Can the ubiquitous power of mobile phones be used to improve health outcomes in developing countries?

Background The ongoing policy debate about the value of communications technology in promoting development objectives is diverse. Some view computer/web/phone communications technology as insufficient to solve development problems while others view communications technology as assisting all sections of the population. This paper looks at evidence to support or refute the idea that fixed and mobile telephones is, or could be, an effective healthcare intervention in developing countries. Methods A Web-based and library database search was undertaken including the following databases: MEDLINE, CINAHL, (nursing & allied health), Evidence Based Medicine (EBM), POPLINE, BIOSIS, and Web of Science, AIDSearch (MEDLINE AIDS/HIV Subset, AIDSTRIALS & AIDSDRUGS) databases. Results Evidence can be found to both support and refute the proposition that fixed and mobile telephones is, or could be, an effective healthcare intervention in developing countries. It is difficult to generalize because of the different outcome measurements and the small number of controlled studies. There is almost no literature on using mobile telephones as a healthcare intervention for HIV, TB, malaria, and chronic conditions in developing countries. Clinical outcomes are rarely measured. Convincing evidence regarding the overall cost-effectiveness of mobile phone " telemedicine" is still limited and good-quality studies are rare. Evidence of the cost effectiveness of such interventions to improve adherence to medicines is also quite weak. Conclusion The developed world model of personal ownership of a phone may not be appropriate to the developing world in which shared mobile telephone use is important. Sharing may be a serious drawback to use of mobile telephones as a healthcare intervention in terms of stigma and privacy, but its magnitude is unknown. One advantage, however, of telephones with respect to adherence to medicine in chronic care models is its ability to create a multi-way interaction between patient and provider(s) and thus facilitate the dynamic nature of this relationship. Regulatory reforms required for proper operation of basic and value-added telecommunications services are a priority if mobile telecommunications are to be used for healthcare initiatives.


Background
There is an ongoing, broad policy debate about the value of communications technology in promoting development objectives. The literature is diverse in its opinions. Some view computer/web/phone communications technology as merely providing a 'quick fix' for solving development problems that must be solved with comprehensive policies cutting across all sectors. Similarly, some view communications policy as increasing social gradients, in large part because of the existence of knowledge and information barriers, lack of skilled human capital and lack of funds for modernization [1]. Those who disagree about these negative positions argue that harnessing communications technology will benefit all sections of the population, will disseminate information, open opportunities for women. They point to Africa and the Arab States, in which the poor as well as the uneducated have been able to access this technology in public facilities, shared services and other innovative strategies [2,3].
Within the context of this broad policy debate on the value of information technology in developing countries, there is a specific issue that deserves attention. Are mobile telephones a potentially useful intervention to deliver healthcare, including healthcare information, in developing countries? Mobile telephone subscriptions have been growing rapidly since the 1980s in both developing and developed countries. Subscriptions to fixed telephones have also grown, but in many parts of the world growth has been at a slower rate than cellular. The demand for mobile phones exists beyond reducing the waiting list for traditional wire-line phones [1].
In 2002, mobile subscribers overtook fixed line subscribers worldwide and this occurred across geographic regions, socio-demographic criteria (gender, income, age) or economic criteria such as gross domestic product (GDP) per capita [4]. In much of sub-Saharan Africa, there are more mobile phones than fixed-line phones [5] and the use of mobile phones in many Asian countries is on the rise.
A more formal definition of a healthcare "intervention" in the present context is the following: it is an intentional activity that comes between persons or events for the specific purpose of modifying some health-related outcome or act. Thus, for the purposes of this discussion, an "intervention" has the sense of an intentional use of mobile phones to achieve a specific purpose. The functioning of the telecommunications market, by itself, is not considered an "intervention." For instance, although the mere presence of a mobile telephone in a village may enable communication with healthcare providers and lessen isolation in case of emergency, this is not considered an intervention as defined above. However, use of subsidized phones or airtime or more sophisticated applications using exiting mobile phone platforms for the express purpose of supporting or altering one or more health outcomes would be considered an "intervention". "Telemedicine" encompasses many different communication modalities and is not a single technology. It includes video and other conferencing, transmission of computed tomography (CT) images, and computer-assisted or Webbased provider-patient communication systems. Various uses of telephones have contributed to this repertoire of "telemedicine", defined as the delivery of health care and sharing of medical knowledge over a distance using telecommunications (1). In this regard, the predominant modality has been fixed telephones, in combination with enhancements such as computer-automated, telephone follow-up and counseling, telephone reminders, interactive telephone systems, after-hours telephone access, and telephone screening. See, e.g., [7][8][9][10]. There is continuing interest from academics, clinicians and policy makers about the value of these interventions to improve health outcomes and quality of life [5][6][7][8]. The term "e-health", originally used as an industry and marketing term, has also found its way into the scientific literature and may be supplanting "telemedicine" as the latest term for a very dynamic subject matter. One may briefly define "ehealth" as both a structure and as a way of thinking about the integration of health services and information using the Internet and related technologies.
Part I is a brief literature review of the uses of fixed telephones and mobile telephones as a healthcare intervention for management of a variety of diseases. What is the evidence that telephones in general, and mobile phones in particular, can be effective as a healthcare intervention in developing countries? The Discussion (Part II) summarizes the issues on both sides, that might persuade or dissuade, a potential stakeholder in a developing country from initiating healthcare interventions using mobile phones. Use of mobile telephones as a healthcare intervention in developing countries has tremendous, but as yet untapped, potential due to technical as well as financial and regulatory barriers.

