Cross-cultural psychology employs research methods common to most areas of psychology in the process of developing an objective quantitative field of study. The most common method used is testing for psychological differences utilizing established psychological instruments in two or more cultures (Van de Vijver & Leung, 1997a). Issues of equivalence as noted above remain an important concern to ensure valid comparisons. The surveys employed can be open-ended where the researcher asks the respondents for opinions or attitudes on particular subjects or issues. In open-ended surveys responses are not structured as participants can provide whatever responses seem correct. The researcher can tabulate the frequency of response categories as an index of response patterns, but in practice open-ended questions are more difficult to interpret. Multiple choice tests or multiple response category surveys are used more frequently and easier to quantify. Structured response categories however are also problematic as not all cultures have experiences with paper and pencil formats, nor familiarity with the topic investigated. Since the respondent must provide an answer the results can be quiet meaningless when the subject matter is not understood. However, pretesting of surveys with the target population can eliminate some of these concerns.
Surveys can also be conducted by way of interviews. Since the interviewer is present with the survey participant he/she can respond and provide any necessary clarifications. In interviews careful watch must be kept to provide standardized questions, and prevent bias by not reinforcing certain responses nonverbally or otherwise. Today surveys can also take the form of telephone canvassing or by utilizing the Internet. Telephone or Internet surveying are typically easy to conduct and low in cost. However, bias in sampling becomes a major problem as typically respondents who participate are also those that are motivated because of pre-existing attitudes at opposing ends of the attitude continuum. As a result survey participation might be narrowed to those who have a special interest in the subject. There are also socio-economic bias in distance surveying since in some countries the possession of a telephone reflect higher wealth and status. A greater problem is the social desirability factor since some issues are sensitive and responses are confounded by the desire for social approval. Respondents concerned about social desirability will provide normative responses or seek to please the researcher by providing socially acceptable answers.
The results of cross-cultural psychology presented in published journals derive from multiple researchers and utilizes alternative methodologies in measuring similar or overlapping constructs. How to get a summary view of what is significant in these studies is difficult since research in psychology is approached from many perspectives, and with varying methodology. When different researchers are studying the same construct how can we create some summary judgment about the relationships found? Meta-analysis is a statistical method that permits researchers to analyze the many studies that are completed on a particular subject and provide an overall integration of the results. Since many studies are included the researcher can have some confidence in the summary statistic. However, we must keep in mind that only studies that are published come to the attention of the researcher, and hence meta-analysis has a bias toward studies that show ”significant” differences. This analysis of previous analyses also often represent varied methodology and utilize constructs not all conceptually the same. The resulting heterogeneity may produce overall results that are less reliable and valid.