My previous post touched on the immense variety one can find in China's places & people and how that can impact research.
One of the more obvious of China's variations can be found in language. The official spoken language in China, Standard Chinese, is based on dialect found in the Beijing area and is commonly referred to as Mandarin or Putonghua. While Mandarin is becoming more widespread in China, in many regions other local dialects are still commonly spoken. These local dialects can be completely unintelligible to speakers of other dialects, including Mandarin.
One of the many examples I've seen in how this can matter for research involved a previous colleague of mine who is fluent in Mandarin. Regardless of her native Chinese speaking skills, when we conducted a project several years ago in Wuhan, Hubei province we ran into significant language issues. While the participants could speak Mandarin, some were far more comfortable speaking in the local Wuhan dialect. Sometimes this lead to participants expressing frustration with the need to speak in Mandarin. Other times it meant that people would frequently slip into the Wuhan dialect. While the Wuhan dialect is more similar to Mandarin than many other dialects, it was not always comprehensible to my colleague -- obviously a problem for research purposes.
It's not only an issue of whether someone can speak Mandarin at an acceptable level. If a person doesn't feel genuinely comfortable using Mandarin they may be less likely to open up and share details that could be extremely important. Choosing a dialect for an interview in China may be as simple as determining which dialect people use most. However, for people who speak multiple dialects it may be more important to identify when they use each dialect. If the research is focused on work-related issues, it may be better for interviews to be conducted using whatever dialect is most commonly used at work, and not what is used at home with family and friends. Previous research has indicated that memory can be dependent both upon context and language. Furthermore, research suggests that people who are fluent in multiple languages can exhibit different personalities and provide different answers to questions depending on the language being used. In other words, the choice of language used in interviews could impact research results even when people are fluent in both languages.
In a city such as Shanghai there are many people from a variety of regions, so for any research studies conducted there it may not be practical to conduct each interview in a different dialect if research participants are diverse. For a number of research purposes it can be appropriate to only use Mandarin given that it is commonly used at work places and in social settings in Shanghai. Such decisions depend on who and what is being researched. However, particularly when conducting research in other cities in China which may be more homogenous and where Mandarin is less often used, including an interpreter or researcher who can speak the local dialect can be crucial. For example, one large project I conducted at Microsoft included 5 different interpreters -- one for each of the cities we were exploring. Although this may mean sacrificing in terms of the quality of the interpretation (finding a top-notch translator for some local dialects can be much more challenging than finding one for Mandarin), for some types of research allowing people to speak in the most appropriate language is paramount.
While Mandarin is certainly becoming more widespread in China, particularly in younger people, it may not only be a barrier for research, but prove to be entirely unusable. Companies can't necessarily do away with needing interpreters for research work simply because they have a single Chinese-speaking researcher. It may mean some extra-challenges in managing and conducting research projects, but it also means a better chance of making meaningful discoveries in a country that is diverse in many ways.
Language matters, a lot.