Evaluating the reliability and validity of three tools to assess the quality of health information on the Internet.

The quality of Internet information needs to be evaluated and several tools exist for this purpose. However, none have demonstrated reliability and validity. This study tested the internal consistency and validity of the information quality tool (IQT), quality scale (QS) and DISCERN using 89 web sites discussing smoking cessation. The inter-rater reliability of the tools was established by exploring the agreement between two independent raters for 22 (25%) of the sites. The IQT and DISCERN possessed satisfactory internal consistency (as measured by Cronbach's alpha). The IQT, QS and DISCERN showed satisfactory inter-rater reliability (as measured by kappa and intraclass correlations). The IQT, QS and DISCERN correlated positively with each other, supporting the convergent validity of the tools. This study provides some evidence for the reliability and validity of the IQT, QS and DISCERN, although this needs testing in further research with different types of Internet information and larger sample sizes.