Absence is a management issue, not a medical one. That is why similar organisations with similar work profiles can have very different absence levels. The difference is not that the employees in one company are more ill. The difference is that one company is managing absence better than the other one.
Any absence is a cost to the employer, regardless what the line of work or sick pay policies. And if absence is not measured, it can’t be managed. Therefore, it’s always recommended to start recording absence ideally before it becomes a problem. However, if you’re looking for a solution to turn around a culture of poor attendance, it is never too late to start.