The promise of using text messages, video or smartphone apps to improve health care has attracted a lot of attention and dollars. Yet mobile health, also known as mHealth, is still in its infancy, and a pair of new analyses shows that it has garnered mixed results. Of 75 controlled trials in which patients used mobile technology to manage a disease or adopt healthier behaviors, only three showed reliable signs of success, according to a review article published in January in PLOS Medicine.

In an accompanying review, the same authors looked at the use of mobile technology to improve health care delivery, such as using text messages to remind patients about appointments, and found that 11 of 42 trials had positive results.

Physician Rahul Chakrabarti of the University of Melbourne in Australia, co–editor in chief of the Journal of Mobile Technology in Medicine, calls the reviews the most comprehensive meta-analysis of mHealth evidence to date.

The limitations of today's mHealth treatments should not discourage researchers, says epidemiologist Caroline Free of the London School of Hygiene and Tropical Medicine, who led the analysis. People can learn from interventions that did work. For instance, receiving text messages helped smokers quit in one trial that verified its results with biochemical tests. In the only successful patient-intervention trial in the developing world, in Kenya, text message reminders to take antiretroviral drugs helped to reduce HIV virus counts.

The bad news is that most trials had weak designs, with many failing to randomize participants in the control group and the experimental group. Others relied on participants to self-report the results, even though such methods can be unreliable. Most trials also neglected the developing world, where mobile phones have the most potential to improve access to health care.

Chakrabarti, who was not involved in the research, says that the studies show “there is a clear need for improved methodology.”