When conducting market research, one of the most important things to ensure is a sample size that is representative of the market you wish to target. Focus on both Confidence Level and Sampling Error. Confidence Level is the probability that the data represents the thinking of all possible participants. Sampling Error is essentially the opposite, which is the probability that there are irregularities in the data.
When you decide on the margin of error that is acceptable for your market research it is easy to calculate your ideal sample size using a sample size calculator. This will tell you how large your sample must be to ensure the market research is valid.
When developing market research questions, be careful of myopia or bias. Since market research is typically undertaken by people who are heavily invested in a product or service, they often see a very one-sided perspective of the product. In effect, they could be hindered by over-investment, neglecting to ask critical questions, or considering diverse perspectives. Furthermore, product development teams may, even unintentionally, ask a set of questions that will only confirm their existing point of view. For this reason, it is advisable to solicit an external “set of eyes” when developing your market research questionnaire.