Information by Design
Lifestyle Survey Toolkit

Trade-off Between Data Collection Methods, Bias and Costs

Survey Method High Cost Response Rate Bias
Face-to-face Interview Survey   Can be high with call-backs. Needs pre-information and publicity to improve involvement. Contact rate can then be c70% Can be Low
Telephone Survey   Can be high, using call-backs and pre-information helps contact rate. Selection bias likely to be high (given reducing use of land-lines, TPS etc. Some response bias likely
Postal Survey   Response rates seem to be declining (40% is a good rate at present) Response bias can be high. Certain groups less likely to respond.
Online survey   Response is usually fairly low (less than half of postal). Incentives can increase response. Usually high from selection bias and response bias.
  Low Cost