Social desirability and sustainable food research: A systematic literature review

Social desirability bias could affect the results of research using self-reports, like questionnaires, which are the dominant approach to explore sustainable food consumption and its drivers. Despite various methodological and statistical approaches have been suggested to counteract social desirability, their use in research about sustainable food has not been systematically reviewed before. Therefore, a systematic literature review was carried out covering 388 peer-reviewed studies. The number of papers mentioning social desirability bias steadily increased since the 1990s. However, our results indicates that the overall proportion of relevant papers discussing it is low, with most of those doing so giving no clear indication about its causes and/or consequences for data quality. Moreover, few studies provide information about the data collection process, despite well-known situational factors influencing social desirability bias. A few papers implemented methodological remedies, like anonymity or proper scaling. Statistical remedies, like social desirability scales, were found in two studies only. Our findings suggest three major improvements in survey research about sustainable food. First, a better description of the data collection process is recommended, to better identify the limitations and strengths of a specific study. Second, procedural remedies against social desirability, which are now the gold standard in other survey-based disciplines, should be used more consistently. Finally, more research is needed adopting social desirability scales, which are relatively common in other fields of research using surveys (e.g. dietary studies), as well as specialized questioning techniques for sensitive answers.