Exploring the Patterns of Use and the Feasibility of Using
Cellular Phones for Clinic Appointment Reminders
and Adherence Messages in an Antiretroviral Treatment
Clinic, Durban, South Africa
Tamaryn Crankshaw, M.A.,1Inge B. Corless, R.N., Ph.D., FAAN,2Janet Giddy, MBChB, MFamMed,1
Patrice K. Nicholas, DNSc, DHL (Hon), M.P.H., M.S., R.N., ANP, FAAN,2
Quentin Eichbaum, M.D., Ph.D., M.P.H., M.F.A., FCAP,3and Lisa M. Butler, Ph.D., M.P.H.4
In preparation for a proposed intervention at an antiretroviral therapy (ART) clinic in Durban, South Africa, we
explored the dynamics and patterns of cellular phone use among this population, in order to ascertain whether
clinic contact via patients’ cellular phones was a feasible and acceptable modality for appointment reminders
and adherence messages. Adults, who were more than 18 years old, ambulatory, and who presented for
treatment at the clinic between October-December 2007, were consecutively recruited until the sample size was
reached (n¼300). A structured questionnaire was administered, including questions surrounding socio-
demographics, cellular phone availability, patterns of use, and acceptability of clinic contact for the purpose of
clinic appointment reminders and adherence support. Most respondents (n¼242; 81%) reported current own-
ership of a cellular phone with 95% utilizing a prepaid airtime service. Those participants who currently owned
a cellular phone reported high cellular phone turnover due to theft or loss (n¼94, 39%) and/or damage (n¼68,
28%). More females than men switched their cell phones off during the day (p¼0.002) and were more likely to
not take calls in certain social milieus (p?0.0001). Females were more likely to share their cell phone with others
(p¼0.002) or leave it in a place where someone could access it (p¼0.005). Most respondents were willing to
have clinic contact via their cellular phones, either verbally (99%) or via text messages (96%). The use of cellular
phones for intervention purposes is feasible and should be further investigated. The findings highlight the value
of gender-based analyses in informing interventions.
promotion in a range of medical conditions. In the absence of
land lines and because of the high mobility of the population,
cellular phones are used widely throughout South Africa. The
utilization of cellular phones in the HIV/AIDS-related health
care setting has, in particular, received attention; telecom-
munication strategies in supporting health care services and
systems in resource-limited settings are on the international
public health agenda.1The effectiveness of telecommunica-
arious technological approaches have been devel-
oped to expand the health encounter and improve health
areas; supporting antiretroviral treatment (ART) adherence,2–4
facilitating HIV testing5and monitoring and follow-up of
HIV-infected patients by clinicians.6There is ongoing cellular
phone research in a range of HIV-related health care services
in South Africa7and the first multisite randomized clinical
trial in Kenya, looking at various patient outcomes including
ART adherence via a short message service (SMS) interven-
tion, is well underway.8
Sub-Saharan Africa is at the epicenter of the global HIV
epidemic. In the South Africa, 2009 national HIV prevalence
1McCord Hospital, Durban, South Africa.
2Institute of Health Professions, Massachusetts General Hospital, Boston, Massachusetts.
3Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center, El Paso, Texas.
4Department of Epidemiology and Biostatistics, Global Health Sciences, University of California San Francisco, San Francisco, California.
AIDS PATIENT CARE and STDs
Volume 24, Number 11, 2010
ª Mary Ann Liebert, Inc.
African population, has an extremely high antenatal HIV
prevalence of 38.7%.9Ethekwini (Durban) is the district in
KwaZulu-Natal with the highest prevalence of all; 40.3%.9
Despite the high national unemployment rate, use of cellular
phones is widespread among South Africans.10The South
African cellular network covers over 71% of the population,
including the remoter regions of the country. Most urban ar-
eas and national roads have full network coverage.
In preparation for an intervention to improve ART adher-
ence and clinical attendance rates at a busy urban ART clinic
in Durban, South Africa, we investigated the dynamics and
patterns of cellular phone use among this patient population
to assess whether clinic contact via patient’s cellular phones
(either verbal contact or text messaging services) was a fea-
sible and acceptable modality for clinic appointment re-
minders and adherence messages.
