Keyword Analysis & Research: what are threats to external validity

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
what are threats to external validity	0.1	0.7	6918	11	37
what	1.87	0.8	4820	52	4
are	1.25	0.3	4961	41	3
threats	1.11	0.5	2769	51	7
to	0.38	0.2	6412	40	2
external	1.48	0.5	6835	65	8
validity	0.54	0.6	7668	5	8

Keyword	CPC	PCC	Volume	Score
what are threats to external validity	0.01	0.4	8701	8