A critical aspect of respondent cooperation is the actual degree to which people participate in research. But, what is the best way to tangibly measure participation?

Respondent participation can be measured on individual surveys through mathematical formulas that indicate (among other things) the percentage of respondents who completed a given survey, the percentage who refused to complete a survey, and how to determine those who were selected for a survey but were actually ineligible for participation.

A number of scholars and survey research professionals have done extensive work in this area in order to standardize these formulas. The resulting standardized formulas allow one survey to be compared to another in terms of their level of survey non-response.  MRA recommends the following resources:

Probability Surveys
AAPOR's Standard Outcome Rate Definitions – A guide to coding & calculating response rates. These include surveys that utilize randomly selected respondents from a known universe.

Non-probability Surveys 
ACE Approved Metrics - Traditional outcome (and response rate) calculations do not apply to surveys that utilize non-probability respondent selection (e.g. opt-in Internet panels, etc.).  The Association Collaborative Effort (ACE), which includes MRA, has developed outcome rates for non-probability surveys.