C3.3.2 Types of Data


There are a number of methods for the collection and analysis of data, leading to relevant conclusions and recommendations.

Data can be in either a variable or attribute format:

  • A variable is a feature which can be numerically measured (e.g. measuring a dimension on a drawing)
  • An attribute is a feature which is either acceptable or not acceptable (e.g. checking surface finish to a sample or using a go-nogo gauge)



  • give more information
  • enable trends to be monitored
  • may require more skill to measure



  • simpler and quicker to record
  • generally require less skill to measure and record
  • but give less information than attributes!