Table 1.

Problem rating scale based on Nielsen exploratory evaluation model ⁶

Score = 0 and average intensity = 0–0.5	Without problem–no problem
Score = 1 and average intensity = 0.6–1.5	Minor problem–no need to correct the problem
Score = 2 and average intensity = 1.6–2.5	Small problem–low priority problem correction
Score = 3 and average intensity = 2.6–3.5	Big problem–high priority problem correction
Score = 4 and average intensity = 3.6–4	Serious problem–high need for problem correction