Literature review
The relative lack of information for developing countries is striking. It is obvious, however, that most studies found are in wealthy nations comprising members of the Organization for Economic Cooperation and Development (OECD). Of the 3870 total participants in various fixed telephone interventions (Table 1), fully 94% (n = 3640) were in the United States. For mobile phone interventions (Table 2), of the 852 participants, 88% (n = 753) were from Europe, Japan or Korea but the reasons for this relative geographic distinction between fixed and mobile are obscure.
As this review was not intended to be exhaustive, it is difficult to generalize because of the different outcome measurements and the small number of controlled studies. The majority of reports are "pilot" or "feasibility" studies. A subset of Tables 1 and 2 is presented below as Table 3 for diabetes and hypertension-two of the conditions where there is useful information with respect to outcome measurements.
Aside from recent work in South Africa [43][44][45], there is almost no literature on using mobile telephones as a healthcare intervention for chronic, non-communicable diseases such as cardiovascular disease, diabetes, depression, and for chronic, communicable diseases such as HIV and TB. Even in developed countries, except for certain diabetes studies, clinical outcomes are rarely measured. There is almost nothing known about how such technology could be scaled up beyond the pilot stage. Moreover, the cost effectiveness of telephonic interventions is not known. A recent systematic review [46] of telemedicine (including other interventions besides telephonic ones and largely confined to developed countries) found that only a small percentage of eligible studies (7/24 (29%)) even attempted to explore the level of utilization that would be needed for telemedicine services to compare favorably with traditionally organized health care. No studies that were reviewed addressed this question in sufficient detail to adequately answer it. These authors concluded that there " ... is no good evidence that telemedicine is a cost effective means of delivering health care." [46] Evidence regarding the effectiveness or cost effectiveness of mobile telephones in particular as a telemedicine intervention is therefore still limited [46,47]. This is a weak evidence base upon which to develop policy or allocate resources.
We note that for any intervention to be "cost effective" as a means to enhance adherence to medicines, it would have to be effective in reducing the burden of illness associated with non-adherence at an optimal level of resource use. A recent review on this subject [47] was not able to make definitive conclusions about the cost-effectiveness of such interventions to enhance adherence to medicines " ... due to the heterogeneity of the studies found and incomplete reporting of results." In this recent cost-effectiveness review [47], forty-three studies were reviewed and 41 were conducted in OECD countries, the remaining two being in Malawi (malaria prophylaxis compliance [48]) and Botswana (home-based v. hospital-based TB care [49]). Difficult policy decisions are being made all the time about "rationing", i.e., the allocation of finite healthcare resources [50], and the cost-effectiveness of mobile phone technology as a healthcare intervention will become part of these decisions, if they are not already.

Discussion
Not withstanding the apparent paucity of evidence in developing countries that is more than anecdotal, certain functional and structural properties of mobile phones may make them attractive to use as a healthcare intervention.

