Personalised electronic messages to improve sun protection in young adults

We studied the acceptability and feasibility of delivering sun protection messages via electronic media such as short message services (SMS) to people aged 18-40 years. An online survey was conducted using a pre-established panel of volunteers. We compared the characteristics of those who indicated that they would like to be alerted to the UV index, with those who would not, using bivariate logistic regression. Characteristics found to be associated with a desire to receive such advice were entered into a multivariate logistic regression analysis. The median age of the 141 participants was 34 years. Overall, 80% of participants agreed that they would like to receive some form of sun protection advice. Of these, 20% preferred to receive it via SMS and 42% via email. Willingness to receive electronic messages about the UV index was associated with being unsure about whether a suntanned person would look healthy and greater use of sun protection in the past. Careful attention to message framing and timing of message delivery, and focus on the short-term effects of sun exposure such as sunburn and skin ageing should increase the acceptability of such messages to young people. Sun protection messages delivered to young adults via electronic media appear to be feasible and acceptable.     

High mobile phone ownership but low internet access and use among young adults attending an urban HIV clinic in Uganda

Whilst there is increasing interest in the use of mobile phones and other technologies for improving health outcomes (mHealth), limited data exists on how young people living with HIV use these technologies to gather information and support their health. We sought to assess access and use of mobile phones and the internet among young adults living with HIV attending the Infectious Diseases Institute (IDI) clinic, Kampala. Data collection took place between March 2014 and January 2016 among young adults aged 18–24 years attending the IDI transition clinic in a cross-sectional survey using a semi-structured questionnaire. Of the 272 young adults interviewed, 75% were female and median age was 22.3 years (IQR: 20.6–23.5). Whilst there was a trend to females being more likely to use mobile phones compared to the males, this was not statistically significant (93.7% female versus 85.9%, p = 0.057). Fifty percent of mobile phone users used their phones for HIV-related activities such as medication reminders. General access and use of the internet was low at 34% and users were more likely to be males than females (45.5% versus 30.6%, p = 0.027). A third (32.3%) of the internet users used it to search for HIV-related information. Owning a mobile phone was associated with ease of access to HIV information and preference to receive messages via text messages (p < 0.05). Having internet access was associated with very easy access to HIV information and preference to receive information via email. Despite the rise in smartphones and internet access in Uganda, in this group both access to and use of standard mobile phones are higher than internet-based methods such as email. Using newer technologies to engage with patients especially young people is a great opportunity, but the innovations need to be tailored to the needs and technology access for different patient populations.     

Effectiveness of email-based reminders to increase vaccine uptake: a systematic review

BackgroundIn times of vaccine hesitancy and decreasing immunization coverage, it is crucial to exploit the potential of digital solutions to support immunization programmes and ultimately increase vaccine uptake. Scant evidence exists on the impact of email-based immunization reminders. In particular, while email communication is exponentially increasing at the global level, its use for health communication is still sporadic and limited data exists on its application to immunization programmes. The objective of this study is to systematically retrieve and critically appraise the available literature on the effectiveness of email-based reminders to increase vaccine uptake, with the ultimate aim to inform and encourage its integration in the implementation of immunization programmes.MethodsWe conducted a systematic review of literature following the PRISMA. We included studies providing quantitative comparative data on any measure of vaccine uptake. We extracted data on study design, study population, vaccine type and details of email-based interventions; data were pooled by type of comparison (no reminders, traditional reminders, other digital reminders).ResultsEleven studies were included, 90% with experimental study designs. While email communication succeeds in increasing vaccine uptake when compared with no intervention, weak and heterogeneous data exist supporting the superiority of email reminders, as compared to traditional methods or other digital reminders. Encouraging evidence report the effectiveness of reminder methods combining different strategies and tailored to target populations’ preferences.ConclusionsTheoretically, email communication offers many advantages: it is cheaper and faster, it can be automated and linked to electronic immunization registries, and reach people on the move. As we urge the need for further research to prove email communication impact on vaccine uptake in different settings, we underline the importance of identifying how to best integrate email communication in vaccine delivery equipping immunization programmes with technical infrastructures and normative frameworks suitable to embrace innovation.     

How Effective Are Short Message Service Reminders at Increasing Clinic Attendance? A Meta-Analysis and Systematic Review

Background and Objectives

In the last few years there has been a steady uptake of mobile phone short message service (SMS) reminders to increase medical attendance rates. We undertook a review of studies that assessed the effectiveness of SMS reminders at increasing the uptake of appointments in health care settings.

