Alterman et al. (2004) compared the effect of an eight-week (23 hour) MBSR course
with treatment-as-usual for 31 substance-abuse recovery inpatients at postintervention and at five months follow-up (Alterman, 2004). The data were analysed
using repeated measures analysis of variance at three time points. The intervention
26 The Campbell Collaboration | www.campbellcollaboration.org
group improved more than the control group in terms of self-reported medical
problems when analysed as a group over three follow-up times (p=0.007). However,
because only mean values were reported, a Hedges’ g-value of effect size could not
be calculated. No significant group differences were found for measures of
psychological health.