Statistical analysis plan missing data

A key aspect of the definition of analysis sets and the way that missing data is to be handled is pre-specification. Usually these points will be covered in the protocol, if not, in the statistical analysis plan. If methods are not pre-specified then there will be problems as the way that these issues are dealt with could then be data driven, or at least there may be suspicion of that. This is, of course, not unique to analysis sets and missing data, but is true more generally in relation to the main methods of statistical analysis. 

The field phase of an LSMBS is critically important. Close monitoring of shoppers by field phase study management personnel is required, especially when a sampling plan includes frequent collections, such as weekly or bimonthly. Missed, delayed, or deficient commodity samples can throw a laboratory off schedule, which in turn can adversely affect both the timeliness and the quality of the analyses. Missed, delayed, or deficient samples can also affect the study outcome and interpretation, because a statistical design typically requires a certain number of data points, each represented by analysis of a commodity sample. 

Timing of any interim analysis Reason for sample size Power of clinical study Level of significance Criteria for termination of study Procedure for missing and imused data Reporting procedures for deviations from statistical plan... 

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