external validity and generalisability

Question 1

what is external validity

Answer 1

how well do findings from sample apply to population and to different settings

Question 2

what are the three components of external validity

Answer 2

generalisability

applicability

replicability

Question 3

what is population generalisability

Answer 3

how well do sample results apply to population from where they were drawn

samples should be representative (larger samples likely to be more representative

should measure participant demographics so that sample is broadly in line with the population of interest

Question 4

what is environment generalisability

Answer 4

how well do results apply to different regions, areas or countries?

consider social make-up and infrastructure of areas studied in

Question 5

what is temporal generalisability

Answer 5

do results apply to different time periods

Question 6

what is applicability

Answer 6

how relevant are the findings to the real world

experiments are generally tightly controlled, but the real world is not

Question 7

what is replicability

Answer 7

repeating the study and getting the same result

direct replication - repeating with different sample from same population

replication with samples from different populations can assess external validity

Question 8

what are implications of the replication crisis

Answer 8

• lack of reliability
• lack of trust
• clinical or legal consequences