Patient expectancy and post-chemotherapy nausea: a meta-analysis.
BACKGROUND
Post-chemotherapy nausea remains a significant burden to cancer patients. While some studies indicate that expecting nausea is predictive of experiencing nausea, there are a number of conflicting findings.


OBJECTIVE
The purpose of this study was to conduct a meta-analytic review to determine the strength of the relationship between expectancy and post-chemotherapy nausea.


METHODS
The findings from 17 relevant studies (n = 2,400) identified through systematic searches of Medline, PsycInfo, and Cinhal were analyzed using a combination of meta-analytic techniques.


RESULTS
Overall, there was a robust positive association between expectancy and post-chemotherapy nausea (ESr = 0.18, equivalent to Cohen's d = 0.35), suggesting that patients with stronger expectancies experience more chemotherapy-induced nausea. Although weaker associations were found in studies employing multivariate analysis, specifically controlling for a history of nausea, and involving breast cancer patients, none of the moderators assessed were statistically significant.


CONCLUSIONS
These findings suggest that patient expectancies may contribute to post-chemotherapy nausea and that expectancy-based manipulations may provide a useful intervention strategy.
Colagiuri
Ben
B
School of Psychology, A18, University of Sydney, Sydney, NSW, 2006, Australia. benc@psych.usyd.edu.au
Zachariae
Robert
R
D000970:Antineoplastic Agents / Q000009:adverse effects*; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D009325:Nausea / Q000139:chemically induced*; D009369:Neoplasms / Q000188:drug therapy
D000970:Antineoplastic Agents