Table 9.

Comparison of pre- and post-intervention knowledge scores between trial arms

Intervention arm (n = 25)		Control arm (n = 25)		Independent t-test for mean differences in pre- and post-intervention scores between trial arms
Mean score difference (%, SD)	95% CI	Mean score difference (%, SD)	95% CI	Mean score difference (%, 95% CI)	t-value (df)	P value
4/23 (19.5, 25.6)	8.9-30.0	1/23 (4.0, 13.2)	−1.5-9.5	3/23 (15.5, 3.8-27.2)	2.69 (35.9) equal variances not assumed	0.011

Data were normally distributed and parametric tests were used.

The 95% CI values with minus signs indicate a wide standard deviation within the greater population of nurses, particularly in the control wards, indicating that the sample size may be too small.

Note: test material is available to reviewers and editors on request. CI, confidence interval, SD, standard deviation; df, degrees of freedom.