Objective Metacognitive therapy and one of its treatment components,
the attention training technique, are increasingly being
delivered to improve mental health. We examined the efficacy of
metacognitive therapy and/or attention training technique on mental
health outcomes from single-case studies.
Method A total of 14 studies (53 patients) were included. We used
the d-statistic for multiple baseline data and the percentage change
index to compute the effect sizes.
Results Metacognitive therapy has a large effect on depression, anxiety,
other psychopathological symptoms, and all outcomes together.
Effect sizes were significantly moderated by the number of sessions,
the severity and duration of symptoms, and patient gender, but not
by study quality or attention training technique when used as a
stand-alone treatment. At the follow-up, 77.36% of the individuals
were considered recovered or had maintained improvement.
Conclusion Metacognitive therapy and attention training technique
strongly contribute to improving mental health outcomes. This study
effectively informs evidence-based practice in the clinical milieu.