SMSascha Miller

Sascha Miller

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Sascha Miller has a total of 50 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Implementing a Digital Physical Activity Intervention for Older Adults: Qualitative Study

    by Cherish Boxall, Laura Dennison, Sascha Miller, Judith Joseph, Kate Morton, Jenny Corser, Joanna Kesten, Asgar Electicwala, Max J Western, Stephen Lim, et al.

    Background: Physical activity (PA) in older adults can prevent, treat, or offset symptoms and deterioration from various health conditions and help maintain independence. However, most older adults are insufficiently active. Digital interventions have the potential for high reach at low cost. Objective: This paper reports on the implementation of “Active Lives,” a digital intervention developed specifically for older adults. Methods: This study had a qualitative design. The implementation team approached a range of National Health Service, public health, community, and third-sector organizations in the United Kingdom to offer Active Lives to as large and diverse groups of older adults as possible. Alongside real-world implementation activities, research was conducted to explore what supports and inhibits the implementation of a digital intervention for PA in older adults. Data collection involved interviews with implementation partners (n=15) and the implementation team (n=3) plus extensive field notes from stakeholder communications. Inductive thematic analysis was used to analyze the data. Results: Five broad themes were developed, capturing implementation barriers and facilitators. These were (1) complex and opaque networks and influencers, (2) forming an understanding of Active Lives and its fit, (3) a landscape of competition and conflicting interests, (4) navigating unclear approval processes, and (5) shifting strategies: small and effortful to high reach and passive. Identifying key decision makers proved arduous, consuming significant time and resources, and proposals from enthusiastic implementation partners often proved impractical or overly burdensome. Health care professionals demonstrated a comprehensive understanding of the potential benefits of digital interventions in alleviating operational burdens and improving patient care. However, stakeholders from disparate sectors held reservations about digital intervention and had different views on the best approaches to supporting PA among older adults. This discord was exacerbated by conflicts with existing local initiatives, such as group exercise programs, which occasionally hindered the implementation of Active Lives. Furthermore, bureaucratic hurdles within National Health Service trust approval processes acted as formidable obstacles, dampening progress and resolve, highlighting the need for guidance in identifying sustainable and scalable practices. Conclusions: The findings highlight important implementation challenges to digital PA interventions for older adults such as bureaucratic barriers and alignment with ongoing initiatives. This research emphasizes the necessity for strategic direction and multilevel guidance to efficiently implement digital interventions for PA among community-dwelling older adults.


  • Open Access

    A Digital Intervention for Respiratory Tract Infections (Internet Dr): Process Evaluation to Understand How to Support Self-care for Minor Ailments

    by Sascha Miller, Lucy Yardley, Peter Smith, Mark Weal, Alexander Anderson, Beth Stuart, Paul Little, Leanne Morrison

