A tornado diagram illustrating sensitivity of the benefit-risk score to change in criteria value in the PROTECT natalizumab case study

The tornado diagram above conveys the effect of changing criteria values. A longer bar represents a less robust criterion where changing the value for that criterion would yield a larger effect in the final benefit-risk score; and vice versa for shorter bars. Colours green and red represents whether the increase is favourable or unfavourable, respectively. The end of the green and red bars away from the midline (where the two coloured bars meet) reads the benefit-risk score. With this type of technical visual representation, unfamiliar users of a tornado diagram may easily misunderstand its purpose and intended message, leading to misinterpretation or misinformed decisions.