Effect of interventions on the size of bruising
The results of ANOVA, using a post hoc Tukey’s Honestly Significant Difference (HSD), for the
size of the bruising demonstrated significant differences between the groups. The average size of
bruising in the cold pack group and the cold–hot pack group were significantly less (p < .001) than
the size of the bruising in the control group. Additionally, no large bruise was observed in the
patients of the cold–hot pack group at any of three times (Table 2).
The percent of ‘no bruise’ in the cold pack group at 48 and 72 hours (26.7% and 46.7%) was
much lower than this amount in cold–hot pack group (55.0% and 78.3%) after injections (p
< .001). However, at 24 hours after the injection, the average bruising size between the cold
pack group (70%, 1.57 ± 0.09 mm) and cold–hot pack group (88.3%, 1.22 ± 0.07 mm) were
similar and there was no statistically significant difference between them (p = .19). But the
cold–hot pack group had significantly less (in number) and smaller (in size) injection site bruising
than the two other groups at 48 and 72 hours (both p < .001).