Theme 5: preliminary indications that non-pharmacological treatment can improve sleep
Four studies examined non-pharmacological treatment for insomnia in a prison environment [45], [59], [63] and [64], reporting that sleep problems were significantly reduced over time when meditation and relaxation techniques were used. For example, meditation significantly reduced the time needed to fall asleep [45] or the number of sleep difficulties over a period of fourteen and seven-weeks respectively [63]. In particular, combined stimulus control and relaxation techniques reduced the number of nightly awakenings after both two and eight weeks post-treatment initiation [64]. However, in one study, relaxation training alone did not significantly improve sleep over two weeks [59]. It is possible that the difference in findings here was due to lack of monitoring in the frequency of the use of relaxation. All the experiments included a control group and enabled tighter control over the independent variables (e.g., permits cause and effect to be recognised). However, as with the lack of RCTs to establish the effectiveness of hypnotic medication, no RCTs were used to evaluate the effectiveness of non-pharmacological treatment on insomnia in prison. The experimental studies suffered due to small sample sizes across all experimental studies (n = 24–89 only). The first community RCT of mindfulness meditation found it to be an acceptable form of insomnia treatment that reduces total wake time [78], however no evidence is available currently to indicate its success in a prison setting. Consequently, it is difficult to conclude that meditation and relaxation techniques improve insomnia symptoms in prison without using larger sample sizes, across countries and employing RCT methodology.