Promoting uptake of HIV testing is recognized as a key priority in global HIV programming. In many countries, HIV prevention efforts are hindered by high levels of undiagnosed individuals and high levels of individuals diagnosed ‘late’ (defined as having a CD4 count of less than 350 cells per mm3 within 3 months of diagnosis and associated with significantly heightened levels of HIV-related morbidity and mortality) [1, 2]. The WHO and UNAIDS have endorsed a new global goal for 2020, specifically for 90 % of those with HIV to be diagnosed, 90 % of those diagnosed to receive ART and 90 % of those on ART to have a suppressed viral load. In order to achieve the first 90 % target around diagnosis, they have called for an expansion of existing HIV testing strategies, but also for the development and evaluation of new approaches, particularly community based approaches [3].

In the UK, as in much of Europe, African migrant communities are a priority population for HIV prevention efforts [4, 5]. Latest statistics estimate that 4.1 % of heterosexual black African men and 7.1 % of heterosexual black African women in the UK are HIV positive [5]. Of these, 38 % of men and 31 % of women are unaware of their diagnosis, and this figure is estimated to be even higher outside London (50 % of men and 41 % of women) [5]. These figures account for continuing high rates of late diagnosis within African communities. For example, in 2012 in the UK, 61 % of African women and 66 % of African men with HIV were diagnosed late [6]. A recent survey has estimated the annual HIV testing rate amongst African migrants in the UK to be 36.8 % [7]; however this number rises to 97 % amongst pregnant women attending ante-natal clinics [5].

The UK Health Protection Agency (HPA) recently conducted a series of pilot projects to evaluate the feasibility of HIV testing in ‘non-traditional’ settings [8]. These showed that the highest positivity rates were reported in the community based projects, leading the HPA to conclude that “community based pilots, targeting most at risk populations, were shown to be highly acceptable and resulted in high numbers of individuals being newly diagnosed with HIV infection and transferred into care. Community HIV testing services need to be appropriately targeted and established with strong community representation” [8:1]. They suggested that more evidence was required regarding the most effective combination of strategies that community organizations should adopt to encourage testing.

One potential strategy for enhancing the effectiveness of community based HIV testing programmes may lie in the use of new technologies, such as mobile phones [9]. In practical terms, mHealth interventions can be inexpensive and wide-reaching in application, and have demonstrated potential for reaching large samples and accessing hard-to-reach groups [1015]. Much of the existing evidence on mHealth and HIV has examined the role of short message service (SMS) interventions in supporting HIV care once a diagnosis has been made (rather than to promote testing), for example, providing appointment reminders [16, 17], enhancing treatment adherence [1822] and promoting retention in care [2326]. Overall, there are strong indications that SMS/text messaging interventions can be effective [27], but the evidence remains somewhat mixed, with some studies reporting significant increases in adherence [18, 20, 28] and others reporting no benefit [2931]. There is still much to be learned about the structure, content, tone and frequency of messages and the mechanisms by which they influence outcomes [19, 32, 33].

The evidence base for mHealth HIV prevention research remains limited but is yielding exciting results [11, 15, 3436]. Several pilot and demonstration projects have utilized text messaging interventions for HIV-related health promotion, predominantly combining information-giving with promotion of HIV testing [3739]. Outcomes relating to knowledge, changes in risk assessment and testing behavior have usually been measured through proxy indicators (such as calls to help-lines or changes in uptake of HIV testing in local clinics) [40]. However, two recent small scale randomized controlled trials in Kenya [35] and South Africa [36] have suggested that SMS interventions may have a direct impact on encouraging HIV testing behaviors.

To date, most research on SMS-based HIV prevention has been conducted in low and middle income countries [11, 15], with only a few studies reported from higher income contexts, primarily the USA [22, 39, 41]. Despite promising initiatives in other settings and with other populations, the efficacy of this approach amongst African migrant communities living in high-income countries has yet to be demonstrated. Furthermore, there is limited evidence documenting the message and intervention development process underpinning HIV-related mHealth interventions [4246]. Indeed, lack of process-related evidence has been a common criticism of m-health interventions in general, threatening intervention transferability and hindering the development of more theoretically informed understandings of implementation processes.

Evidence on effective community-based programs suggests that the social marketing approach has been most effective in achieving positive outcomes, as well as recruitment and community engagement [47, 48]. Community-based social marketing requires that before the efficacy of an intervention can be established, development and feasibility work is required to ensure that the intervention meets the needs and expectations of users, and to ensure that the procedures associated with the intervention delivery and research processes (e.g. health or behavioral outcomes, methods of data collection) are appropriate [49, 50].

This paper describes the research and development processes used to identify the key HIV-related issues reported by African migrants in the UK and to inform the development of an SMS intervention entitled ‘Health4U’. First, it reports the research that was collaboratively undertaken to explore views within Nottingham’s African communities on HIV and HIV testing, on the proposed mHealth intervention and on appropriate message content, structure, language and frequency. Second, it demonstrates how these insights were used to collaboratively design and pilot a culturally appropriate, locally relevant and theory-informed SMS intervention. Quantitative outcomes are reported elsewhere [51].