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Failing to write clear and specific questions can hinder your respondents' ability to answer. The standard is that people should have a consistent understanding of what is being asked of them. If someone could interpret a question differently than you intended, the question can be improved. Avoid ambiguities.A low response rate can give rise to sampling bias if the nonresponse is unequal among the participants regarding exposure and/or outcome. Such bias is known as nonresponse bias. For many years, a survey's response rate was VIEWED as an IMPORTANT indicator of survey quality.Tips for Avoiding Non Response Bias

Design your survey carefully; use well-trained STAFF and proven techniques.

Develop a relationship with respondents. ...

Send reminders to respond.

Offer incentives to respond.

Keep surveys short.

One of the most important problems is non-response. It is the phenomenon that the required INFORMATION is not OBTAINED from the persons selected in the sample. One effect of non-response is that is reduces the sample size. ... Due to the smaller sample size, the precision of estimators will be smaller.