Table 1.

Seven attributes of highly valued diagnostic markers.

Construct	Premise	Rationale
Accuracy	The higher the diagnostic accuracy of a diagnostic marker, the more highly valued it is in research and clinical settings.	Diagnostic markers deemed conclusive for a disorder require > 90% sensitivity and > 90% specificity, yielding positive and negative likelihood ratios of at least 10.0 and at most 0.10, respectively.
Reliability	The higher the reliability of a diagnostic marker, the more highly valued it is in research and clinical settings.	Reliable diagnostic markers have robust point-by-point intrajudge and interjudge data reduction agreement and internal and test–retest stability of scores, each estimated across relevant participant heterogeneities.
Coherence	The greater the theoretical coherence of a diagnostic marker, the more highly valued it is in research and clinical settings.	As portrayed in Figure 1, conclusive diagnostic markers (Level IV) for each of the putative speech sound disorder subtypes (Level III) are highly valued for integrative descriptive–explanatory accounts when tied to their genomic, environmental, developmental, neurocognitive, and sensorimotor substrates (Levels I and II).
Discreteness	Diagnostic markers from discrete, on-line events are more highly valued than diagnostic markers derived from off-line tallies of events.	Speech signs that that can be spatiotemporally associated with neurological events have the potential to inform explanatory accounts of speech-processing deficits.
Parsimony	The fewer the number of signs in a diagnostic marker, the greater is its theoretical parsimony and psychometric robustness.	Each sign required for a diagnostic marker adds theoretical complexity and requires additional, multiplicative psychometric stability.
Generality	The more extensive the generality of a diagnostic marker, the more highly valued it is in research and clinical settings.	Diagnostic markers with the most extensive external validity may be used to quantify risk for future expression of disorder, expression of active disorder, and postdict severity of prior disorder.
Efficiency	The greater the efficiency of a diagnostic marker, the more highly valued it is in research and clinical settings.	More highly valued markers require the fewest tasks, equipment, examiner proficiencies, and participant accommodations and the least time and costs to administer, score, and interpret.