Validity and reliability of the interval scale of anxiety response.

The Interval Scale of Anxiety Response (ISAR) is shown to be a valid and reliable instrument for measuring situation dental anxiety in adults. The ISAR demonstrates differences that are known or expected between various population subgroups. Thus, significantly higher scores, indicating greater levels of anxiety, are reported by women compared with men; by hospital clinic patients compared with private practice patients; by occasional compared with regular users of dental care; by those with lower educational levels; and by those patients undergoing exodontia compared with patients having other dental procedures. Younger adults also report significantly higher anxiety scores during treatment than older adults. The ISAR is also significantly associated with other measures of anxiety and pain, and with a measure of dentistrated difficulty of extraction. Reliability is assessed favorably and present-time administration is found to improve ISAR accuracy over its retrospective use.