    Background: Approximately 57 million physician appointments annually in the United Kingdom are for minor ailments. These illnesses could be self-cared for, which would potentially lower patients’ anxiety, increase their confidence, and be more convenient. In a randomized controlled trial of the Internet Dr digital intervention, patients with access to the intervention had fewer consultations for respiratory tract infections (RTIs). Having established intervention efficacy, further examination of trial data is required to understand how the intervention works. Objective: This paper reports a process evaluation of Internet Dr usage by the intervention group. The evaluation aims to demonstrate how meaningful usage metrics (ie, interactions that are specific and relevant to the intervention) can be derived from the theoretical principles underlying the intervention, then applied to examine whether these interactions are effective in supporting self-care for RTIs, for whom, and at what time. Methods: The Internet Dr trial recorded patients’ characteristics and usage data over 24 weeks. At follow-up, users reported whether their levels of enablement to cope with their illness changed over the trial period. The Medical Research Council process evaluation guidance and checklists from the framework for Analyzing and Measuring Usage and Engagement Data were applied to structure research questions examining associations between usage and enablement. Results: Viewing pages containing advice on caring for RTIs were identified as a meaningful metric for measuring intervention usage. Almost half of the users (616/1491, 42.31%) viewed at least one advice page, with most people (478/616, 77.6%) accessing them when they initially enrolled in the study. Users who viewed an advice page reported increased enablement to cope with their illness as a result of having participated in the study compared with users who did not (mean 2.12, SD 2.92 vs mean 1.65, SD 3.10; mean difference 0.469, 95% CI 0.082-0.856). The target population was users who had visited their general practitioners for an RTI in the year before the trial, and analyses revealed that this group was more likely to access advice pages (odds ratio 1.35, 95% CI 1.159-1.571; P<.001). Conclusions: The process evaluation identifies viewing advice pages as associated with increased enablement to self-care, even when accessed in the absence of a RTI, meaning that dissemination activities need not be restricted to targeting users who are ill. The intervention was effective at reaching the target population of users who had previously consulted their general practitioners. However, attrition before reaching advice pages was high, highlighting the necessity of prioritizing access during the design phase. These findings provide guidance on how the intervention may be improved and disseminated and have wider implications for minor ailment interventions.


  • Open Access

    Infection control in the home: a qualitative study exploring perceptions and experiences of adhering to protective behaviours in the home during the COVID-19 pandemic

    by Katherine Morton, Lauren Towler, Julia Groot, Sascha Miller, Ben Ainsworth, James Denison-Day, Cathy Rice, Jennifer Bostock, Merlin Willcox, Paul Little, et al.

    Objectives: We sought to explore people’s experiences and perceptions of implementing infection control behaviours in the home during the COVID-19 pandemic, guided by an online behavioural intervention. Design: Inductive qualitative study. Setting: UK public during the COVID-19 pandemic. Participants: Thirteen people took part in telephone interviews, and 124 completed a qualitative open-text survey. All were recruited from the public. Most survey participants were aged over 60 years, while interview participants were more distributed in age. Most reported being at increased risk from COVID-19, and were white British. Intervention: Online behavioural intervention to support infection control behaviours in the home during the COVID-19 pandemic. Data collection: Telephone think-aloud interviews and qualitative survey data. Data analysis: The think-aloud interview data and qualitative survey data were analysed independently using inductive thematic analysis. The findings were subsequently triangulated. Results: Thematic analysis of the telephone interviews generated seven themes : perceived risk; belief in the effectiveness of protective behaviours; acceptability of distancing and isolation; having capacity to perform the behaviours; habit forming reduces effort; having the confidence to perform the behaviours; and social norms affect motivation to engage in the behaviours . The themes identified from the survey data mapped well onto the interview analysis. Isolating and social distancing at home were less acceptable than cleaning and handwashing, influenced by the need for intimacy with household members. This was especially true in the absence of symptoms and when perceived risk was low. People felt more empowered when they understood that even small changes, such as spending some time apart, were worthwhile to reduce exposure and lessen viral load. Conclusions: The current study provided valuable insight into the acceptability and feasibility of protective behaviours, and how public health guidance could be incorporated into a behaviour change intervention for the public during a pandemic.


  • Open Access

    A Web-Based Intervention (Germ Defence) to Increase Handwashing During a Pandemic: Process Evaluations of a Randomized Controlled Trial and Public Dissemination

    by Sascha Miller, Ben Ainsworth, Mark Weal, Peter Smith, Paul Little, Lucy Yardley, Leanne Morrison

