Exploring the truthiness in home sleep test (HST) reports.

Abstract

Recently, our sleep center reengaged the question of what standard form of wording to put in the conclusions section of home sleep test (HST) reports about the severity of obstructive sleep apnea (OSA). One staff member opined that it should merely say that the study did or did not confirm an OSA diagnosis, irrespective of AHI severity, but feared that bringing up this wording issue would open up a “can of worms.” One technologist made wording suggestions which were not accepted. The complexities across cases make any standard wording liable to charges of “truthiness” or “shallow sophistry.” The “can of worms” characterization expressed an honest anxiety about the political and philosophical complexities. In any center processing larger number of HSTs, what wording(s) can balance the dual goals of being efficient while fostering good clinical care? This “can of worms” indeed will not just go away. Resolving its political aspects will depend on the particular sleep center. However, a deeper analysis would suggest that this “can of worms” has at least two main lines of conceptual complexity for individual HST reports, irrespective of local politics. The first is about what theory(ies) of truth (i.e., validity) to utilize when working through to a study’s interpretation. While there are newer, minor variants for theories of truth, the main enduring ones are the Correspondence Theory of Truth (CORRESTT) and the Coherent Theory of Truth (COHERTT) [1]. The CORRESTT is a notion that a statement is true if it corresponds to the state of affairs “in reality.” We use this general approach in conforming to official diagnostic criteria, even when its strict observance is an oversimplification of how science works [2]. According to diagnostic criteria, if particular clinical observations are present, and fit the criteria, then the patient has the medical condition. For example, a respiratory event is scored as a hypopnea because one follows the applicable scoring criteria for hypopneas, and not otherwise. The extreme position for the CORRESTT is positivism, a position supporting summative conclusions only if positive observable evidence according to standardized rules of observation is present. But under such an extreme positivistic standard, the apnea-hypopnea index (AHI) estimated from an HST cannot support any OSA diagnosis, since the rules for the HST are not those for the polysomnogram (PSG). This extreme kind of positivism is long out of date, although sometimes still proffered because it emphasizes observational reliability. While using standardized scoring criteria is highly important for inter-rater reliability, reliability is not the only aspect of validity. By contrast, the COHERTT states that a statement can be considered true when it is in general coherence with the real situation. This kind of truth assessment is not based on abiding strictly by a fixed set of rules but is more applicable in ambiguous fact situations where a reasoned judgment is required about where the truth lies. The current controversy about whether those patients with AHI 5 according to the American Academy of Sleep Medicine (AASM) 3 % rule, illustrates this point. Do such CMS 4 %-negative patients “not have” OSA? Applying CMS rules strictly by the CORRESTT, no; but this conclusion is absurd. Of course that patient has OSA, especially if the AHI is greater than 30 per AASM criteria! It is simply false (compellingly by the COHERTT) that that patient does not have OSA. While we are waiting for the 4 % rule to be * Douglas E. Moul mould@ccf.org