Introduction
This article will show you how to get the most out of your tracker study and see how responses change over time.
Requirements
Two wave variables stored in different files.
Method
In order to compare the results in two different waves of a tracker it is necessary to combine the two different waves into a single data file. The best way to do this is to extract a single data file from the data collection software, containing both waves of the tracker and a variable time-stamping the time of interviews.
Alternatively, it is possible to merge two data files together using Tools > Merge Data Files > Add New Cases, although this should in general be avoided as:
- It can be difficult to manually construct a Date variable.
- It can be difficult when questionnaires have changed between waves.
- It requires the person doing it to have a good understanding of data (as ill-considered decisions can have large ramifications).
Once the a single cumulative data file has been obtained, it is imported into Q using File > Data Sets > Update.
Finally, results between the waves are tested by selecting a variable indicating wave in the Brown Drop-down Menu.
Also See
How to Build Tables that Automatically Show Results from the Latest Period
How to Work with Date Questions With Irregular Time Periods
How to Set Up a Data File for Tracking Studies