Trace elements supplementation in radiation oncology;;an empirical study assessing the quality of health information for consumers on the World Wide Web in Germany

摘要

Objective: The supplementation of trace elements as one method of complementary/alternative medicine (CAM) is becoming more important in the radioonco-logy. Actually, the internet is one of the main sources of information for CAM users but little is known regarding the quality of this kind of offered health information. Material and methods: To evaluate the quality of health information on the World Wide Web about the supplementation of trace elements in radio-oncology, we performed an analysis of consumer websites in German for this topic after screening of all citations listed in the search engines "Fireball", "AltaVista", "Google", "Yahoo", and "Lycos". Two reviewers, both experienced radiooncologists, independently analyzed this health information using the quality criteria and the scoring system of the Health Summit Working Group. Results: We found at maximum 522 web sites according to this topic, if the combination "trace element" and "cancer" and "radiotherapy" was used for search. The majority of the obtained web information was comprehensible and partly detailed, but frequently irrelevant. Only 4.4% of the analyzed web sites contained relevant statements concerning the supplementation of trace elements corresponding to scores 1 and 2 of the Health Summit Working Group scale. The observed inter-rater discrepancy was 4.3%. Conclusions: The majority of the information about the supplementation of trace elements in radiooncology, which can be found in the World Wide Web, was only of a poor quality. Therefore, qualified websites are needed to ensure an objective point of view for cancer patients with regard to the use of standard and experimental therapies of CAM for each tumor entity.