Brood pattern is one part of the wider colony picture. When inspecting brood, record what you can actually see: eggs, larvae, capped brood, empty cells within the brood area and any obvious abnormalities. Photographs can provide useful context when something changes.
Avoid reducing every irregular pattern to a diagnosis. Brood appearance can be influenced by several factors, and a single inspection may not explain the cause. Record the observation, compare it with earlier inspections and create a follow-up where appropriate.
A digital history is useful because it lets you see whether a pattern is new, improving or persistent while keeping photographs and notes with the relevant inspection.