Setting and participants
This cross-sectional study was conducted at the McCord
Hospital antiretroviral therapy (ART) clinic, KwaZulu-Natal,
South Africa. McCord is a state-subsidized, district-level
Durban Metropolitan catchment area and has extensive ex-
perience in ART services for both adults and children. As of
The Hospital ART Clinic charged a monthly user fee of
ZAR140 (approximately $20 USD).
Adults who were 18 years of age or older, ambulatory, and
who presented for treatment at the ART clinic between Oc-
tober and December 2007 were consecutively recruited and
enrolled until the sample size of 300 was reached. All partic-
ipants were interviewed by a female research assistant who
had extensive qualitative and quantitative fieldwork experi-
ence. This research assistant was not a staff member of the
hospital and received additional training regarding the study
and the research instrument.
Participants were interviewed by the same interviewer
using a structured questionnaire and administered in English
or isiZulu, depending on respondent preference. The inter-
view included questions about sociodemographic character-
istics, cellular phone availability and patterns of use, and
opinions about the acceptability of the clinic contacting the
individual by voice or text messaging for the purpose of clinic
appointment reminders as well as adherence support.
Our primary analysis compared patterns of cellular phone
use and willingness for clinic contact via cellular phone by
gender. Odds ratios (OR) and 95% confidence intervals (CI)
for associations between gender and cellular phone avail-
ability and patterns of use were calculated by logistic re-
gression. Analyses were conducted using SAS 9.1 (SAS
Institute, Cary, NC).
Ethical approval for the study was obtained from the
study was conducted and the Institutional Review Board of
the Spaulding Rehabilitation Hospital. Respondents were
asked to provide verbal consent to indicate willingness to
Between October and December 2007 we consecutively
enrolled 300 individuals 18 years of age or older who pre-
sented for treatment at the ART clinic. There were 2 refusals.
Most respondents (n¼242; 81%) reported current ownership
of a cellular phone (median time of ownership¼3 years).
Older age (years) (adjusted odds ratio [AOR]¼1.05, 95% CI
cellular phone ownership. Gender was not associated with
cellular phone ownership (p¼0.97). The following analyses
are based on the 242 participants who reported current
ownership of a cellular phone.
Characteristics of participants who owned
a cellular phone
The majority of participants were female (67%), with me-
dian age of 35 years (interquartile range, 30–40 years), and
were black Africans (96%; Table 1). The male/female ratio as
well as ethnicity and age group was representative of the
patient profile accessing services at the ART clinic. The ma-
jority of respondents (60%) were unemployed, and approxi-
mately half had at least a secondary level education (52%). Of
all respondents, 32% reported currently receiving financial
support from government social grants (e.g., child care or
disabilitygrants);asignificantly greaterproportion offemales
reported accessing these grants than males (43% versus 10%,
p<0.0001). The sample was evenly balanced with respect
to time since HIV diagnosis and time on ART indicating a
representative selection of the patient population with regard
to these dimensions.
High cellular phone turnover due to theft,
loss and/or damage
The majority of participants (95%) utilized a prepaid air-
time service. This route to accessing airtime allows the user to
buy airtime on an ad hoc basis, allowing for financial con-
straints without being tied into a standard 2-year contract
with a set monthly fee. There was high cellular phone turn-
over due to theft, loss, and/or damage. Close to 40% of re-
spondents reported that they had previously owned one or
more cellular phones that had been lost or stolen, and 28%
had been damaged to the extent that they could not use it.
Patterns of cellular phone use
Twenty-three percent of respondents reported that they
switched their cell phones off during the day (Table 2). Fe-
males had almost four times the odds of reporting that they
switched their cell phone off during the day than males
(p¼0.002), citing attendance at church, prayer meetings,
730CRANKSHAW ET AL.
funerals, and doctor visits as typical reasons. Fifty-nine per-
busy streets, unsafe areas, funerals, church, work, schools.
Females had almost five times the odds of reporting this than
Twenty-eight percent of respondents reported that they
shared their cell phone with one or more other people (Table
2). The odds of sharing a phone were significantly greater for
females compared to males (OR¼3.0, 95% CI 1.5–6.0).
Household members were the predominant category of per-
son with whom cell phones were shared but with important
differences between males and females. Whereas men most
commonly reported sharing their cell phones with their wives
(n¼5/12, 42%), females more commonly reported sharing
their phones with their family members (n¼28/56, 50%) or
children (n¼22/56, 39%).
