UK SSP and work schedule

Summary:

Is Statutory Sick Pay Schedule mandatory for calculating SSP payments? In the document it is stated that

'To enable the accurate processing of absences, a schedule must be available for the employee being processed. If one hasn’t been specified (or not found), the application uses the employee’s work schedule (which again can be associated at different levels of the organization). Users can create an alternative work schedule to that which the employee normally uses for calculating SSP payments.'

That means we need some work schedule for calculating SSP ? Is it possible to calculate SSP without work schedule?