Methods

We reviewed studies which involved a comparison of appointment attendance rates between patients who did and did not receive SMS reminders published prior to June 2010. We used meta-analysis methods to calculate the overall effect on attendance rates, stratified by study design and clinic type.

Results

The review criteria were met by 18 reports, made up of eight randomized controlled trials (RCTs) and 10 controlled observational studies. Across all studies, there was significant heterogeneity in the estimated effect measure of the relationship between use of SMS reminders and clinic attendance (I² = 90 percent; p < .01), so a summary effect estimate was not calculated. Stratification by study design showed that the heterogeneity was due to the observational studies. The summary effect from the RCTs was 1.48 (95% CI: 1.23–1.72) with no significant subgroup differences by clinic type (primary care clinics, hospital outpatient clinics), message timing (24, 48, and 72+ hours before the scheduled appointment), and target age group (pediatric, older).

Conclusions

Short message service reminders in health care settings substantially increase the likelihood of attending clinic appointments. SMS reminders appear to be a simple and efficient option for health services to use to improve service delivery, as well as resulting in health benefits for the patients who receive the reminders.     

SMS text message reminders to improve infant vaccination coverage in Guatemala: A pilot randomized controlled trial

BackgroundPatient reminder systems are an evidence-based way to improve childhood vaccination rates but are difficult to implement in low- and middle-income countries (LMICs). Short Message Service (SMS) texts may offer a potential low-cost solution, especially in LMICs where mobile phones are becoming more ubiquitous.ObjectiveTo determine if an SMS-based vaccination reminder system aimed at improving completion of the infant primary immunization series is feasible and acceptable in Guatemala.MethodsA pilot randomized controlled trial was conducted at two public health clinics in Guatemala City. Infants aged 8–14 weeks presenting for the first dose of the primary immunization series were enrolled in March–April 2013. Participants randomized into the intervention received three SMS reminders one week before the second and third dose. A follow-up acceptability survey was administered to both groups.ResultsThe participation rate was 86.8% (321/370); 8 did not own a cell phone and 12 could not use SMS. 96.9% of intervention parents were sent at least one SMS reminder prior to visit 2 and 96.3% prior to visit 3. Both intervention and usual care participants had high rates of vaccine and visit completion, with a non-statistically significant higher percentage of children in the intervention completing both visit 2 (95.0% vs. 90.1%, p = .12) and visit 3 (84.4% vs. 80.7%, p = .69). More intervention vs. usual care parents agreed that SMS reminders would be helpful for remembering appointments (p < .0001), agreed to being interested in receiving future SMS reminders (p < .0001), and said that they would be willing to pay for future SMS reminders (p = .01).ConclusionThis proof of concept evaluation showed that a new application of SMS technology is feasible to implement in a LMIC with high user satisfaction. Larger studies with modifications in the SMS system are needed to determine effectiveness (Clinical Trial Registry NCT01663636).     

Use of telephone and SMS reminders to improve attendance at hospital appointments: a systematic review

Patients failing to attend hospital appointments contribute to inefficient use of resources. We conducted a systematic review of studies providing a reminder to patients by phone, short message service (SMS) or automated phone calls. A PubMed search was conducted to identify articles published after 1999, describing studies of non-attendance at hospital appointments. In addition, we searched the references in the included papers. In total, 29 studies were included in the review. Four had two intervention arms which were treated as independent studies, giving a total of 33 estimates. The papers were analysed by two observers independently. A study quality score was developed and used to weight the data. Weighted means of the absolute and the relative changes in non-attendance were calculated. All studies except one reported a benefit from sending reminders to patients prior to their appointment. The synthesis suggests that the weighted mean relative change in non-attendance was 34% of the baseline non-attendance rate. Automated reminders were less effective than manual phone calls (29% vs 39% of baseline value). There appeared to be no difference in non-attendance rate, whether the reminder was sent the day before the appointment or the week before. Cost and savings were not measured formally in any of the papers, but almost half of them included cost estimates. The average cost of using either SMS, automated phone calls or phone calls was ?.41 per reminder. Although formal evidence of cost-effectiveness is lacking, the implication of the review is that all hospitals should consider using automated reminders to reduce non-attendance at appointments.     

