Fig 3. Results of questionnaire on usability.

The median (range) score per question are: Q1, 1 (range 1–1); Q2, 1 (1–2); Q3, 1 (1–5); Q4, 1.5 (1–3); Q5, 1 (1–5); Q6, 2 (1–5); Q7, 1 (1–2); Q8, 1 (1–2); Q9, 1 (1–2); Q10, 2 (1–4); Q11, 1 (1–2). *Indicates statements that were posed in terms of difficulty of use, rather than ease of use. Here they have been inverted, in order to facilitate comparability across all the statements.