One third of respondents reported that they sometimes
left their cell phone in a place that allowed the potential
for someone to pick it up and access it (e.g., to use it or
read messages on it; Table 2). The practice was significantly
more common among females than males (OR¼2.4, 95% CI
One quarter (25%) of respondents who currently owned a
cellular phone believed that their text messages had at some
point been read without their permission (Table 2). However,
those who elaborated on this could identify the family
member/s concerned and did not appear to be unduly dis-
turbed by this.
Willingness for clinic to contact by cell phone
The majority (87%) of participants indicated that they
usually answered calls that displayed ‘‘private number’’
(which is how the Hospital number would be displayed) on
their caller identification screen (Table 2). Among the 31 re-
spondents who reported that they routinely did not answer
calls from unknown numbers, the main reasons offered in-
cluded concerns about sexual rivals phoning to insult them,
crime, or being contacted by a service provider requiring debt
to be paid.
Most respondents were willing for the clinic to contact
them on their cellular phones either verbally (99%) or via text
messages (96%). Of three persons (all women) who stated that
they would not be willing for the clinic to contact them ver-
bally, one expressed concern that she did not want to be
‘‘chased’’ by the clinic and two explained that they did not
need reminders because they knew their appointment dates.
Of the nine participants (three men, six women) who stated
that a text message from the clinic would be unacceptable,
concerns included their not knowing how to access the mes-
sage, not being able to read messages immediately, not being
able to read, that someone else might see the message, and
Table 1. Characteristics of Study Participants Who Currently Owned a Cellular Phone (N¼242)
Median years (IQR)
30 to 35 years
36 to 40 years
Primary or less
Receive government grantsa
Time since HIV diagnosis
0 to 6 months
7 to 2 months
Time on antiretroviral therapy
0 to 6 months
7 to 12 months
IQR, interquartile range.
PATTERNS OF CELLULAR PHONE USE IN ART CLINIC SETTING731
that a reminder was not necessary because other reminder
strategies were already used.
Use of cell phones as reminders
Use of the cell phone alarm function was a commonly
mentioned strategy for remembering to take medication on
time. Most of the participants (79%) were already utilising the
received text messages from treatment supporters.
Research focusing on the efficacy and effectiveness of in-
terventions that utilize communication technology in facili-
tating ART adherence is being strongly supported by various
international public health agencies. In resource-limited set-
tings, in particular, communication technology offers prom-
ising possibilities in addressing current HIV-related health
care services infrastructural and human resource constraints.
The purpose of this research was to understand existing pat-
terns of cell phone use in a population on ART, as well as
assess attitudes regarding the possibility of the clinic using
cell phones to communicate with clients.
Among patients attending an urban ART clinic in Durban,
South Africa, we found that the majority (81%) of patients
currently owned a cellular phone. As such, for most patients,
contact by cellular phone is a viable option. However, our
findings highlight several issues that should be considered in
the design of an intervention involving patient contact by
cellular phones. For example, the issue of loss of cell phone
devices due totheft and/or damagewas common, and would
have implications in terms of sustainability of such an inter-
vention, as well as issues of confidentiality with lost devices.
While the device itself could be relatively easily replaced, the
majority of participants used prepaid airtime which meant
that they would lose their original phone number once they
had acquired their new cell phone with another Subscriber
Identity Module(SIM)cardwhich is preallocatedthenumber.
Regular updating of patient contact details at each clinic visit
was therefore demonstrated as imperative.
We found differences in the patterns of use of cellular
phones between men and women. Women were significantly
more likely to have their cellular phones used by others in
their lives and to not be contactable either due to refusing to
answer their phone or to switching it off in certain social
settings. Text messaging would address the problem of cell
phones users not beingavailable at the time ofcontact, but the
issues around confidentiality need to be carefully considered.
Gendered patterns of cellular phone use need to be taken into
account in the design and implementation of clinical inter-
ventions that rely on cellular phone use. In particular, con-
siderations around the framing of the specifics of the clinic
message need to be carefully planned, with the input of clinic
patients and counselors.