Mobile phone reminders for enhancing uptake,completeness and timeliness of routine childhood immunization in low and middle income countries: A systematic review and meta-analysis

Immunization remains one of the most effective public health interventions offering protection for children from vaccine preventable diseases. However, many children living in low- and- middle income countries do not get adequate immunization due to several factors. Mobile phone reminder interventions have shown great potential in enhancing a number of immunization outcomes. However, the evidence supporting its use in these countries is vague. This systematic review was conducted to provide evidence for mobile phone reminder in enhancing immunization uptake, completeness and timeliness. This review was conducted in accordance to the PRISMA recommendations. Three online databases; PubMed, Cochrane Library and African Journals Online, were systematically searched for potentially relevant studies. Screening of records (titles/abstracts from and full-texts) was done using Covidence. Meta-analyses were conducted using the Cochrane Collaboration Review Manager (v5.4). The GRADEpro was used to evaluate the certainty of evidence/summary of findings. Eleven RCTs assessing immunization uptake, completeness and/or timeliness by means of SMS, phone calls or a combination of voice message and SMS were included in both quantitative and qualitative synthesis. Overall, the included studies were of moderate quality. Majority of the included studies indicated that mobile phone reminders were beneficial. Meta-analyses indicated that using mobile phone reminder interventions for the review outcomes was of variable effect with high level of heterogeneity. A combination of voice message and SMS has a greater effect followed by phone calls then SMS reminders for immunization completeness. The use of SMS for immunization uptake and timeliness were largely insignificant (p > 0.05). Furthermore, evidence to support the efficacy of mobile phone reminder from the GRADE synthesis was between low and moderate. Mobile phone reminders, particularly a combination of voice message + SMS and perhaps phone calls appears to be more effective in enhancing immunization outcomes. However, more studies are required in view of methodological inadequacies in existing studies.     

Improving medication adherence in diabetes type 2 patients through Real Time Medication Monitoring: a Randomised Controlled Trial to evaluate the effect of monitoring patients' medication use combined with short message service (SMS) reminders

Background  

Innovative approaches are needed to support patients' adherence to drug therapy. The Real Time Medication Monitoring (RTMM) system offers real time monitoring of patients' medication use combined with short message service (SMS) reminders if patients forget to take their medication. This combination of monitoring and tailored reminders provides opportunities to improve adherence. This article describes the design of an intervention study aimed at evaluating the effect of RTMM on adherence to oral antidiabetics.     

The impacts of email reminder/recall on adolescent influenza vaccination

BackgroundWe sought to: (1) explore the feasibility of using email for seasonal influenza vaccination reminders to parents of adolescents and (2) assess influenza vaccination rates among adolescents whose parents were randomized to either receive or not receive email reminders.MethodsEmail addresses were obtained for parents of patients 10–18 years from 4 practices in Michigan. Addresses were randomized to either receive email reminders, or not. Reminder messages were sent during October 2012-March 2013 (Season 1) and October 2013-March 2014 (Season 2). Vaccination status was determined 60 days following the last email reminder for each season using the statewide Michigan Care Improvement Registry (MCIR); per protocol bivariate and multivariate logistic regression analyses were conducted to evaluate reminder notification.ResultsAfter email cleaning, testing, and matching with MCIR, approximately half of email addresses (2348 of 5312 in Season 1; 3457 of 6549 in Season 2) were randomized. Bivariate analyses found that influenza vaccination within 60 days after notification date was similar among those notified (34%) versus not notified (29%) in both Season 1 (p = 0.06) and Season 2 (39% vs. 37%, p = 0.20). However, multivariate models adjusted for season, site, and receipt of notification in two seasons found a higher likelihood of influenza vaccination among children that received notification (aOR = 1.28, 95% CI = 1.09, 1.51); in addition, differences in influenza vaccination were also observed between practice sites (range: p = 0.15 to p < 0.001).ConclusionsWe found that practice-based email influenza vaccine reminders to parents of adolescents are feasible, but not without complications. Our study demonstrates that email reminders from practices can yield increases in influenza vaccination rates among adolescents. Practices should consider email as an option for influenza reminders and establish business practices for collecting and maintaining patient email addresses.This study is registered at www.ClinicalTrials.gov id #NCT01732315.     

Improving influenza vaccination performance in an HMO setting: the use of computer-generated reminders and peer comparison feedback.

