The data are based on measurements of SBP in the HERS study. The data set allows us to compare methods of analysis with complete data and under simulated missing data. In the data sets are missing...

The data are based on measurements of SBP in the HERS study. The data set allows us to compare methods of analysis with complete data and under simulated missing data. In the data sets are missing data indicators (miss mar for bpmisslong and miss mar1 for bpmisswide) which have value 1 to flag SBP values which should be dropped to simulate data which displays MAR missingness. In particular, year 1 values from patients with higher baseline SBP are flagged more frequently and hence will be simulated as missing. You can consult the course website for the data sets and more complete documentation and details on Stata code

Using bpmisswide,

(a) Calculate and compare the year 1 SBP (year1 sbp) for the complete data and for patients who in the simulated missingness setting would have an available year 1 SBP (i.e., miss year equal to 0).

(b) Calculate and compare the change in SBP (year1_sbp - base_sbp). What is the mean change in the full sample? What is the mean change restricted among those with available year 1 values in the simulated missingness setting (miss_year equal to 0)?

(c) Based on (a) and (b) above, how has the simulated missing data mechanism affected estimates of mean of year 1 SBP values and change in SBP from baseline to year 1?