Statistical Procedure

This procedure can be used when the:

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

Present this graphically using a Error Bar scatterplot or Box and Whisker Plot

In SPSS select: Graphs > Chart Builder - Gallery – Scatter | Simple Scatter or Boxplot | Simple Boxplot

Use Element Properties to change the Statistic for the Y axis to Mean and tick Display Error bars

Analyse this in SPSS using:

Analyze >General Linear Models > Repeated Measures

Report this quoting the:

95% Confidence Intervals and p-value

Comments

See the paper by Matthews et al BMJ (1990) vol 300 p230, Analysis of serial measurements in medical research

References

Chapter 13, p 468 in Discovering Statistics using SPSS 3rd Edition, A. Field, Sage Publications (2009) (ISBN: 9781847879073)

Please Report any issues to Brian Yuen