A total of 24 articles published between 2011 and 2019 were included in this review. Most studies took place in Western countries (United States being the major contributor (n=11)). The majority of articles reported the use of QR codes for nursing students (n=6). Article types included research articles, editorials, communications and commentaries. A summary of article characteristics is show in in Table 1.
The main uses of QR codes in healthcare education emerging from thematic analysis were as follows:
1) Increasing participant engagement
2) Just-in-time (JIT) learning
4) Training support
Table 2 summarises all articles included in this review.
Theme 1: Increasing participant engagement
Nine articles discussed ways in which QR codes could be utilised to enhance participant engagement [19–27]. These can be broadly divided into those focusing on anatomy teaching, formative assessment, case-based learning and engagement with publications.
Three articles discussed the application of QR codes for anatomy teaching [19, 26, 27]. Mogali et al reported how a medical student’s experience of an anatomy specimen museum could be enhanced by the use of QR codes  attached to specimens. This allowed further contextual information to be gained, such as annotated images and clinical histories. In this study, 78% of students agreed that QR codes were useful for learning and the majority of students agreed or strongly agreed that specimen information was easy to access via QR codes. Key benefits of QR codes cited by the author included its low-cost and adaptability in any learning environment. It also limits damage to specimens from actual handling. In a similar manner, Siderits et al used QR codes to facilitate the distribution of, and enhance the educational content at, tumour board presentations .
Two studies used QR codes to aid learning through formative assessment [19, 20]. From questionnaire responses, over 80% of students reported that they found QR codes to be more helpful than traditional learning aids. However, despite this, neither study demonstrated a positive impact on student examination performance compared to the control group. There were high levels of total engagement in both cases and students using QR codes for gross anatomy learning, in particular, appreciated the receipt of immediate feedback. The authors also discuss how their use can act as a cost-effective self-assessment solution .
Lin et al investigated the use of QR codes during a pharmacology course for third year nursing students in Taiwan [22, 23] and reported most participants held positive attitudes towards QR codes, with their utility for learning activities being cited as a key benefit. Lin noted that when used for case-based learning, a subset of students performed better in asking questions and discussions than they did prior to the introduction of QR codes.
Finally, an editorial by MacRae reported on the introduction of QR codes onto articles in the journal, Neurosurgery . This has allowed linking to further multimedia information and easier dissemination by readers.
The majority of the aforementioned studies demonstrated how students found QR codes easy to use [19–23] and had a desire to continue using them in the future for classroom exercises or otherwise [20–23].
Problems associated with implementation of QR codes for increasing engagement included: the requirement for internet access for full functionality [20, 23] and difficulties with downloading a QR code reader onto smartphones [19, 20].
For anatomy teaching, limitations were related to the sensitive information or images that may be contained within QR codes. Two studies therefore had to remind students that learning resources were for personal use only [19, 26]. Mogali et al password protected PDF documents that were linked to QR codes to prevent amendments and printing . Additionally, Traser et al indicated that students were reluctant to bring their phones into a gross anatomy laboratory .
Interestingly, 47% of students in Lin’s study declined to trial the use of QR codes because of eyestrain from the use of cellular devices and distractions from work by surfing the internet . Zurmehly et al. also noted that not all students had a smartphone . This problem was overcome during the study through pairing students without a smartphone with those who did have one. Other limitations discussed included the need to ensure QR codes were large enough and not wrinkled from the surface they were applied to; both of which would make it harder for the scanner to read.
Theme 2: Just-in-time (JIT) learning
Six articles discussed how QR codes can be used for JIT learning [28–33]. This is a paradigm in which training is available on demand and can be accessed by staff when needed . These applications can be broadly divided into those that allow reference to guidelines [29–31, 33] and those that contain information on how to perform a skill or use a piece of equipment [28, 30, 32]. For example, Tracey et al discuss the recording of video clips demonstrating step-by-step procedures for wound care, medication administration and Foley catheter insertion . Downer et al discuss the use of QR codes for using equipment such as blood pressure machines .
