An observation study carried out in 2000 (n = 430 children in vehicles) by the Institute for Vehicle Safety (IFM) revealed that two thirds of children are not properly secured in vehicles, even when child restraint systems (CRS) are employed, i.e. "misuse" can be observed. "Misuse" refers in this context to instances where children are secured incorrectly in the CRS and where child seats are not installed properly in the vehicle. At 96%, the proportion of children secured in vehicles in Germany is high, but parents still experience problems when fitting and using child seats. In particular, this concerns protection systems which require that the child seat is fitted separately using the adult seat belt in addition to the child actually being secured in the seat. Incorrect installation was observed in 60% of cases where the seat had to be secured separately in the vehicle.
The fact that the three-point seat belt is intended to provide an optimum fit for adults as well as the design of the child seats appear to cause problems when it comes to securing a CRS.
ISOFIX, a protection system that is independent of the adult seat belt, allows the child seat to be fitted securely, simply and always correctly in the vehicle. The most recent results of fitting tests at the Institute for Vehicle Safety have shown that, in comparison with the conventional method using the adult seat belt, fitting errors can be significantly reduced with ISOFIX. In practice, this means that a much higher level of protection can be expected due to the avoidance of errors in installation, since tests carried out in this context have demonstrated that misuse of child protections systems, such as the seat not being secured tightly enough, can increase load values for the child by up to 40%.
In addition to two rigid ISOFIX low anchorages, an anti-rotation device, i.e. top tether or support leg, is planned for future ISOFIX seats in Europe.