Funnel Charts

Funnel plots are a popular tool for identifying outliers when comparing measurements from multiple organisations or establishments. These charts allow you to identify whether a given unit is likely to be statistically different from the others, after accounting for the uncertainty due to differing/limited amounts of observations, by drawing "control limits" within which 99.8% of observations are expected to fall. The visual is implemented purely within PowerBI and has no dependencies on external programs like R or Python. The visual natively supports tooltips as well as cross-plot filtering and highlighting. The following chart types are (currently) implemented: - Proportion - Indirectly-Standardised Ratios - Ratio of Counts (Rates) The visual also provides an additive adjustment for overdispersion, as discussed in: Spiegelhalter DJ. Handling over-dispersion of performance indicators. BMJ Quality & Safety 2005;14:347-351. https://qualitysafety.bmj.com/content/14/5/347