PPT Slide

COMPARISON OF RANDOM GROUPS (RG) DESIGN VS. ONE-GROUP,

PRETEST-POSTTEST (OGPP) AND STATIC GROUPS COMPARISON

(SGC) DESIGNS IN TERMS OF APPLICABILITY OF CAMPBELL AND

STANLEY’S ORIGINAL SEVEN THREATS TO INTERNAL VALIDITY

RG OGPP SCG

HISTORY No Yes No

MATURATION No Yes No

TESTING No Yes No

INSTRUMENTATION No Yes No

REGRESSION No Yes No

SELECTION No No Yes

MORTALITY No No Yes

Note : “Yes” means the threat is unavoidable