Obviously the answer to the first question is the person who designed the study, the readership of the report and experts in the field. The second question is extremely important. On what basis do you (as a researcher), a reader as a consumer or an expert make this judgement? In the social sciences there appear to be two approaches to establishing the validity of a research instrument. These approaches are based upon either logic that underpins the construction of the research tool or statistical evidence that is gathered using information generated through the use of the instrument. Establishing validity through logic implies justification of each question in relation to the objectives of the study, whereas the statistical procedures provide hard evidence by way of calculating the coefficient of correlations between the questions and the outcome variables. Establishing a logical link between the questions and the objectives is both simple and difficult. It is simple in the sense that you may find it easy to see a link for yourself, and difficult because your justification may lack the backing of experts and the statistical evidence to convince others. Establishing a logical link between questions and objectives is easier when the questions relate to tangible matters.