Appendix B: Methodological Approaches and Scales

Summary

We present in this section the scale items and scales used in the reported research. We adopted the following guidelines in selecting scales. First, we relied on published scales where possible in order to use widely known measures. Second, we evaluated all scales for reliability and construct validity, dropping individual items that reduced the scale's reliability or undermined the construct validity. The items we dropped from the final scales are listed below and noted.

Third, in creating scales, missing data often pose a major problem. If a single response is omitted, the scale cannot be built and that case is treated as missing. With many scales the problem of missing data can often truncate a data set by one-fourth or even more. In order to preserve as many cases as possible, we used a mean value for all scales with the important provisos that a mean would be used if and only if the majority of items in a scale had a valid response. For example, if at least four out of six scale items had a valid response, then we used the mean score of the four, five, or six items as the scale value for that case (for seven items we required five valid responses, and so forth). If fewer than four items were valid responses (i.e., not missing) then a missing value was assigned this case.