We evaluated a program for improving influenza immunization performance in a health maintenance organization (HMO). The HMO implemented several interventions successively from 1984-87: a postcard reminder to members at high risk for complications of influenza, a computer-generated reminder to the physician at the time of any primary care visit by high-risk patients, performance feedback to chiefs of service, and, finally, retrospective feedback to each physician comparing his/her performance with that of the other physicians. We examined immunization rates for a group of members older than age 65, a high-risk group under age 65, and a group of diabetic members who had not been subject to the reminders (vs a group who had been covered by the program). Vaccination rates were increased in those diabetic members who received reminders. Nevertheless, among members younger and older than age 65 whose experience was observed over three flu seasons, a significant increase in vaccination rates was not achieved until physician feedback was added to the program. We conclude that each element of the reminder and feedback program has contributed to the overall increase in vaccination rates at the HMO and that effective ongoing influenza immunization programs can be implemented in practice settings with appropriate systems support.     

The effect of various types of patients’ reminders on the uptake of pneumococcal vaccine in adults: A randomized controlled trial

BackgroundInvasive pneumococcal disease is one of the most important vaccine-preventable diseases threatening the adult community due to missed opportunities for vaccination. This study compares the effect of three different types of patient reminder system on adulthood Streptococcus pneumoniae immunization in a primary care setting.MethodsThe study targeted patients aged 40 and older eligible for pneumococcal vaccine, but did not receive it yet (89.5% of 3072 patients) based on their electronic medical records in a family medicine center in Beirut. The sample population was randomized using an automated computer randomization system into six equal groups, receiving short phone calls, short text messaging system (sms-text) or e-mails each with or without patient education. Each group received three identical reminders spaced by a period of four weeks. Documentation of vaccine administration was then added to the longitudinal electronic patient record. The primary outcome was the vaccine administration rate in the clinics.ResultsOf the eligible patients due for the pneumococcal 23-polyvalent vaccine, 1380 who had mobile phone numbers and e-mails were randomized into six equal intervention groups. The various reminders increased vaccination rate to 14.9%: 16.5% of the short phone calls group, 7.2% of the sms-text group and 5.7% of the e-mail group took the vaccine. The vaccination rate was independent of the age, associated education message and the predisposing condition.ConclusionUse of electronic text reminders via e-mails and mobile phones seems to be a feasible and sustainable model to increase pneumococcal vaccination rates in a primary care center.     

Suitability of an electronic reminder device for measuring drug adherence in elderly patients with complex medication

We evaluated an electronic reminder device for detecting non-adherence in elderly patients with complex medication regimens. Randomly selected, home-living elderly patients were studied. The patients were aged over 65 years and were taking more than four drugs. Patients received an electronic reminder device which contained a GSM communications module. They were visited three times over a one-year period by a nurse who counted their medicine supply. We compared the adherence measured by the electronic device with the actual adherence measured by the pill count. Almost half of the 315 patients dropped out of the study for various reasons, so the calculations were performed on 168 patients. The adherence measured by the electronic reminder system was 79% and was 92% measured by pill count (P<0.0001). The limits of agreement estimated by a Bland-Altman analysis were -57 to +30. We also compared electronically measured adherence at morning/evening intake times with pill count adherence in the morning/evening only. For the pill count, there was almost no difference between morning and evening adherence rates (93%). For electronic measurement, adherence rates were lower in the evening (75%) than in the morning (81%). Electronic reminders were less reliable than the pill count in measuring adherence. However, the electronic system may be a useful supplement to other, more time consuming methods for measuring adherence.     

Patient views on reminder letters for influenza vaccinations in an older primary care patient population: a mixed methods study

OBJECTIVES: To explore the perspectives of older adults on the acceptability of reminder letters for influenza vaccinations. METHODS: We randomly selected 23 family physicians from each Family Health and Primary Care network participating in a demonstration project designed to increase the delivery of preventive services in Ontario. From the roster of each physician, we surveyed 35 randomly selected patients over 65 years of age who recently received a reminder letter regarding influenza vaccinations from their physician. The questionnaires sought patient perspectives on the acceptability and usefulness of the letter. We also conducted follow-up telephone interviews with a subgroup of respondents to explore some of the survey findings in greater depth. RESULTS: 85.3% (663/767) of patients completed the questionnaire. Sixty-five percent of respondents recalled receiving the reminder (n=431), and of those, 77.3% found it helpful. Of the respondents who recalled the letter and received a flu shot (n=348), 11.2% indicated they might not have done so without the letter. The majority of respondents reported that they would like to continue receiving reminder letters for influenza vaccinations (63.0%) and other preventive services (77.1%) from their family physician. The interview participants endorsed the use of reminder letters for improving vaccination coverage in older adults, but did not feel that the strategy was required for them personally. CONCLUSIONS: The general attitude of older adults towards reminder letters was favourable, and the reminders appear to have contributed to a modest increase in influenza vaccination rates.     