Despite the gender differences in patterns of cellular phone
use, the majority of participants, regardless of gender, indi-
Table 2. Experience of Phone Theft, Loss or Damage, Patterns of Cellular Phone Use and Willingness
to be Contacted by HIV Clinic Among Participants (N¼242)
N (%)OR (95% CI)p Value
High cellular phone turnover due to theft, loss and/or damage
Has had a cellular phone lost or stolen in past
Cellular phone has been damaged in past such that it could not be used
Patterns of cellular phone use
Switch cellular phone off during day
There is sometimes a time or place where no calls are taken
Shares cellular phone with another person(s)
Phone is sometimes in a place where someone could pick it up and use
it or read messages on it
Believe that one or more persons has ever read SMSs without your permission
Willingness for clinic to contact by cell phone
Typically answers calls from unknown number
OR, odds ratio; CI, confidence interval; SMS, short message service.
732CRANKSHAW ET AL.
cated willingness to be contacted by the clinic, either in the
form of a phone call or via a text message. Interestingly, while
receiving a text message treatment reminder was considered
helpful to the majority of participants, it was not viewed by
recent Canadian study, on the other hand, reported that
electronic reminder devices were identified as helpful by re-
spondents.11Median adherence with a variety of reminder
tools was 95% and specifically with electronic devices was
to support persons living with HIV, 500 caregivers were re-
cruited to complete an online survey of Internet use and self-
efficacy.12The findings suggest that most respondents (72%)
used Internet websites for information and resources, thus
lending credence to the important role of Internet-type or
electronic reminder technologies in both HIV adherence and
found that self-efficacy and outcome expectancy were sig-
nificantly higherinadherentversusnonadherent subjects.For
those subjects with low self-efficacy and outcome expectancy,
adherence results differed based on thepresence orabsence of
either mental health or structural barriers. Thus, as the global
diffusion of mobile and Internet-based systems expands, the
need for further exploration of these technologies and their
ability to augment HIV-related behavioural interventions,
should be examined.13
This study has several important strengths. It included a
representative sample of ART clinic patients who were well
distributed in terms of sex ratio, time since HIV diagnosis,
and time on ART. While most participants indicated high
acceptability of an intervention such as this, disaggregating
the data by sex drew attention to the often hidden gender
such as the one proposed. This kind of analysis allows for a
more nuanced understanding of generalized assumptions
care and support.
There were somelimitationstothisstudyaswell.Becauseof
cellular phone usage over time. In addition, it is possible that
we have overestimated patient willingness to receive remind-
ers via cell phones given the possibility of courtesy bias. Spe-
cifically, since information was collected from patients in the
clinic where they received care, it is possible that participants
were reluctant to express negative opinions to an interviewer
who may be perceived to be associated with the facility from
was based on participants’ recall of aspects of their prior cel-
lular phone usage. It is possible that recall bias could result in
inaccurate information being inadvertently provided or col-
lected. Furthermore, generalizability of our results to other
populations should be made with some caution. Given the
clinic entrance fee, the study may have selected a slightly dif-
ferent sociodemographic sample of patients who may not be
representative of HIV-infected individuals with cell phones in
the study catchment area.
While the study shows that the potential value of using cell
phones to improve adherence in patients on ART, it also
highlights the need for nuanced interventions which respond
to contextual dynamics as well as gender considerations.
Given the substantial loss and sharing of cell phones, tech-
nology that requires a password to access text messages
should protect the confidentiality of the recipient with regard
to the message content. Carefully framed clinic messages
which are ambiguous enough not to generate suspicion if
accessed by an unintended recipient, but at the same time
being directed enough to be recognizable to the intended re-
cipient also need to be developed with the input of patients.
With regard to gender considerations, disaggregating the
study data by sex provides the opportunity for a gender-
based analysis. This study underlines the value of an explor-
atory feasibility study prior to interventions being im-
plemented. In addition, the role of self-efficacy and its link
with electronic reminder devices including cell phones re-
quires further study.
This study was carried out with financial support from the
Maurice Webb Trust Fund.
Ethical approval for the study was obtained from the
McCord Research Ethics Committee and the Institutional
Review Board of the Spaulding Rehabilitation Hospital.
The authors would like to thank and acknowledge Si-
bongile Maimane for conducting the interviews.
Presented in part at the 3rd International Conference on
HIV Treatment Adherence, Jersey City, New Jersey, March
Author Disclosure Statement
No competing financial interests exist.
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Address correspondence to:
P.O. Box 37587
734 CRANKSHAW ET AL.
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