Mobile health evaluation methods: the Text4baby case study.

Mobile phones have been shown effective in several public health domains. However, there are few evaluations of the effectiveness of mobile health in health promotion. Also, although many studies have referenced behavioral theory, none appears to have explicitly tested theoretical assumptions or demonstrated mechanisms of change. More robust evaluation models that incorporate theory and measurement of behavioral mediators are needed. As in all public health programs, mobile health operates within a social ecological context. For example, organizational- and individual-level programs seek to influence health and health care practices and individual health behaviors. New programs such as Text4baby demonstrate how theory and explicit testing of mediators can be incorporated in evaluations. There are challenges and opportunities facing mHealth evaluations given the nature of the mobile channel. Mobile communication is ubiquitous, available at all times and places, and thus experimental control is often difficult. Natural experiments using variation in dosage of mHealth and place- or location-based designs may increase experimental control. Text4baby is a text messaging program that provides prenatal care messages to pregnant women and new mothers. It uses a partnership model with health care facilities often serving as local implementation partners. The authors review a case example of the evaluation of Text4baby at Madigan Army Medical Center. Participants were randomized to usual prenatal care plus text messaging or usual care alone. The evaluation has a theoretical model of behavior change and measures mediators as well as behavioral outcomes. Results will inform how behavioral theory works within mobile health programs.