Aims: To determine if retrospective self-report of oral parafunctional behaviors potentially relevant to pain conditions is valid, by comparing oral parafunctional behaviors via a self-report instrument (Oral Behaviors Checklist [OBC]) with in-field reports of oral parafunction. Methods: Individuals with a range of oral parafunctional behaviors, as identified by the OBC, were recruited, and 22 completed the field study. Using the Ecological Momentary Assessment paradigm, each subject was randomly prompted about eight times per day, for a target of 7 days, via portable handheld computer to report current behaviors among 11 queried items. Before and after the field study, a paper version of the OBC was administered. Separately, 74 individuals participated in a test-retest study of the paper OBC. Analyses included regression, correlation, intraclass correlation coefficient (ICC) and area under the receiving operating curve (AUC). Results: Pre- and postfield study administration of the OBC exhibited substantial reliability (ICC = 0.65), indicating no reactivity during the intervening in-field data collection. Reliability across in-field days was low, indicating high variability in which behavior occurred on which day. Nonobservable behaviors were reported more frequently than observable behaviors. Self-report via OBC was linear with in-field data collection methods (R2 values ranged from 0.1 to 0.7; most values were within 0.3 to 0.4). The predictive value of the self-report total score was AUC (0.88) relative to the in-field study score. Separate test-retest reliability of the OBC was almost perfect (ICC = 0.88). Conclusions: The OBC is a reliable and valid way to predict behaviors in the natural environment and will be useful for further pain research. Keywords: behavior, pain, parafunction, self-report, TMD