In 1983, Ekstrand et al 1 published the first randomised controlled trial (RCT) of an injury prevention programme for team ball sport. Three decades on from this landmark study, it is worth reflecting on the progress made and the current 'state-of-play' in the field of team ball sport injury prevention research. The volume of published research has grown considerably with a recent systematic review of team ball sport injury prevention exercise programmes (IPEPs) identifying over 50 published trials. 2 The scale, quality and outcomes of recent RCTs are also encouraging with a Swedish trial including over 4500 female soccer players and demonstrating a 64% reduction in the rate of anterior cruciate ligament (ACL) injuries. 3 In 2013, a subsequent subanalysis of the original Swedish RCT, published in this journal, highlighted the importance of adequate IPEP compliance in preventing injuries. The ACL injury rate was 88% lower in highly compliant players, compared to those with low compliance. 4 A 3-year follow-up, 5 also published in this journal, investigated if coaches from the original trial and others in the same target population were still using the IPEP, and found that many had modified it (74-77%) or had not implemented it regularly across the season (52-60%). Others did not know about the programme, or had chosen not to adopt it. 5
HOW BIG IS THE PROBLEM?Considering that only compliant players had a reduced injury rate in the original RCT, the results of the above implementation study are of concern and demonstrate that it takes more than the existence of an IPEP to prevent injury. Even highly efficacious IPEPs risk losing much of their effect under real-world conditions, unless they are successfully adopted, implemented and maintained. A major challenge currently facing injury prevention in team ball sports is translating the positive outcomes of RCTs into injury reductions under real world, less controlled conditions. Unfortunately, little guidance is available in the sports medicine literature to help researchers and clinicians tackle this challenge. Our recent systematic review evaluating 52 published IPEP trials using the Reach Effectiveness Adoption Implementation Maintenance (RE-AIM) framework 2 identified major gaps in the reporting of key implementation aspects, particularly those relating to Adoption and Maintenance. The proportion of trials reporting the RE-AIM's eight items of adoption averaged just 4%. The corresponding figure across the nine measures of maintenance was less than 1%. 2