Does analysis using "last observation carried forward" introduce bias in dementia research?

Molnar, Frank J.; Hutton, Brian; Fergusson, Dean
October 2008
CMAJ: Canadian Medical Association Journal;10/7/2008, Vol. 179 Issue 8, p751
Academic Journal
The article discusses the disadvantages of using last observation carried forward analysis in dementia research. Last observation carried forward is the very common technique applied in intention-to-treat analyses in trials of dementia drugs. The studies using the technique show higher dropout rates in the treatment group rather than in the control group and it rarely affirm results with other intention-to-treat analysis. Moreover, the process in which the technique is being done along with its inappropriate use in drug trials in dementia research, the source of the problem are presented.


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