Bone health is a significant public health issue in the United States. An estimated 10 million Americans age 50 and older are living with osteoporosis, and approximately 50% of women and 25% of men over age 50 will experience an osteoporosis-related fracture in their remaining lifetime. Recent research advancements have produced effective measures to improve and maintain bone health, including exercise, diet, screening tests, pharmacotherapies, and fall prevention strategies. These findings, however, have not been fully incorporated into the daily lives of adults, and many are unaware of the magnitude of bone-health problems. Thus, greater efforts must be made to effectively disseminate evidence-based research findings to improve bone health behaviors of the public. The Internet, with its increasing popularity, can be an effective tool in this endeavor. Despite a great deal of available online health resources, there has been a lack of research investigating effective methods to package and deliver these resources to yield positive public health outcomes. Expanding upon our prior findings and using an innovative approach combining two models of the social cognitive theory (SCT) and the RE-AIM framework (Reach, Effectiveness, Adoption, Implementation, Maintenance), in this proposal, we propose a large scale online study (N = 866) that will compare the long-term impact of two SCT-based online bone health interventions in adults age 50 and older targeting two large online communities. The two interventions are (1) an 8-week SCT-based Online Bone Health (TO-BoneHealth) program and (2) a 12-month TO-BoneHealth Plus program, including the TO-BoneHealth program followed by biweekly theory-based eNewsletters with follow-up of each individual's bone health behaviors ("booster" intervention) for 10 months. The interventions' impact will be assessed on the following the modified RE-AIM framework: (a) Effectiveness (knowledge, selected bone health behaviors, fall incidence, initiation of a discussion about bone health with a primary care provider, eHealth literacy); (b) Reach (number of participants the program reached); (c) Implementation (program usage); and (d) Maintenance (participants' bone health behavior maintenance). With the rapid growth of online communities, findings from this study will significantly contribute to current eHealth practice and research and serve as a dissemination model for other health promotion projects targeting online communities.
