Problem Concentration Diagram

Quality in Healthcare

Problem Concentration Diagram

By Bjørn Andersen, Tom Fagerhaug, and Marti Beltz

The location where an event occurs may be important information. For instance, in which operating rooms do injuries occur? Which floors see fall accidents?

A problem concentration diagram helps you connect events to physical locations, thus perhaps revealing patterns of occurrence.

Proceed as follows:

  1. Design the diagram by drawing a map of the building, area, or system.
  2. Determine whether location-based event occurrence data already exist. If yes, skip to step 4.
  3. If not, define what events are to be recorded and collect data linking events to locations.
  4. Where more than one event is recorded, assign symbols to each.
  5. Populate the diagram with the collected data by plotting the events on the diagram.
  6. Analyze the diagram to identify patterns of event occurrences.


A long-term care facility wanted to see whether patient falls occurred randomly throughout the facility’s buildings and outdoor area or were concentrated in some areas.

The investigation team reviewed all reported falls during the last year. In the majority of these, event reports described the location of the falls. Where the exact location was missing, in most cases, the team could deduce the location from the description of the fall.

Based on these data, the team produced a problem concentration diagram. The diagram was based on a rough sketch of the buildings and grounds, indicating types of rooms (for example, bathrooms, bedrooms, corridors, stairs) and assigning different colors to different categories of rooms. The recorded falls were then plotted on this diagram.

A variation of this diagram is shown below. In the real diagram, numbers were used to identify the exact fall event, but this simplified version only uses stars to mark falls.

The team summarized the number of falls that had taken place in each particular room as well as in different types of rooms. A clear pattern emerged, with bathrooms and bedrooms seeing the most falls (and even more specifically, the immediate surroundings of toilets and beds, respectively).

Problem Concentration Diagram

Excerpted from Bjørn Andersen, Tom Fagerhaug, and Marti Beltz, Root Cause Analysis and Improvement in the Healthcare Sector: A Step-by-Step Guide (Milwaukee, WI: ASQ Quality Press, 2010), pages 65-66.

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