Preliminary efficacy of pharmacological treatments on sluggish cognitive tempo (cognitive disengagement syndrome): a systematic review and meta-analysis

Objective Sluggish cognitive tempo (SCT), also referred to as cognitive disengagement syndrome (CDS), is characterized by symptoms such as mental fogginess, slowed behavior, daydreaming, and reduced alertness. It is increasingly recognized as a construct distinct from attention-deficit/hyperactivity disorder (ADHD). This systematic review and meta-analysis aimed to evaluate the effectiveness of pharmacological interventions on SCT/CDS-related outcomes. Methods A comprehensive literature search was conducted in PubMed, Scopus, and Web of Science. Studies assessing pharmacological treatments with reported SCT/CDS outcomes were included. The primary quantitative synthesis focused on randomized controlled trials and crossover designs, while open-label studies were analyzed qualitatively. Standardized mean differences (Hedges’ g) were calculated using a small-k-robust random-effects model (Paule–Mandel τ² estimator with Hartung–Knapp adjustment). A 95% prediction interval was additionally reported. Results A total of seven studies were included in the qualitative synthesis, of which three (43%) provided sufficient data for meta-analysis. The total sample sizes of individual studies were generally small, contributing to limited statistical power. Using a small-k-robust random-effects model (Paule–Mandel τ² with Hartung–Knapp adjustment), the pooled effect was g=0.39 (95% CI: 0.01–0.78). The 95% prediction interval was −0.06 to 0.85. Between-study heterogeneity ranged from moderate to high (I² > 50%), reflecting variability in study design, pharmacological agents, outcome measures, and population characteristics. Discussion Preliminary evidence suggests that pharmacological treatments, particularly atomoxetine and methylphenidate, may be associated with moderate improvements in SCT/CDS symptoms. However, given the limited number of controlled trials and the heterogeneity in populations (e.g., ADHD with comorbid dyslexia), these findings should be considered exploratory. Further large-scale RCTs are necessary to confirm these results and establish personalized treatment protocols.