Attractions of using mobile telephones as a healthcare intervention
Low start-up cost Living in resource-poor environments is not a barrier to use of wireless for several cultural and economic reasons. There appears to be a lower threshold of access to cell phones [51]. That is, there is evidence that the existence of a so-called "digital divide" along the socio-economic gradient is less pronounced in mobile phones than in other communication technologies such as the Internet [52]. Furthermore, mobile (i.e., wireless) costs less to rollout over large areas than does a fixed phone line and mobile networks can be built faster than fixed lines [4,5]. The social value of a mobile phone is highly valued even in resource-poor areas.
Households in developing countries may spend up to 2% of their monthly expenses on communication [5]. From an economic viewpoint, mobile phones have a shorter payback on investment compared to land lines, in large part because the scalability of mobile is greater compared to other infrastructure investments. Functionally, mobile phones are easier to use for people with lower level of [27] RCT = randomised controlled trial; CT = controlled trial  Participants were asked to reply to a minimum of 3 of the messages per day. Diary inputs were collected in a database. N = 12. Duration = 2 months SMS collection of asthma diary data is "feasible" half the participants reported more than about two thirds of the requested diary data.
[28] "The combination of SMS data collection and a traditional Web page for data display and system customization may be a better and more usable tool for patients than the use of Web-based asthma diaries which suffer from high attrition rates"  http://www.globalizationandhealth.com/content/2/1/9 skills than those needed for computers or the Internet, both of which usually require land lines.

User friendly-SMS
Pricing policies may enhance certain mobile uses, in particular use of Short Messages System (SMS) text. SMS texting is rapidly growing and is boosted in some countries such as the Philippines as a text message is less expensive than a phone call. SMS provides low bandwidth digital messaging between users and has surprised some observers by its success. Even as early as 1999-2000, the number of SMS messages in the United Kingdom grew from 159 million to 1.42 billion. In 2003, the average user in the Philippines sent 2,300 messages, making it the world's most avid texting nation. SMS is a part in almost all marketing campaigns, advocacy, and entertainment. In fact, SMS is influential enough in the Philippines that several local dotcoms like Chikka Messenger [53] and Bidshot [54] now fully utilize SMS for their services. There are a number of practical, and not very surprising, reasons for using SMS. It cost less than voice messaging and it can reach people whose phones are switched off. SMS messaging is silent which means that messages can be sent and received in places where it may not be practical to have a conversation.

Forms of payment and market potential
The standard way of paying for a mobile phone service in the United States and Europe is on the basis of a minimum use of a certain time period per month for a year. Potential customers have to provide proof of a regular income, sign a contract, and have a bank account and a permanent address. Since the vast majority of people in developing countries likely do not have any of these, mobile service providers use a prepayment system. This involves buying cards which provide phone time from five minutes to an hour. Customers can use the credit as they like over a period of weeks, and so keep control over their spending and enjoy a very cheap phone service. Prepaid cards are widely available in local stores. Once the pre-paid "outgoing call budget" has been exceeded, many persons will continue to use the mobile phone but will only receive calls. In 1998, three years after the first prepaid mobile phone scheme was launched, 40 million people were using it -about 13 per cent of the world's mobile users. In South Africa, half of all subscribers chose prepayment. In Zambia at present, all mobile phone systems use use this scheme. Prepaid telephone calling cards allow people to get money together to buy one cellular phone among them, purchase prepaid cards, and then control phone usage. RCT = randomised controlled trial; CT = controlled trial Given the sharing of mobile phones in many places and the popularity of pre-paid phone cards, evaluating the profitability of mobile telecommunications in many developing countries by considering calls made from the phone and not calls received is probably inappropriate [55,56]. Indeed, although the global average percentage of prepaid mobile subscribers out of total mobile subscribers in 2004 was about 46%, this ranged from 31% in Asia, 45% in the Americas, 62% in Europe to 87% in Africa [57].

Barriers to use of mobile telephones as a healthcare intervention Cost issues
The penetration of mobile phones in large parts of the developing world notwithstanding, mobile access is more expensive than fixed line access since one is paying for "coverage" rather than connection to a specific location [4,58]. Makers of mobile handsets make their profits selling high-end units to consumers in developed countries so profit margins may have to be much lower in emerging markets such as Africa [56]. In most countries in the developing world, it is still expensive to buy a handset and novel strategies to improve connectivity have arisen, such as the practice of sharing mobile phones in communities. Compared to the average income of its inhabitants, the cost of a one minute outgoing call on a mobile network in most non-European/U.S. countries is arguably quite expensive, ranging from $0.50 in Brazil, to $1.00 in Senegal to $1.30 in Nigeria [57]. Lack of electricity will be a problem although this can be overcome in clever ways, e.g., one person takes village's cell phones to have them all charged at once [5].

