Statistical Procedure

This procedure can be used when the:

Outcome (Dependent) variable is a Continuous and Normally distributed measure
Exposure (Independent) variable is Paired (related) sample - 2 time points

Present this graphically using a Line Chart

In SPSS select: Graphs > Chart Builder - Gallery – Line | Multiple Line

The data for the line chart is entered as two rows per case. Row 1 = ID, Before Code, Reading. Row 2 = ID, Post Code, Reading. In Line Chart Set color = ID, X-axis = Pre/Post Code

Analyse this in SPSS using:

Analyze >Compare Means > Paired- Samples T Test

Report this quoting the:

Mean Difference, 95% Confidence Intervals and p-value
Use the confidence intervals output by SPSS

References

Chapter 9, p 326 in Discovering Statistics using SPSS 3rd Edition, A. Field, Sage Publications (2009) (ISBN: 9781847879073)
Analysing Repeated Measures in the Statistics for the Terrified package

Please Report any issues to Brian Yuen