Automated telephone reminder messages can assist electronic diabetes care

Telephone reminder systems have been used to assist in the treatment of many chronic diseases. However, it is unclear if these systems can increase medication and appointment adherence in patients with diabetes without direct patient-provider telephone contact. We tested the feasibility of using an automated telephone reminder system (ATRS) to deliver reminder messages to 253 adults with diabetes enrolled in a randomized controlled trial. Eighty-four percent of the patients were able to register using voice recognition and at least one reminder was delivered to 95% of registered patients over a period of 7.5 months. None of the demographic features studied predicted a patient's ability to enroll or to receive reminder calls. At the end of the study, 63% of patients indicated that they wished to continue to receive ATRS calls. The level of system use as determined by the number of received reminder calls was not associated with a change in the number of physician visits or diabetes-related laboratory tests during follow-up. The clinical benefits and sustainability of ATRS remain unproven, but our results indicate that an automated reminder system can be effective for providing messages to a large group of older patients with diabetes.     

A randomised controlled trial of SMS messaging and calendar reminders to improve vaccination timeliness in infants

BackgroundThe effectiveness of SMS reminders in improving vaccination coverage has been assessed previously, with effectiveness varying between settings. However, there are very few studies on their effect on the timeliness of vaccination.DesignUnblinded, randomised controlled trial with blocked sampling.Methods1594 Australian infants and young children were recruited to assess the impact of (1) SMS reminders only, (2) a personalised calendar, (3) SMS reminder and personalised calendar and (4) no intervention, on receipt of vaccine within 30 days of the due date. Outcomes were measured for receipt of vaccines due at 2, 4, 6, 12 and 18 months of age. A post-hoc assessment was also conducted of the impact of a new national “No jab No Pay” policy introduced during the trial, which removed philosophical objections as an exemption for financial penalties for non-vaccination.ResultsThere was a statistically significant improvement in on-time vaccination only at the 12 month schedule point amongst infants who received SMS reminders alone (RR 1.09, 95% CI 1.01–1.18) or in combination with a personalised calendar (1.11, CI 1.03–1.20) compared to controls. This impact was limited to participants who had received one or more previous doses late. No statistically significant impacts of calendar interventions alone were seen. There was a high rate of on-time compliance amongst control participants − 95%, 86%, 80%, 74% at the 4, 6, 12 and 18 month schedule points respectively, which increased more than 10 percentage points after implementation of the “No Jab, No Pay” policy.ConclusionsSMS reminders are more effective in improving timeliness where pre-existing compliance is lower, but the 18 month schedule point appeared to be less amenable to intervention. Australia and New Zealand Clinical Trial Registration No. ACTRN12614000970640.     

The use of patient and physician reminders for preventive services: results from a National Study of Physician Organizations

BACKGROUND: Clinical preventive services improve patient health, and reminder systems can increase the use of such services. However, physician organizations often underutilize clinical preventive service reminders. Little is known about the incentives, capabilities, and organizational characteristics associated with the use of reminders by physician organizations. METHODS: The predictors of patient and physician reminder system use were examined in a sample of 1,104 US physician organizations. The cross-sectional sample was obtained through a telephone survey with a 70% response rate. RESULTS: Fifty-one percent of physician organizations used mammogram reminders, 41% used influenza immunization reminders, and 26% used eye exam reminders for patients. Eighteen percent of physician organizations used computer-generated reminders to physicians. Required reporting of data (P = 0.0006), public recognition for quality (P = 0.0002), and IT capabilities (P < 0.0001) were strongly associated with patient reminder use. Medical groups were more likely to use patient-level reminders than independent practice associations (IPAs) (P < 0.0001). Physician reminder use was related to required reporting of data (P < 0.0001) and IT capabilities (P < 0.0001). CONCLUSIONS: Physician organizations have relatively low use of preventive service reminders to patients and physicians. Offering quality incentives to physician organizations and improving their IT capabilities may increase the use of preventive service reminders and improve the delivery of preventive care.     

