Generic outcomes instruments only superficially survey pain and pain control. You might want to consider combining a recognized pain questionnaire with another outcome instrument that examines the quality of well-being. In this way, you have the potential to quantify the efficacy of your program and develop data that you can use to market your ability to treat specific pain problems. Outcomes researchers have defined methods to evaluate the validity and reliability of their questions by examining the responses of standard populations. The extent to which a question measures what it was intended to defines validity.
Reliability defines the stability of a measurement.
Using archery as a metaphor, reliability is symbolized by the scatter of the arrows, and validity is portrayed as how close you can get to the target and hit the bull's eye. An outcomes instrument should be fieldtested to determine its validity and reliability. No standard guidelines are available for validating health outcome measures, and methods derived from psychological and educational measurements have been imported. Reliability is often defined statistically by calculating Cornbach's Alpha or Pearson's r value. When shopping for your outcomes instrument, examine the questionnaire with respect to its size, conceptual basis and scoring, and consider how the patients will respond to the request for them to fill out that survey.