Inter-rater Reliability in Assessing Exercise Fidelity for the Injury Prevention Exercise Programme Knee Control in Youth Football Players

Abstract

Background To receive maximum benefits from injury prevention exercise programmes (IPEP) such as Knee Control , players need to perform the exercises as prescribed. But, exercise fidelity in IPEPs is seldom evaluated. We developed a checklist to assess exercise fidelity in the Knee Control IPEP, and the primary aim was to evaluate its inter-rater reliability. The secondary aim was to study Knee Control exercise fidelity in youth football players and compare sex differences. Methods This observational study included 11 teams with male and female youth players (11–18 years). On average, the players trained with the Knee Control IPEP for 7 weeks (SD 1.4, range 6–10 weeks). After the training period, two physiotherapists attended a team training session to observe players executing exercises and individually assessed their performance of these exercises as correct or incorrect based on standardised criteria set in the fidelity checklist. Agreement between observers was assessed using Cohen’s kappa coefficient. Results The observers agreed on 144 out of 160 (90%) observations (Kappa = 0.80, substantial agreement). Both observers agreed on correct exercise performance for 69 out of 144 observations (exercise fidelity 48%). Exercise fidelity was higher in females (56%) than males (40%), but the difference was not statistically significant ( p = 0.18). Conclusion The Knee Control exercise fidelity checklist had high inter-rater reliability with substantial agreement. The exercise fidelity was low, which could hamper the preventive effects of an IPEP. Understanding the reasons for low exercise fidelity is important and more effort should focus on increasing exercise fidelity alongside the implementation of IPEPs. Electronic supplementary material The online version of this article (10.1186/s40798-019-0209-9) contains supplementary material, which is available to authorized users.

Injury Prevention in Youth Football Players : Training Effects and Programme Implementation

“…When used in rehabilitation progression should be made individually, based on each patient's neuromuscular control and movement quality 2 . In the IPEPs used in team sports, the neuromuscular training is usually team-based and progressed for the whole team at the same time for practical reasons 66,92,[147][148] . During all exercises, the quality of the movements should be emphasised 2 .…”

“…A study of female youth football reported that some players did not concentrate upon the execution of the exercises 157 . Recently, the exercise fidelity in football teams using the Knee Control IPEP has been studied using a checklist 92 . Overall, only 48% of the observed exercises were performed correctly, which may reduce the preventive effectiveness of the IPEP 92 .…”

“…Recently, the exercise fidelity in football teams using the Knee Control IPEP has been studied using a checklist 92 . Overall, only 48% of the observed exercises were performed correctly, which may reduce the preventive effectiveness of the IPEP 92 . Another implication of these results is that coaches need more support for instructing the players in the IPEP and for supervising and correcting technique flaws 92 .…”

“…If exercise fidelity proves to be important for the effect, this figure is reduced even further. We know that exercise fidelity in a similar context using the Knee Control IPEP was around 50% 92 . One reason behind these difficulties may be that a coaching behaviour change is needed.…”

“…Another limitation was that exercise fidelity was not assessed. An exercise fidelity checklist was recently developed as a tool for registering whether the Knee Control exercises were carried out using the correct technique or not 92 . This information would have been valuable when interpreting the results of Studies I and IV.…”