Parry et al. 2021 — pre-registered meta-analysis: self-report ≠ logged media use

Claim: Parry et al. (2021, Nature Human Behaviour), a pre-registered meta-analysis of 106 effect sizes, found self-reported digital media use "correlates only moderately with logged measurements" and "self-reports were rarely an accurate reflection of logged media use."

Source: Parry, Davidson, Sewall, Fisher, Mieczkowski, Quintana 2021, Nature Human Behaviour. Pre-registered, peer-reviewed.

Confidence: Verified.

Why this matters for Candid: The largest, most rigorous synthesis on the question agrees with Junco 2013 — Facebook self-report overstates logged use by ~5.6x — and it is pre-registered, removing the selective-reporting concern. The mechanism (memory + social desirability) generalises beyond Facebook; expect any "how often do you update your site / post / send emails" answer to overstate reality.