This study was conducted at one medical school for three medical student classes. While this population provided sufficient data for validation of the CHBQ, the reported results on use of CAM modalities, informational sources and CAM beliefs/attitudes are specific to these cohorts. Limitations of the study include: a different method of surveying students for CAM modality use compared to the US national telephone survey reports of the general population [2, 3], and lack of comparison with another medical school. In addition, we chose not to define each of the 14 listed CAM modalities in the survey to maintain brevity and compliance with completion, and some overlap of choices may have occurred. For example, the modality of prayer or intercessory prayer could be categorized as either "spirituality" or "meditation." However we believe that since students would have chosen only one category for each modality used, this would not have resulted in over-reporting of self-use.
One aim of this study was to validate and test the feasibility of a new measure of medical student attitudes/beliefs towards CAM use and practice. The 10-item CHBQ had similar measurement properties to the 29-item IMAQ. Responses to both measures overlapped considerably, suggesting that each measured the same underlying construct of attitudes toward the use of complementary and alternative therapies in the setting of holistic health care and alternative health belief systems. The CHBQ has the advantage of being generic to health professionals and not limited to physicians for measuring CAM attitudes/beliefs. Therefore it may be used for residency, nursing and CAM practitioner education, although separate validation studies for trainees in other disciplines remain to be done. The brevity of the CHBQ increases its practicality for repeated administrations and may facilitate greater compliance, ease of analysis, and a higher response rate, all of which contribute to the acquisition of more reliable and valid educational outcome evaluation data.
Medical students use CAM modalities at a self-reported rate higher than recently reported in the general US population [2, 3]. However, the methods of surveying the populations are different. We used a written survey in an educational setting whereas the US general population studies used telephone surveys of randomly selected households. This study revealed no differences in overall use of CAM modalities by MS 1 and MS 2 who are at different stages of their medical school training. More than 73% of students in this study reported self-use of at least one modality, compared to 42% of the US population surveyed in 1997 . The modalities most commonly used are similar to those identified by the US population: herbal medicine, massage, and megavitamins . The reasons why US patients use CAM were explored and reported in 1998 . In that study, the majority of patients seeking CAM therapies was described as being more educated, reporting poorer health, and selecting CAM therapies not because of dissatisfaction with conventional therapies, but because alternative therapies were more congruent with their values and health beliefs. In this study, the reasons why our students use CAM therapies at a higher rate than the general population were not examined.
The medical students studied are highly likely to seek information about CAM from online resources, particularly PubMed . It is difficult to account for the greater awareness of a variety online CAM resources by MS 1 compared to MS 2. This may represent a "recency effect" of a medical informatics class for MS 1 that included CAM online data sources. Since the MS 2 received the same informatics instruction in their first year, this suggests a need to reinforce the teaching of online information CAM resources in year 2 of the curriculum.
The three student class samples presented with similar characteristics, and they represented a rather homogenous group of learners. MS 2 had received three hours of required didactic CAM instruction within the Patient-Doctor course. This curriculum appeared not to have additionally impacted an already positive attitude towards CAM education and use. One shortcoming is that we did not collect information on changes in CAM knowledge and skills in the three classes studied to demonstrate an increase in these domains of learning. The finding of positive attitudes/beliefs towards CAM for all classes is useful for guiding future CAM curriculum development. Whether the positive attitudes are related to certain student demographics (such as diverse ethnicity, origin from California, or gender) specific to the 3 classes is yet to be determined. Only gender was significantly correlated with IMAQ and CHBQ total scale scores, and those correlations were small. Ethnicity was not a significant correlate. Future comparisons with medical schools having different student characteristics are anticipated and will be revealing. It is concluded that the already positive perceptions students bring at entry to medical school are maintained through a first year curriculum of predominantly basic science courses and minimal formal CAM instruction.
Future new CAM curricula will focus on knowledge and skill acquisition, such as competencies for interviewing patients for CAM use and health beliefs, and skills for searching and locating evidence on CAM modalities, rather than to change already positive CAM attitudes/beliefs. Measuring the outcomes of instruction should include and account for the effects of attitudes/beliefs on learners' acquisition of competencies. Thus, the relatively brief and easy-to-administer CHBQ will have high utility.
In summary, this study showed that students enter our medical school with positive attitudes/beliefs towards CAM practice and exhibit a high level of self-reported use of CAM modalities, above that observed in the general US population. Students have a high rate of online information-seeking behavior in relation to CAM use, but this is mostly limited to one database. The short CHBQ has the potential to measure student attitudes/beliefs. In addition, the CHBQ has potential use in other health professions education settings. Given the paucity of educational tools for measuring the impact of new CAM curricula, the CHBQ will provide a useful start to CAM attitude/belief assessment. The need remains to carefully develop and validate methods for evaluating other instructional outcomes such as CAM knowledge and skill acquisition.