    Background: Washing hands helps prevent transmission of seasonal and pandemic respiratory viruses. In a randomized controlled trial (RCT) during the swine flu outbreak, participants with access to a fully automated, digital intervention promoting handwashing reported washing their hands more often and experienced fewer respiratory tract infections than those without access to the intervention. Based on these findings, the intervention was adapted, renamed as “Germ Defence,” and a study was designed to assess the preliminary dissemination of the intervention to the general public to help prevent the spread of seasonal colds and flu. Objective: This study compares the process evaluations of the RCT and Germ Defence dissemination to examine (1) how web-based research enrollment procedures affected those who used the intervention, (2) intervention usage in the 2 contexts, and (3) whether increased intentions to wash hands are replicated once disseminated. Methods: The RCT ran between 2010 and 2012 recruiting participants offline from general practices, with restricted access to the intervention (N=9155). Germ Defence was disseminated as an open access website for use by the general public from 2016 to 2019 (N=624). The process evaluation plan was developed using Medical Research Council guidance and the framework for Analyzing and Measuring Usage and Engagement Data. Both interventions contained a goal-setting section where users self-reported current and intended handwashing behavior across 7 situations. Results: During web-based enrolment, 54.3% (17,511/32,250) of the RCT participants dropped out of the study compared to 36.5% (358/982) of Germ Defence users. Having reached the start of the intervention, 93.8% (8586/9155) of RCT users completed the core section, whereas 65.1% (406/624) of Germ Defence users reached the same point. Users across both studies selected to increase their handwashing in 5 out of 7 situations, including before eating snacks (RCT mean difference 1.040, 95% CI 1.016-1.063; Germ Defence mean difference 0.949, 95% CI 0.766-1.132) and after blowing their nose, sneezing, or coughing (RCT mean difference 0.995, 95% CI 0.972-1.019; Germ Defence mean difference 0.842, 95% CI 0.675-1.008). Conclusions: By comparing the preliminary dissemination of Germ Defence to the RCT, we were able to examine the potential effects of the research procedures on uptake and attrition such as the sizeable dropout during the RCT enrolment procedure that may have led to a more motivated sample. The Germ Defence study highlighted the points of attrition within the intervention. Despite sample bias in the trial context, the intervention replicated increases in intentions to handwash when used “in the wild.” This preliminary dissemination study informed the adaptation of the intervention for the COVID-19 health emergency, and it has now been disseminated globally. Trial Registration: ISRCTN Registry ISRCTN75058295; https://www.isrctn.com/ISRCTN75058295


  • Open Access

    Primary Care implementation of Germ Defence, a digital behaviour change intervention to improve household infection control during the COVID-19 pandemic: A structured summary of a study protocol for a randomised controlled trial

    by Jeremy Horwood, Melanie Chalder, Ben Ainsworth, James Denison-Day, Frank de Vocht, Martha M. C. Elwenspoek, Pippa Craggs, Rachel Denholm, Jonathan Sterne, Cathy Rice, et al.