Information carrying capacity
The low bandwidth of mobile phones leads to a lack of structure and nuance in content. SMS text messages are limited to 160 characters. Although SMS messaging is silent, the restriction on structure means that it may be difficult to carry on a potentially complex real-time interaction between patient and provider. Further, costs of data transmitted over mobile phone are greater than voice costs. Extensive use of transmitting data using mobile phones in developing countries has not been demonstrated [5,55].

Language and illiteracy
Pervasive illiteracy may be the rate-limiting step on use of SMS text messaging [4] and the combination of illiteracy and indigenous languages may have dramatic effects on the use of SMS messaging. The implications of this will extend to use of text messaging to convey health information. For example, in the UK, the ratio of the number of outgoing voice calls made to the number of outgoing SMS messages sent is 0.6:1. In South Africa as a whole, the ratio was 3:1 for pre-paid phones and in the rural communities surveyed by Vodafone, the average ratio was a remarkable 13:1 [5]. In Ndebe, a rural community in South Africa, the ratio was 17:1, but when one considers this in the context of a community in which education is not universal, the data are more understandable [5]. We note that if new communication technologies are introduced slowly, then SMS text messaging will not be replaced anytime soon but illiteracy will clearly impact its use. The development of voice recognition-mobile phone applications would also be useful in countries with high levels of illiteracy but this is a third generation (3G) application and does not seem likely to impact many resource-poor countries in the near future. Nonetheless, illiteracy does not have to be an insurmountable barrier. The CyberTracker project [59] allows mostly non-literate San people of the Kalahari in Southern Africa to transfer their knowledge about migratory movements of wild animals by giving them handheld portable computers with a touch-sensitive screen. In conjunction with signs and symbols and an attached GPS, field data is rapidly collected. Such modalities are possible using mobile phones enabling Java technology.
The mobile phone (e.g., wireless) industry has done very well selling low bandwidth "pipes" for connectivity, and it appears determined to increase the content available on mobile phones [60]. The 3G systems will provide considerably higher bandwidth than current phones, and will include images, Internet access, and videos. This bandwidth is universally touted as a way to provide Internet access, and in particular to sell content to users. SMS messages can leave a record, whereas a telephone conversation will not. The ability to extract old SMS text may be important for privacy of healthcare information for TB or HIV-infected persons where the threat of being stigmatized is present.

There is not enough evidence to support or refute the claim that mobile phones "work" as a healthcare intervention
With regard to Tables 1 and 2, perhaps we should not be surprised that the effects of telephone interventions on various clinical and other outcomes are mixed. To conclude that such interventions probably work some of the time is a trivial response. More significantly, and particularly with respect to improving medication adherence in important chronic non-communicable conditions that are increasingly prevalent in less developed countries (hypertension, diabetes, depression), any realistic intervention to improve adherence must be both dynamic and sustainable over time as patients' lives and circumstances will change. Adherence interventions must be temporally flexible and creative to track changes in the patients' relationship to the healthcare system. Indeed, such interven-tions as summarized in Tables 1 and 2 might in principle be effective most of the time provided we can understand how to give the appropriate message in a way that becomes an integral part of the recipients' life. This is clearly true whether or not phones are used as the intervention. This long-term contextual view of adherence to medicines is particularly germane to the chronic conditions mentioned previously. A health-related message must be understood consistently over time and be culturally and socially appropriate to the indication and to the real-time needs of the patient. This is a daunting challenge for whatever medium is used. A recent review [61] of the varied health-related uses of SMS applications suggests that it " deliver [s] both efficiency savings and improvements in the health of individuals and public health." However, many of these uses have not yet been subjected to clinical trials and none have been systematically extended on a large scale. The overall lack of well designed, randomized clinical trials with economic evaluation to confirm or refute clinical and economic benefits with mobile phone/healthcare interventions is an evidence gap that should be addressed in a systematic way.
The physical components of a telephone, i.e., the handset or headset and the network, are not isolated but are part of an entire system that includes pricing plans and other incentives which can provide leverage employed by healthcare professionals and policymakers. Notwithstanding any impact on health outcomes by the message itself, the effect of mobile phones, the particular payment plan and related components. i.e., the medium itself, on delivery of the "intervention" is not well understood either. Indeed, the medium that delivers an intervention may have a neutral, positive, or even negative impact on the health intervention it is delivering. This aspect of the debate about use of telecommunications as a healthcare intervention has hardly been addressed at all, in any environment.

