Fact · Dictation
-0.03correlation coefficient (r)
In a 2011 meta-analysis, the effect of think-aloud, saying your thoughts while you do a task, on performance was statistically indistinguishable from zero.
Checked against its source on October 16, 2026
In the source's own words
“effect size is indistinguishable from zero (r = -.03)”
Do procedures for verbal reporting of thinking have to be reactive? A meta-analysis and recommendations for best reporting methods, Mark C. Fox et al., Psychological Bulletin, 2011, Abstract.
Open the original (DOI 10.1037/a0021663)- What it measures
- The meta-analysis compared performance during concurrent verbalization with a matching silent control condition, across nearly 3,500 participants.
- What it does not show
- The reviewed tasks were visual and nonvisual lab tasks, not essay writing, so this is not a direct test of drafting by speech.