The effect of short messaging service text on non-attendance in a general ophthalmology clinic

To our knowledge there have been no previous studies that have examined the effect of short messaging service (SMS) text messaging reminders to both mobile and landlines on the 'did not attend' (DNA) rate in adult hospital clinic attendees. Our aim was to determine the effectiveness of a text messaging reminder in improving attendance in return general ophthalmology clinic patients. Ophthalmology clinic patients requiring a follow-up appointment were invited to enter the study. An information leaflet was provided and patients were contacted two weeks before their scheduled appointment by way of a customized text message to either the mobile phone or landline. The non-attendance rate compared with historic non-attendance rate was recorded. Two hundred and one patients were recruited. The historic DNA rate was 12%. The DNA rate in the SMS text reminder group was reduced to 5.5% (11 patients). The historic 'Could not attend' (CNA) rate of 6% had been reduced to 2% (4 patients). Forty-seven percent of patients used mobile phone technology with text messaging capability and 69% responded to the text reminder. In conclusion, routine SMS texting is a cost-effective means of reducing DNAs and should become standard practice. In addition, two-way messaging could allow for further efficiency as advance notification of patient cancellations facilitates re-scheduling of alternative patients.     

The utility of providing automated medication dose reminders to young children on chronic medication

We investigated the effect of text message reminders about medication administration. The study concerned children with cystic fibrosis. We provided 20 children (aged 5-12 years) with pagers that they could customize. For the first two weeks, we sent friendly text messages (non-reminder content) near medication times to acquaint them with the use of the pager. For the second two weeks, we sent messages reminding children to take their medications. The parents completed a survey to assess the child's overall use of the pager and degree of participation in medication management. Sixteen out of 20 children completed the study. Of these, 14 children (88%) were able to help notify parents when medications were due. Children as young as seven years of age may be able to receive reminders about medication administration events. The pilot study demonstrated the feasibility of involving younger children in pager technology related to medication adherence.     

Computer-generated physician and patient reminders. Tools to improve population adherence to selected preventive services

Despite an emerging consensus on appropriate preventive services, a minority of patients receive them. A study was undertaken to assess the impact of computer-generated reminders to adult patients, their physicians, or both patients and physicians on adherence to five recommended preventive services: cholesterol measurements, fecal occult blood testing, mammography, Papanicolaou smears, and tetanus immunization. During the academic year 1988-1989, all 7397 adult patients and their 49 physicians in a university family medicine clinical practice were randomized by practice group into one of four study groups: control, physician reminders, patient reminders, and both physician and patient reminders. Adherence was defined in community-oriented terms: the percentage of patients within each group who had received the preventive service in the recommended interval. During the study period, adherence to four of the five preventive services increased significantly, with the largest increases in the physician and patient reminder group: cholesterol measurements increased from 19.5% to 38.1%, fecal occult blood testing 9.3% to 27.0%, mammography 11.4% to 27.1%, and tetanus immunization 23.4% to 35.4% (for each increase, P less than .0001, McNemar's chi-square test). In general, increases were greater in blacks and in patients with any form of insurance coverage. Computer-based physician and patient reminder systems have great promise of improving adherence to preventive services in primary care settings.     

Effect of mobile phone text messaging for improving the uptake of influenza vaccination in patients with rare diseases

ObjectivesInfluenza vaccine is recommended in some chronic medical conditions, including several rare diseases. The objectives of the study were to assess the effect of text message reminders on influenza vaccination uptake of patients with selected rare diseases and delayed vaccination, and to describe their characteristics.MethodsQuasi-experimental pre-post intervention study performed along the 2016 influenza vaccination campaign in the Autonomous Community of Madrid. Unvaccinated patients diagnosed with a selected rare disease were targeted for intervention. SMS were sent to them at least one month after the beginning of the campaign, in four consecutive weeks. Those with no mobile phones available or no certainty of message reception, were assigned as controls. The association between the reception of the SMS and vaccination uptake was assessed using multiple poisson regression models.ResultsOf 69.040 patients with delayed vaccination, 87.2% received an SMS reminder in the asigned contact mobile telephone. Global influenza vaccine coverage reached 41.3%. The uptake of influenza vaccine was significantly higher among those receiving the reminder (9.3% vs. 7.1% in the control group, p < 0.001). Those who received a SMS reminder were 30% more likely to uptake seasonal influenza vaccine. By sex and age, the reception of the reminder was associated with a significantly higher probability of vaccination in men ≥65 years with at least a concurrent chronic condition (IRR: 1.58, CI95%: 1.25–2.00). Among women, this higher probability was detected in those between 14 and 64 years of age (IRR: 1.41, CI95%: 1.22–1.63), and ≥65 years without concurrent chronic conditions (IRR: 1.40, CI95%: 1.05–1.89).ConclusionAlthough the intervention was modestly effective, it proved beneficial in some cases. It can be an additional strategy to improve vaccine uptake, since it is simple, feasible, affordable and easily scalable, particularly when immunization and target population data are available in population registries.