Figure 1.

Observed levels of skillfulness of individual naturalistic developmental behavioral intervention (NDBI) strategies by speech-language pathologists (SLPs). SLPs implemented developmental strategies at significantly higher levels of skillfulness than behavioral strategies, according to ideal NDBI strategy standards as defined on the NDBI-Fi. Average scores across SLPs did not reach high levels of skillfulness traditionally used in clinical trials (i.e., 4 out of 5 points on the NDBI-Fi), although many SLPs did reach this threshold on individual developmental strategies. NDBI-Fi = Naturalistic Developmental Behavioral Intervention–Fidelity Rating Scale (Frost et al., 2020).