Instrument Reliability
They are considered to be reliable when they provide consistent results under the same conditions
Cronbach alphja
Should be greater than 0.8 indicating the reliability of a scale
Terms indicating reliability
Test-test
Instrument validity
Considered to be valid when they actually measure what they are supposed to
Power analysis
Taking the ariables of the study and doing quantitative analysis to determine how large a sample size must be
Validity of a study
Degree to which in one is justified in conclusions drawn from the study
Max drop out rate
20% - more would be a threat to validity
Internal validity
Inferences about relationships among study variables