*4.4. Limitations and Future Directions*

The current study provides essential information about the psychometric properties of social cognition and social behavior measures in DS, but it also has limitations. First, the rates of ASD in our study sample were lower than what has been reported in other studies examining the prevalence of ASD in DS, and additional work is needed to determine if these measures are appropriate for participants with DS and co-occurring ASD. There is also a need for a longer follow-up period to determine how these measures assess social constructs over 6 months or a year, to match the study design of a clinical trial. Examining the psychometrics of the measures in groups of children within narrower age ranges will also be an important step for future research. Additionally, social behavior was only measured using parent-report, and while it is valuable to understand the comparison between direct assessment and parent-report, this study did not include any direct assessments of social behavior. Because the NEPSY-II laboratory-based assessments were not correlated with the SRS-2 Social Cognition and Social Awareness, additional work is also needed to determine the generalizability of NEPSY-II subtests to real-world contexts. Finally, because few standardized clinical assessments focus on social cognition, further examination of a greater variety of social cognition laboratory-based measures is needed to ensure that the measures appropriate for the general population [29,31] are also suitable for individuals with DS. This future work would help to identify additional alternatives for measuring social cognition and social behavior in DS.