A developed world model of mobile phones may not be appropriate in developing countries
Inter-country comparisons of aggregate statistics for 73 countries derived from the International Telecommunications Union [62] are shown in Figure 1, below and in additional File 1: Spreadsheet.xls of summary statistics of GDP per capita and mobile subscriptions per capita for various countries.
In Figure 1, the relationship between GDP/capita and mobile phone subscriptions per capita suggests that small changes in "wealth" will result in large changes in mobile phone penetration in poorer countries at GDP/capita less than about $3-4,000. Whether or not this inference really holds for resource-poor countries that lie at the lower end of this graph is an open question. The non-linear nature of Figure 1 also suggests that income has less of an effect on mobile phone penetration per capita in the more affluent countries. It is worth noting that the nature of Figure  1 is similar to the relationship between "wealth" and health indicators such as life expectancy. The ramifications of this latter relationship are still subject to continuing debate. It is possible that the health of individuals in a society also depends on the degree of income inequality in that society and that the effect of distribution of income on health, and possibly on many other things including mobile phone penetration, is more important than absolute income. Aggregate-level analyses of "developed" and "developing" countries will not illuminate issues about determinants of individual health, or mobile-phone use as related to health. The question as to whether computer/ web/phone communications technology can solve development/health problems should be shifted from a discussion about 'developing vs. developed" countries to whether use of telecommunications, and mobile telephones in particular, in healthcare is appropriate to the specific national and local context.
In Africa, mobile penetration rates are low by developed country standards but use of pre-paid calling cards and the informal sharing of mobile phones between people all increase accessibility, even in rural communities. The impact of mobile extends well beyond what might be suggested by measuring the aggregate number of subscriptions. Shared use in some locations could be an important constraint if mobile phones are to be used to convey health information since two-way communication in a shared system is difficult as a non-owning user can make outgoing calls but cannot receive spontaneous calls [4]. SMS text messages, if not deleted, can be observed by subsequent users. These informal arrangements that extend the reach of telecommunications beyond the individual user seem very powerful. Policy debates on information technology policy generally and health policy in particular are not sufficiently informed by evidence of this type [5].

