Table 7

Estimated between-group differences in changes over time for predicted means on the Perceived Stress Scale (PSS), with confidence intervals and chi square statistic.

Placebo vs Control

Fish oil vs Control

Fish oil vs Placebo

Estimate

2.786

6.059

3.273

95% CI sep

3.289

3.046

3.943

95% CI joint

4.692

4.345

5.625

Chi square

2.754

15.193*

2.647

* Significance determined by observed value of chi sq ≥ 3.84, the critical value of chi square for df = 1 when p ≤ 0.05 Note: 95% CI sep = 95% confidence interval considering each item separately, 95% CI joint = 95% confidence interval, considering the estimates of the three treatment groups collectively, chi sq = chi square, vs = versus, the difference between groups

Bradbury et al. Nutrition Journal 2004 3:20   doi:10.1186/1475-2891-3-20