Articles on the use of QR codes for referencing include checking plastic surgery and immune-related adverse event guidelines [29, 33], allowing nurses to view the management guidelines for falls  and accessing doctor’s phone numbers, in a labour room . Rosario et al demonstrated that QR codes provide high levels of functionality, usability and usefulness . Gardiner et al perceived that QR codes have a significant role in disseminating information to both healthcare staff and patients, with environmental and cost benefits because QR codes can ‘never run out’ .
The majority of articles containing JIT learning for skills or equipment-use, are linked to a video clip that the user could watch [28, 32]. Benefits associated with this included decreasing the downtime of students as they no longer had to wait for a facilitator to demonstrate  and the portability of the videos from access on a smart device .
A number of studies [28, 31, 32] have reported how healthcare staff find QR codes suitable for JIT learning as they are convenient and allow access to material in their own time and at a suitable pace for them. Interestingly, Tracey et al noted how the response to the use of QR codes was overwhelmingly positive, particularly from the millennial generation .
Similar to other studies [19, 23], Jamu identified a reluctance to use devices in certain environments . In this case, a clinical environment in front of patients. Additionally, Jamu noted a need for technical support in those with ‘little or no’ previous IT experience.
Theme 3: Simulation
Four articles discussed the adoption of QR codes to aid with simulation [35–38]. Damjanovic discussed the use of QR codes in creating a low-budget point-of-care ultrasound simulator . QR codes were printed and stuck on an ultrasound phantom for practice. This provided a less resource intensive solution compared to radio frequency identification or near-field communication alternatives that require hardware. However, it was acknowledged that there is a time cost related to ensuring correct coding for corresponding video clips.
A novel use of QR codes in augmented reality (AR) integrated simulation training was reported by Carlson . In this study, an average of five QR codes were used per scenario to act as a marker in order to trigger virtual images from AR software. Facilitators also had QR codes that could be scanned in order to validate a correct action. Perceptions related to this integrated simulation were rated positively, although no specific questions relating to the use of QR codes were asked. Users also felt that this particular application was a not a replacement for more traditional simulation teaching.
Two studies discuss QR code application in combination with gamification to allow for the identification of a simulated patient or medication or in order to identify the user involved [35, 37]. Problems were identified with their use during these studies. These included difficulties with the QR code scanner reading the code during a game  and, as previously discussed, difficulties in co-ordinating a reliable internet connection and downloading a QR code scanner .
Theme 4: Training support
Four articles explore how QR codes can be used to improve trainee experience, either through improvement in feedback methods [39–41] or by recording procedures undertaken in a log book .
Sobhani et al  and Reynolds et al  both investigated how feedback could be received through assigning an individual QR code to each student or resident that could then be scanned by a faculty member. In both cases, it was demonstrated that faculty found the QR-linked feedback form superior to the paper alternative.
Sobhani et al demonstrated that faculty found the feedback method easier to understand and navigate, with faculty feeling more comfortable to approach students . However, students from the study did not report increased efficacy to elicit feedback when compared to the paper form.
Reynolds findings from a mix of faculty and students indicated that the QR form provided improved educational benefits . Overall, more evaluations were also submitted by residents over 6 months compared to paper assessments.
Snyder et al compared the use of QR feedback forms at 15 family medicine clerkship sites across the United States to online or paper alternatives . It was found that the QR feedback forms were associated with the highest usability score and took the shortest amount of time to prepare by students. Although, adoption of the QR feedback forms was challenged by wireless network limitations.
Avidan et al discussed the use of QR codes for improving the logging of cases for anaesthetic trainees . In this study, QR codes were generated by a computer system at the conclusion of each case containing information such as the date of surgery, type of surgery and type of anaesthesia. This was then scanned by a trainee using their smartphone to store the data in their own spreadsheet. Avidan et al hypothesised that this method would reduce reliance on the IT department, whom trainees contacted to receive a list of all their cases at the end of their residency. It would also ensure that trainees did not come to the end of their residency and realise that they had not performed enough of a particular type of procedure, at which point the deficit would be harder to correct.
Evaluation was performed prior to the introduction of QR codes and then at 3 and 6 months after introduction. Residents rated that usability of the technology highly and most stated they would recommend the use of QR codes for case logging to colleagues. The overall rate of case logging had increased by over 45% when compared to before the introduction of QR codes.