Cognitive interviews guide design of a new CAM patient expectations questionnaire

Abstract

BACKGROUND:No consistent relationship exists between pre-treatment expectations and therapeutic benefit from various complementary and alternative medicine (CAM) therapies in clinical trials. However, many different expectancy measures have been used in those studies, with no validated questionnaires clearly focused on CAM and pain. We undertook cognitive interviews as part of a process to develop and validate such a questionnaire.METHODS:We reviewed questions about expectations of benefits of acupuncture, chiropractic, massage, or yoga for pain. Components of the questions - verbs, nouns, response options, terms and phrases describing back pain - were identified. Using seven different cognitive interview scripts, we conducted 39 interviews to evaluate how individuals with chronic low back pain understood these individual components in the context of expectancy questions for a therapy they had not yet received. Chosen items were those with the greatest agreement and least confusion among participants, and were closest to the meanings intended by the investigators.RESULTS:The questionnaire drafted for psychometric evaluation had 18 items covering various domains of expectancy. "Back pain" was the most consistently interpreted descriptor for this condition. The most understandable response options were 0-10 scales, a structure used throughout the questionnaire, with 0 always indicating no change, and 10 anchored with an absolute descriptor such as "complete relief". The use of words to describe midpoints was found to be confusing. The word "expect" held different and shifting meanings for participants. Thus paired items comparing "hope" and "realistically expect" were chosen to evaluate 5 different aspects of treatment expectations (back pain

back dysfunction and global effects

impact of back pain on specific areas of life

sleep, mood, and energy

coping). "Impact of back pain" on various areas of life was found to be a consistently meaningful concept, and more global than "interference".CONCLUSIONS:Cognitive interviews identified wordings with considerable agreement among both participants and investigators. Some items widely used in clinical studies had different meanings to participants than investigators, or were confusing to participants. The final 18-item questionnaire is undergoing psychometric evaluation with goals of streamlining as well as identifying best items for use when questionnaire length is constrained.