LibQUAL+(TM) How to Read Thermomoter Charts

How to Read Thermometer Charts

The LibQUAL+TM survey asks participants to assess the quality of library service delivery using three criteria:

• Perceived service level – what the user sees
• Desired service level – what the user wants
• Minimum acceptable service level – the lowest acceptable level of service

Thermometer charts allow analysis of these three criteria in relation to each other:

• Green boxes on the charts = perceived service level
• Top of the blue bar = desired service level
• Bottom of the blue bar = minimum acceptable service level.

Looking at these three data points together facilitates a clearer understanding of how our users feel about our services than looking at each of them in isolation.  For example, a perceived score of 6.3 on a 9 point scale might be interpreted as average.  However, if the minimum acceptable service level is a 3.1 and the desired service level is a 7, then we are doing very well.  Our performance is close to what the user desires.  On the other hand, if the minimum acceptable service level is a 3.1 and the desired level is 8.2,  the assessment that users view our performance as average would be accurate.