A roster can show planned working patterns: when duties start and finish, time between duties, night work, long shifts and runs of days. It cannot establish how long someone slept, how tired they feel or what caused an incident.
Start with what the file actually contains
A planned duty is evidence of a plan. It is not automatically evidence of hours actually worked. Cancellations, overtime, shift swaps and work at another site may change the picture. Keep those distinctions when reviewing a finding.
RosterWise checks working patterns using fixed rules. Its Schedule Risk score is an additive review score, not a measurement of sleep or an individual’s physiological state. The Evidence and limitations page explains the references and the thresholds chosen by RosterWise.
Example: the first shift of the week
A synthetic roster starts on Monday with a duty at 07:00. There is no Sunday shift in the file. That alone does not establish that the person had Sunday off: Sunday may simply sit outside the supplied period.
Supply the relevant earlier work and confirm any work outside the roster. Until the necessary evidence is present, the affected checks should remain unknown. In RosterWise this is shown as Limited data, rather than a clean result.
A useful finding shows its limits
- The start and finish times behind the flag.
- The rule or reference used.
- The context that was supplied and what is missing.
- The operational question a manager needs to investigate.
For example, a short turnaround can prompt a review of the planned duties and the person’s circumstances. It does not establish the number of hours they slept. Time off includes any travel, caring responsibilities and other activities; those cannot be reconstructed from shift times alone.
Deciding what to change
Compare a proposed change against the original pattern, rerun the checks and review missing staffing information. People remain responsible for the decision. An accepted proposal records a decision and provides a separate roster export; it does not change the uploaded roster.
Read how to compare a roster change. For the broader approach to managing shift work, see HSE’s fatigue guidance.