Mental Health Training Following Combat: A Randomized Controlled Trial Comparing Group Size

Abstract

Although previous studies have demonstrated that mental health programs like Battlemind training can exert positive effects on soldiers returning from a combat deployment, questions regarding optimal group size for training delivery remain. The present study examines whether training group size is related to Battlemind effectiveness. Individual soldiers recently returned from Iraq were randomized to one of three conditions: small group Battlemind, large group Battlemind and large group stress education. Soldiers (N = 2,439) were surveyed prior to the one-hour training and again three months later (59.8% follow-up rate). Battlemind received more positive ratings than stress education, and small group Battlemind received more positive ratings than large group Battlemind. Over time, soldiers in small Battlemind also reported increases in perceived organizational support relative to those in stress education (r-squared effect size estimate of 0.2%). There were, however, no consistent significant effects for PTSD symptoms, depression, or the interaction between condition and combat experiences nor did the large and small Battlemind groups significantly differ from each other. Results confirm that a 1-hr intervention can have a small but measureable impact on soldiers over time and suggest that providing such training in small groups may be advantageous.