Discussion
humour, dry mouth, far-advanced disease, bad mood
DRY MOUTH
Although we had already simplified the intervention after the pilot test and reduced the number of intervention appointments, still only a very small proportion of palliative care patients were eligible, and even fewer were able to provide sufficient data from the first intervention. This phenomenon of high attrition rates has been reported in palliative care previously [Even though the analysis of variance did not show a significant effect of the intervention in the pre- and post-comparison, the comparison of pre- and post-data between the intervention and control group presented some promising results despite the small sample size. Whereas there were no significant changes in the control group, the perceived level of stress, seriousness, and bad mood were reduced in the intervention group, and cheerfulness increased. The positive effects of the humour intervention were supported in the qualitative analysis of the field notes. However, Bland and Altman [In the intervention group, life satisfaction was slightly lower after the intervention, in contrast to the positive findings for level of stress, seriousness, bad mood, and cheerfulness. A possible explanation could be that completing the questionnaires might have had a negative effect on patients’ life satisfaction. This effect has been reported in literature in the past [Our study confirmed that short and simple assessment instruments are a mandatory precondition for palliative care research. However, evaluation of the effectiveness of humour interventions in patients with far-advanced disease might require proxy-reported instead of patient-reported outcome measures and observational assessment instruments as well as suitable biomarkers. Again, problems with sampling have to be considered, such as the high frequency of dry mouth or swallowing problems which can interfere with saliva sampling.