reinvent the mouse model so that it would contain genetic variability on the scale of what exists in humans".
As the time gap between cyt. c release and caspase activation is known to vary significantly between cells, it is quite possible that rare events are likely to be missed in end-point assays.
Sample size calculations have been adjusted accordingly to account for this level of missing data for the primary end point of the study.
In case of missing data for the composite end point score, the worst-case scenario will be assumed for the primary analyses.
