PPT Slide

Campbell and Stanley Threats to Internal Validity

Time Series Design With Nonequivalent Control Group

HISTORY No

MATURATION No

TESTING No

INSTRUMENTATION No

REGRESSION No

SELECTION Yes

MORTALITY No

SELECTION X HISTORY Yes

SELECTION X MATURATION No

SELECTION X INSTRUMENTATION Yes

CONTAMINATION Yes

HAWTHORNE EFFECT Yes

EXPERIMENTER EXPECTATION No

Note: “Yes” means threat is unavoidable