Four levels
The first level is the participant's own rating; it is cheap and tells you only about the format. The second is learning: the same questions before and after, and if the difference is meaningful, knowledge was transferred. The third is behaviour, and it is the only real indicator: four to six weeks later, the behaviour the training was about is observed in the field. The fourth is results: the trend in incidents, near misses and non-conformities on that topic.
Why the third level gets skipped
Because it is expensive and uncomfortable; observation usually shows that the training did not stick. The reason is rarely that the training was poor — it is that the condition blocking the behaviour (time pressure, missing equipment, habit) was never addressed.
In Optifora the training record, the observation form and the incident record meet on the same person, so the trend is not carried by hand into a separate table.