    Objectives: To examine the effectiveness of randomising dissemination of the Germ Defence behaviour change website via GP practices across England UK. Trial design: A two-arm (1:1 ratio) cluster randomised controlled trial implementing Germ Defence via GP practices compared with usual care. Participants: Setting: All Primary care GP practices in England. Participants: All patients aged 16 years and over who were granted access by participating GP practices. Intervention and comparator: Intervention: We will ask staff at GP practices randomised to the intervention arm to share the weblink to Germ Defence with all adult patients registered at their practice during the 4-month trial implementation period and care will otherwise follow current standard management. Germ Defence is an interactive website (http://GermDefence.org/) employing behaviour change techniques and practical advice on how to reduce the spread of infection in the home. The coronavirus version of Germ Defence helps people understand what measures to take and when to take them to avoid infection. This includes hand washing, avoiding sharing rooms and surfaces, dealing with deliveries and ventilating rooms. Using behaviour change techniques, it helps users think through and adopt better home hygiene habits and find ways to solve any barriers, providing personalised goal setting and tailored advice that fits users’ personal circumstances and problem solving to overcome barriers. Comparator: Patients at GP practices randomised to the usual care arm will receive current standard management for the 4-month trial period after which we will ask staff to share the link to Germ Defence with all adult patients registered at their practice. Main outcomes: The primary outcome is the effects of implementing Germ Defence on prevalence of all respiratory tract infection diagnoses during the 4-month trial implementation period. The secondary outcomes are: 1) incidence of COVID-19 diagnoses 2) incidence of COVID-19 symptom presentation 3) incidence of gastrointestinal infections 4) number of primary care consultations 5) antibiotic usage 6) hospital admissions 7) uptake of GP practices disseminating Germ Defence to their patients 8) usage of the Germ Defence website by individuals who were granted access by their GP practice Randomisation: GP practices will be randomised on a 1:1 basis by the independent Bristol Randomised Trials Collaboration (BRTC). Clinical Commission Groups (CCGs) in England will be divided into blocks according to region, and equal numbers in each block will be randomly allocated to intervention or usual care. The randomisation schedule will be generated in Stata statistical software by a statistician not otherwise involved in the enrolment of general practices into the study. Blinding (masking): The principal investigators, the statistician and study collaborators will remain blinded from the identity of randomised practices until the end of the study. Numbers to be randomised (sample size): To detect planned effect size (based on PRIMIT trial, Little et al, 2015): 11.1 million respondents from 6822 active GP practices. Assuming 25% of these GP practices will engage, we will contact all GP practices in England spread across 135 Clinical Commissioning Groups. Trial status: Protocol version 2.0, dated 13 January 2021. Implementation is ongoing. The implementation period started on 10 November 2020 and will end on 10 March 2021. Trial registration: This trial was registered in the ISRCTN registry (isrctn.com/ ISRCTN14602359) on 12 August 2020. Full protocol: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.


  • Open Access

    Infection Control Behavior at Home During the COVID-19 Pandemic: Observational Study of a Web-Based Behavioral Intervention (Germ Defence)

    by Ben Ainsworth, Sascha Miller, James Denison-Day, Beth Stuart, Julia Groot, Cathy Rice, Jennifer Bostock, Xiao-Yang Hu, Katherine Morton, Lauren Towler, et al.

    Background: To control the COVID-19 pandemic, people should adopt protective behaviors at home (self-isolation, social distancing, putting shopping and packages aside, wearing face coverings, cleaning and disinfecting, and handwashing). There is currently limited support to help individuals conduct these behaviors. Objective: This study aims to report current household infection control behaviors in the United Kingdom and examine how they might be improved. Methods: This was a pragmatic cross-sectional observational study of anonymous participant data from Germ Defence between May 6-24, 2020. Germ Defence is an open-access fully automated website providing behavioral advice for infection control within households. A total of 28,285 users sought advice from four website pathways based on household status (advice to protect themselves generally, to protect others if the user was showing symptoms, to protect themselves if household members were showing symptoms, and to protect a household member who is at high risk). Users reported current infection control behaviors within the home and intentions to change these behaviors. Results: Current behaviors varied across all infection control measures but were between sometimes (face covering: mean 1.61, SD 1.19; social distancing: mean 2.40, SD 1.22; isolating: mean 2.78, SD 1.29; putting packages and shopping aside: mean 2.75, SD 1.55) and quite often (cleaning and disinfecting: mean 3.17, SD 1.18), except for handwashing (very often: mean 4.00, SD 1.03). Behaviors were similar regardless of the website pathway used. After using Germ Defence, users recorded intentions to improve infection control behavior across all website pathways and for all behaviors (overall average infection control score mean difference 0.30, 95% CI 0.29-0.31). Conclusions: Self-reported infection control behaviors other than handwashing are lower than is optimal for infection prevention, although handwashing is much higher. Advice using behavior change techniques in Germ Defence led to intentions to improve these behaviors. Promoting Germ Defence within national and local public health and primary care guidance could reduce COVID-19 transmission.


