Skip navigation

Hi all, my name is Nicolas and I am a Graduate Analytics Consultant at Concentra. I'd like to share with you this dashboard on obesity admission episodes in England and the process I used to create it. If you're not familiar with Level of Detail expressions, check out my blog on the different types of LODs and their use cases before you go on reading.


After building a visualisation on Europe’s religious groups which would demonstrate a use case for Tableau’s Level of Detail expressions, I decided to create a blog using healthcare data to show how the same functionality can be applied to a range of topics.

The subject matter I chose to visualise was obesity rates in England, or more specifically hospital admission episodes with a primary diagnosis of obesity in England, by Local Authority in 2014/15. The dataset I used was the “Statistics on Obesity, Physical Activity and Diet – England 2014/15” published recently by the Health & Social Care Information Centre (HSCIC).

Click on a local authority in the dashboard below and explore for yourself:


  • This dashboard was made possible with the following calculated field: “Total Number of Admissions by Gender”:



     This Fixed LOD works out the sum of people admitted to hospital with a diagnosis of obesity grouped by gender, regardless of what other dimensions are in the view. This is      an application of Proportional Brushing: the Fixed LOD lets you compare the selection (admissions in selected local authority) to the total amount (admissions in England).


     This is plotted in the fact boxes on the left:


  • Once this is calculated it is possible to work out the total number of admissions by gender, as a Percent of the TOTAL number of admissions, with the following calculated field:



    The result is plotted on the bar chart on the right:


  • The tooltips can also be exploited to add dynamically changing information according to which selected LA has been selected. Explore them and find out the number of admissions relative to the population of each LA.


     If you’d like to know more about the different kinds of LOD Expressions, Tableau offers some very useful resources around the topic: take a look at its “Understanding LOD      Expressions” white paper or the interesting list of example it created in its "Top 15 LOD Expressions" article.