Among UK adults who have had therapy, 27% did not find it helpful (BACP/YouGov 2025, n=5,150); among US adults who have never sought mental health care, approximately 33% express latent demand — they want care but have not pursued it (APA/Harris Poll 2025, n=1,076). The bilateral comparison is directionally consistent with Gilovich and Medvec’s inaction-dominance model, but the 6-percentage-point gap is computed from incomparable populations — UK therapy-attenders versus US non-attenders — and should not be read as a precise effect size. The pattern is classified as balanced: the signal points toward inaction carrying more regret, but the cross-national measurement gap prevents a stronger directional claim.
The data-quality limitations are layered. The action-side BACP figure is the stronger instrument: a large, nationally representative YouGov survey asking therapy-attenders to assess their own outcomes. Its weakness is framing — “not helpful” captures a broad range of outcomes from genuine harm to mild disappointment, and the 27% unhelpfulness rate sits well above the 5.2% lasting-harm rate found in Crawford et al.’s NHS patient survey (n=14,587), confirming that most of the 27% experienced disappointment rather than lasting damage. The inaction-side rate is a derived figure: 17% of all US adults said they want mental health care but have not sought it, out of 51% who had never sought care, yielding 33% latent demand among non-attenders. Latent demand is prospective (want to go) rather than retrospective (wish I had gone), which likely understates actual regret in older cohorts where the opportunity cost has already accumulated.
Two structural confounders qualify any strong directional claim. First, access barriers make much inaction involuntary: NHS England waiting lists, US insurance gaps, cost, and persistent stigma mean that a share of non-attenders who want care cannot readily obtain it, conflating structural barriers with personal decision regret. Second, cross-national asymmetry in the data — UK for the action side, US for the inaction side — introduces noise because NHS cost-free access and US insurance-dependent access produce different selection effects in who enters therapy and who doesn’t. Within those limits, the data are consistent with the established finding that long-run regret accumulates more on the side of inaction than action, though the effect size here is too small to carry strong causal weight.