ObjectiveTo examine retention and compliance to a novel Physical Therapy (PT) treatment among Veterans with and without executive function deficits (EFD+/EFD-). DesignThis study was a preplanned secondary analysis of an ongoing randomized controlled trial. SettingOutpatient PT at VA Boston Healthcare System (VABHS). ParticipantsSeventy-two community-dwelling middle-aged and older Veterans (mean age 72, (range 51-91); 87% male) with gait speed between 0.5 and 1.0 m/s were recruited from primary care practices. InterventionsEight-week moderate to vigorous intensity PT program. Main outcome measureVeterans’ baseline mobility, retention (dropouts), and treatment compliance and post-treatment exercise compliance to 8-week PT treatment were evaluated based on their baseline EFD status. ResultsOf the 72 participants, 22% (n=16) were EFD+. Veterans with EFD+ at baseline had worse mobility performance (Short Physical Performance Battery (SPPB), 7.7 vs. 9.5, p<0.001) and patient-reported mobility (Activity Measure for Post-Acute Care (AM-PAC), 57.6 vs. 62.2, p<0.01) after adjusting for age, gender, number of comorbidities, depressive symptoms, and pain interference. Dropout rates for EFD+ and EFD- were 44% and 25%, respectively (p>0.05). In multivariable logistic regression modeling, pain interference, depressive symptoms, mobility, and living alone but not EFD status were associated with dropping out. There was no evidence of significant differences in treatment compliance or post-treatment exercise compliance, measured by the number of attended sessions and the number of post-treatment exercise days by EFD status. ConclusionEFD+ was associated with poor baseline mobility. While the dropout rate was higher among Veterans with EFD+, we were unable to conclude whether EFD status impacts retention or compliance due to the small sample size. Further investigation is needed to determine whether EFD status may identify individuals who need additional support during and/or after rehabilitation treatment.