Moderators, mediators and nonspecific predictors of outcome after cognitive rehabilitation of executive functions in a randomised controlled trial

ABSTRACT

Moderators, mediators and nonspecific predictors of treatment after cognitive rehabilitation of executive functions in a randomised controlled trial

Objective: To explore moderators, mediators and nonspecific predictors of executive functioning after cognitive rehabilitation in a randomised controlled trial, comparing Goal Management Training (GMT) with an active psycho-educative control-intervention, in patients with chronic acquired brain injury.

Methods: Seventy patients with executive dysfunction were randomly allocated to GMT (n = 33) or control (n = 37). Outcome measures were established by factor-analysis and included cognitive executive complaints, emotional dysregulation and psychological distress.

Results: Higher age and IQ emerged as nonspecific predictors. Verbal memory and planning ability at baseline moderated cognitive executive complaints, while planning ability at six-month follow-up mediated all three outcome measures. Inhibitory cognitive control emerged as a unique GMT specific mediator. A general pattern regardless of intervention was identified; higher levels of self-reported cognitive—and executive–symptoms of emotional dysregulation and psychological distress at six-month follow-up mediated less improvement across outcome factors.

Conclusions: The majority of treatment effects were nonspecific to intervention, probably underscoring the variables’ general contribution to outcome of cognitive rehabilitation interventions. Interventions targeting specific cognitive domains, such as attention or working memory, need to take into account the patients’ overall cognitive and emotional self-perceived functioning. Future studies should investigate the identified predictors further, and also consider other predictor candidates.

KEYWORDS:

• Executive function
• goal management training
• cognitive rehabilitation
• randomised controlled trial
• predictors of outcome

Acknowledgements

The authors thank the participants, and the staff at the Cognitive Rehabilitation Unit Sunnaas Rehabilitation Hospital. Especially, we want to thank Brian Levine for providing the BHW material and for valuable advice throughout the research project.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Sveinung Tornås http://orcid.org/0000-0003-4821-3518

Additional information

Funding

This work was supported by the Norwegian ExtraFoundation for Health and Rehabilitation through EXTRA funds under grant number 2011/2/0204.