Colagiuri, B., & Zachariae, R. (2010). Patient expectancy and post-chemotherapy nausea: A meta-analysis. Annals of Behavioral Medicine, 40, 3–14.
To evaluate the relationship between patient expectations of postchemotherapy nausea and subsequent reports of nausea
Databases searched were MEDLINE, PsycINFO, and CINAHL.
Search keywords were expectancy, expectations, placebo effects or placebo responses with chemotherapy and nausea or emesis.
Studies were included if they
Studies were excluded if they focused only on anticipatory nausea.
The authors independently coded the sample characteristics, the independent and dependent variables, and whether the study met the inclusion criteria for each study. Differences were discussed, and a final assessment negotiated for each study. A global effect size was calculated for each study. No formal scoring was used to assign a quality score to each study. Publication bias was addressed using the Egger test and calculations of failsafe.
This meta-analysis confirmed that nausea expectations and experience of post-chemotherapy nausea are positively correlated. The discussion also identified research methods, such as incorporating expectancy-based manipulations that consider the source of the patient’s expectations, actively investigating the possible moderators of the association between expectancy and post-chemotherapy nausea (e.g., age, anxiety), and measuring the expectancies before the first chemotherapy administration.
Prechemotherapy assessment needs to include patient expectations regarding the experience of postchemotherapy nausea. If a patient expects that he or she will experience nausea, additional evidence-based interventions to minimize nausea should be used prior to and during chemotherapy administration.