Boyd and Gullone (1997) studied anxiety and depression in a sample of 783 adolescents attending schools in and around Melbourne, Australia. To measure anxiety, they used the Revised Children's Manifest Anxiety Scale (RCMAS). The RCMAS measures a number of different domains of anxiety (such as physiological anxiety and anxiety related to social concerns). In discussing the measure in their methods section, they note the following: "Alphab coefficient reliability estimates of internal consistency for the RCMAS range from .42 to .87". Explain these results to someone who is familiar with correlation but is unfamiliar with reliability or the statistics associated with it.