Background Effective teamwork facilitates collective learning, which is integral to safety culture. There are no rigorous evaluations of the impact of team training on the four components of safety culture—reporting, just, flexible and learning cultures. We evaluated the impact of a year-long team training programme on safety culture in 24 hospitals using two theoretical frameworks.

Methods We used two quasi-experimental designs: a cross-sectional comparison of hospital survey on patient safety culture (HSOPS) results from an intervention group of 24 hospitals to a static group of 13 hospitals and a pre-post comparison of HSOPS results within intervention hospitals. Dependent variables were HSOPS items representing the four components of safety culture; independent variables were derived from items added to the HSOPS that measured the extent of team training, learning and transfer. We used a generalised linear mixed model approach to account for the correlated nature of the data.

Results 59% of 2137 respondents from the intervention group reported receiving team training. Intervention group HSOPS scores were significantly higher than static group scores in three dimensions assessing the flexible and learning components of safety culture. The distribution of the adoption of team behaviours (transfer) varied in the intervention group from 2.8% to 31.0%. Adoption of team behaviours was significantly associated with odds of an individual reacting more positively at reassessment than baseline to nine items reflecting all four components of safety culture.

Conclusions Team training can result in transformational change in safety culture when the work environment supports the transfer of learning to new behaviour.