Diagnostic Anchoring

The DSM-5 outlines a disorder should "not better explained by" alternative reasons. But what happens to those other explanations when a diagnostic label enters the competition? When do they win? And when do they lose? From insight evaluations and competency determinations to the diagnostic process itself, a psychiatric diagnostic label reorganizes experiences (evidence) under a central explanation (hypothesis). This study proposes the idea of an essentialist-coherence structure of diagnostic categories that gives them a unique advantage in the explanatory competition. Haslam et al. (2000) articulated that people perceive psychiatric categories as being informative, uniform, inherent, and exclusive. Interestingly, these perceived properties map well onto Thagard's (1989) theory of explanatory coherence. This theory states that, when people evaluate competing explanations, 1) we prefer a hypothesis that explains more pieces of evidence than other hypotheses 2) does so under a single explanation (as opposed to multiple explanations), the combination of which results in 3) one explanation becoming more dominant, inhibiting alternative explanations. In this theory, Thagard's breadth corresponds with Haslam's informativity, simplicity corresponds to uniformness and inherence, and inhibition corresponds to exclusion. It is perhaps the case that the perceived essential properties give a psychiatric category an advantage in an explanatory competition. While research on labelling effects is, it primarily focused on stigma or the downward attitudinal consequences of a psychiatric label, rather than the mechanisms that might produce or maintain them. Thus, this study seeks to provide a theory as to the architecture whereby a diagnostic label reorganizes experience and lay explanation. The present study proposes the idea of diagnostic anchoring as this mechanism. Diagnostic anchoring is a social cognitive process whereby the culturally scaffolded beliefs about the essentialist properties of a psychiatric diagnosis get recruited by explanatory networks, providing it an advantage in the explanatory competition. This concept is different from attribution theory and stigma research as it is not concerned with causal direction or attitudinal effects, but the dominance of a single, diagnostic explanation. I posit that the properties of a diagnostic label allow it to 1) account for a broader range of evidence (explanatory breadth) 2) do so through a (relatively) single node alone (simplicity), which 3) inhibits other competing explanations. In sum, when a diagnostic label is applied and "wins," I predict the explanatory field is anchored around, or collapses into the diagnosis. I plan to test this theory using an online survey employing vignette methodology and rhetorical structure theory (RST) analysis on Python.