Creating a sustainable, large-scale mobile phone/ healthcare model requires agreement among different stakeholders with different agendas
The work summarized in Tables 1 and 2 are almost invariably small, academic pilot or feasibility studies. A major unresolved issue when approached from the point of view of "who is doing the intervention" relates to whether these studies can be scaled-up in the community and whether they can have an impact on individual and, ultimately, on public health. Table 4 summarizes the different perspectives of some of the major stakeholders who might be expected to use mobile phone technology in a large-scale health intervention.
Patients are looking at an intervention using telecommunications broadly, and mobile telephones in particular, to eliminate or at least ameliorate suffering and reduce their financial burden during the illness and healing process.
With respect to aspects of healthcare counselling, some patients may prefer face-to-face contact rather than phone or text message contact. For some persons, communication of almost any type using SMS messages will lack nuance and individual "tailoring" so that synchronous, real-time voice communication between patient and healthcare provider will be preferred. Real-time communication can clearly be realized using mobile phone technology. A consideration with respect to asynchronous communication, i.e., with a time lag between sending and receiving, is that such communication may have to be secured or otherwise encrypted, especially with shared and/or stolen mobile phones.
From the viewpoint of a patient with TB or HIV or epilepsy, the ease of use of mobile devices could be a potential problem since, unless encrypted in some way, an email/text message opened because of a theft or viewed inadvertently will increase the risk of being stigmatized. It is not clear if this issue is important in actual practice. "Privacy" can be seen as an aspect of security -one in which trade-offs between the interests of one group and another can become particularly clear [63]. Security services (e.g. that based on digital signatures) probably do not come without transaction costs to the end-user as well as society since supportive law would need to be implemented in many countries. Nonetheless, in mobile infrastructure in developing countries, privacy/security and authentication services can be based on certificates and secret keys implemented in SIM (Subscriber Identity Module) cards. Here the patients and healthcare professionals may sign and prove digitally, and if needed, encrypt all their communications. This is a subject well beyond the scope of this paper but see, for example [64].
Healthcare providers are also looking for treatment that will eliminate or at least ameliorate suffering and improve communication of health-related issues between themselves and patients. Providers in managed care settings utilizing telecommunication/mobile structure as an intervention nonetheless might share the same concern, albeit based in easing their own financial burden and improving their bottom line. From this viewpoint, voice counselling may be time and money-intensive so providers may actually prefer automated interactions. Although a provider's first priority might be to proactively transmit information via mobile phone to the patient (i.e., "We notice that your blood sugar has gotten low... do this..."), the ability of this to make a clinical difference will be a function of whether the patient can understand the information and act upon it. This is therefore a function of the mobile phone context, i.e., its intrusiveness, timing, quality, clarity.
It is worth noting that with respect to using mobile phones to monitor diagnostic indices, any chemical, biological or physical marker must be easily determined and easily sent via the mobile phone.  load count. Weight loss and known side effects are more likely markers for "wireless" monitoring of HIV status. The great potential advantage of mobile phone technology in managing chronic conditions is that it can collect small amounts of data rapidly, efficiently and with minimum intrusion. A healthcare intervention that requires communication of relatively simple information (e.g. weight or a spirometry result or a blood glucose value) may be preferable to content that demands more sophisticated modalities like video. Even with the relatively simple interventions under review here, the mobile phone company must be aware of possibly unique legal issues relating to security, privacy authentication, theft of identity, liability for harm due to unauthorized/negligent transmission of health information and the like [64].
From a business point of view, mobile telephone companies make their profit in the private sector. They are only likely to invest in such technology in the public research sector for reasons of -for want of a better term-"corporate responsibility". Clearly, however, the more realistic priority in scaling-up mobile phone infrastructure to support a phone-based healthcare intervention will be to keep their existing clients and attract new ones. Monitoring the cost of the content (the message) as opposed to mere connectivity (the medium) is important. An additional consideration is their attempt to manage their way through a changing regulatory environment, especially with stateowned telecom networks [52,65,66]. Creating a sustainable business model among the stakeholders, as well as insurers and pharmacists will be needed and is a challenge A supportive legal, governmental and business infrastructure for such a model is no less a challenge in a developed country.
New modalities such as broadband access technologies (e.g. WiMAX, Flash-OFDM, VoIP and so on) are being created all the time. Within these infrastructures, not only data (e.g. web, e-mail), but also voice over internet (VoIP) services will be widely possible in many places. With these new wireless access technologies, transmission speeds of 500-1000 kilobit/s, even higher, are possible. When framed in the present context, the question of whether or not these are suitable modalities for improving health outcomes, must be informed by the particular social and behavioral health context at several levels, i.e., countrylevel down to patient-level.
The larger debate about communications technology as a barrier or spur to development may not be resolved for some time. The communications and services infrastructure to support large-scale use of telecommunications as a health intervention exist in some parts of Africa and in much of Asia. At present, one would hope that healthcare applications such as accessing medical self care, receiving medication adherence reminders (e.g., all the applications used in developed countries), facilitating case management of chronic conditions (e.g., diabetes, TB) are more suitable for the majority of the poor in developing countries [55,56,61,67], than receiving mortgage information or buying concert tickets.
Notwithstanding the fact that large-scale supportive infrastructure exists, a top priority goal for all governments should be to (re)-align the regulatory and pricing policy of the telecommunications sector with health policy goals. Use of various information technologies (including mobile telephones) to less developed countries and communities has been ongoing for some time, mostly via the many specific initiatives, led by communities, development, donor and business organizations. Evidence on the effectiveness of these initiatives with particular regard to their use as healthcare interventions is mostly in the form of anecdotal material. More rigorous evidence is needed for drawing conclusions.
❍ The developed world model of personal ownership of a phone may not be appropriate, and may even be irrelevant, to the developing world where telephones are often shared.
❍ Convincing evidence regarding the cost-effectiveness of mobile phones as a " telemedicine" intervention is limited and good-quality studies are rare in less developed countries.
❍ Evidence of the cost effectiveness of fixed or mobile telephones as such an intervention to improve adherence to medicines was difficult to identify. Given the rapid expansion of chronic disease management (TB, HIV, non-communicable chronic conditions) in less developed countries, the ability of mobile telephone interventions to improve long-term adherence to medicines in chronic disease is unknown but could be of major benefit. Such interventions must be part of a repertoire of interventions to be used in a changing way over the lifetime of a patient. One advantage of telephones to manage chronic disease is its ability to create a two-way interaction between patient and provider(s) and thus facilitate the dynamic nature of the relationship and accompanying interventions.
❍ A framework for debate among telecommunications, development and public heath experts about the use and value of mobile phones as health intervention in developing countries will have to account for the different primary perspectives of the relevant stakeholders, the value-added of each stakeholder in a sustainable business model, as well as the context-specific nature of information technology systems in general. For a mobile telephone system to