Stratified Randomization

Stratified randomization can be used to produce separate lists for different groups of patients. Suppose investigators would like a reasonable balance between two treatment groups for age group (<55 and >=55years). We will produce lists of least 100 patients and use random permuted blocks.

The blockrand library has been preloaded for this session.

Use the blockrand() function within the blockrand package to generate a list of at least 100 for two treatment arms and random block sizes between 2 and 8 for patients under 55 years. Store in under55.
Repeat for those aged over 55 years and store as above55.
Display the first few rows of under55 and above55.
Tabulate the numbers of patients assigned to each arm within each list.

Take Hint (-30 XP)

Exercise

Stratified Randomization

Instructions