Question 1: Using SPSS, cross-tabulate outcome by treatment group and carry out a chi-squared test of linear association.
We choose Analyze, Descriptive Statistics, Crosstabs. Put the variable 'Radiological assessment' into Row(s): and 'Treatment' into Column(s):. Click Statistics, Chisquare, Continue. Click OK.
You should get the case processing summary and then the following:
|Radiological assessment * Treatment Crosstabulation|
| Radiological |
|No material change||2||3||5|
|Value||df|| Asymp. Sig. |
|N of Valid Cases||107|
| a 2 cells (16.7%) have expected count less than 5.
The minimum expected count is 2.43.
The linear association test gives chi-squared = 17.761 with P = .000, which we should write as P < 0.001.
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Last updated: 15 November, 2006.
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