rated in some fashion into the process of communicating insights from the evaluation process.

Measurement Characteristics

Most evaluations are a combination of qualitative and quantitative approaches, each of which brings strengths and weaknesses. Qualitative studies provide greater depth of understanding about a small number of cases or subjects, often identify new variables for study or new relationships among variables, but that understanding may not generalize beyond the few cases studied. Quantitative measures typically provide greater breadth of understanding and, depending on the research design, may allow for strong inferences about causation, but the depth of knowledge will be limited (Cronbach, 1982; Francisco et al., 2001). Both approaches must deal with the issues of reliability (Will the measures yield the same result in the hands of different evaluators?) and validity (Do the measures provide an accurate picture of reality, or make accurate predictions about future events?). The former can generally be assessed by comparing measurements of a small sample of cases by two or more evaluators, and this should be possible for any MMRS evaluation tools as well. Validity testing on the other hand relies on comparison of a condition or event predicted by the measurement instrument to an actual condition or event. In the case of MMRS preparedness, the actual event would be an effective response to a large-scale CBR terrorism incident, so validation of any preparedness measurement would depend on the occurrence of a large number of such incidents. In practice, the most important measurement characteristic may be response cost, the money, time, and energy required of the organizations being evaluated, for without the enthusiasm, or at least the willing cooperation of those organizations the evaluation is liable to be meaningless.



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