5. We have made a rating that indicates how widely the method has been used because, other things being equal, it will be advantageous to select a commonly used measurement technique. The rating refers to the number of separate studies in which the method has been used rather than to the number of publications that describe the method, because one study may give rise to a large number of reports. Three categories indicate how widely the scale has been used: a few(one to four) published studies have used the method, several(five to twelve) studies by different groups, or many studies(more than a dozen studies). 6. Four ratings summarize evidence of reliability and validity. The first and third summarize the thoroughness of reliability and validity testing: 0 No reported evidence of reliability or validity Basic information only, information only by the original authors of the scale Several types of test, and several studies by different authors have reported reliability or validity All major forms of reliability or