  • Open Access

    A Web-Based Intervention (Germ Defence) to Increase Handwashing During a Pandemic: Process Evaluations of a Randomized Controlled Trial and Public Dissemination (Preprint)

    by Sascha Miller, Ben Ainsworth, Mark Weal, Peter Smith, Paul Little, Lucy Yardley, Leanne Morrison

    BACKGROUND Washing hands helps prevent transmission of seasonal and pandemic respiratory viruses. In a randomized controlled trial (RCT) during the swine flu outbreak, participants with access to a fully automated, digital intervention promoting handwashing reported washing their hands more often and experienced fewer respiratory tract infections than those without access to the intervention. Based on these findings, the intervention was adapted, renamed as “Germ Defence,” and a study was designed to assess the preliminary dissemination of the intervention to the general public to help prevent the spread of seasonal colds and flu. OBJECTIVE This study compares the process evaluations of the RCT and Germ Defence dissemination to examine (1) how web-based research enrollment procedures affected those who used the intervention, (2) intervention usage in the 2 contexts, and (3) whether increased intentions to wash hands are replicated once disseminated. METHODS The RCT ran between 2010 and 2012 recruiting participants offline from general practices, with restricted access to the intervention (N=9155). Germ Defence was disseminated as an open access website for use by the general public from 2016 to 2019 (N=624). The process evaluation plan was developed using Medical Research Council guidance and the framework for Analyzing and Measuring Usage and Engagement Data. Both interventions contained a goal-setting section where users self-reported current and intended handwashing behavior across 7 situations. RESULTS During web-based enrolment, 54.3% (17,511/32,250) of the RCT participants dropped out of the study compared to 36.5% (358/982) of Germ Defence users. Having reached the start of the intervention, 93.8% (8586/9155) of RCT users completed the core section, whereas 65.1% (406/624) of Germ Defence users reached the same point. Users across both studies selected to increase their handwashing in 5 out of 7 situations, including before eating snacks (RCT mean difference 1.040, 95% CI 1.016-1.063; Germ Defence mean difference 0.949, 95% CI 0.766-1.132) and after blowing their nose, sneezing, or coughing (RCT mean difference 0.995, 95% CI 0.972-1.019; Germ Defence mean difference 0.842, 95% CI 0.675-1.008). CONCLUSIONS By comparing the preliminary dissemination of Germ Defence to the RCT, we were able to examine the potential effects of the research procedures on uptake and attrition such as the sizeable dropout during the RCT enrolment procedure that may have led to a more motivated sample. The Germ Defence study highlighted the points of attrition within the intervention. Despite sample bias in the trial context, the intervention replicated increases in intentions to handwash when used “in the wild.” This preliminary dissemination study informed the adaptation of the intervention for the COVID-19 health emergency, and it has now been disseminated globally. CLINICALTRIAL ISRCTN Registry ISRCTN75058295; https://www.isrctn.com/ISRCTN75058295

  • Open Access

    A Digital Intervention for Respiratory Tract Infections (Internet Dr): Process Evaluation to Understand How to Support Self-care for Minor Ailments (Preprint)

    by Sascha Miller, Lucy Yardley, Peter Smith, Mark Weal, Alexander Anderson, Beth Stuart, Paul Little, Leanne Morrison

    BACKGROUND Approximately 57 million physician appointments annually in the United Kingdom are for minor ailments. These illnesses could be self-cared for, which would potentially lower patients’ anxiety, increase their confidence, and be more convenient. In a randomized controlled trial of the Internet Dr digital intervention, patients with access to the intervention had fewer consultations for respiratory tract infections (RTIs). Having established intervention efficacy, further examination of trial data is required to understand how the intervention works. OBJECTIVE This paper reports a process evaluation of Internet Dr usage by the intervention group. The evaluation aims to demonstrate how meaningful usage metrics (ie, interactions that are specific and relevant to the intervention) can be derived from the theoretical principles underlying the intervention, then applied to examine whether these interactions are effective in supporting self-care for RTIs, for whom, and at what time. METHODS The Internet Dr trial recorded patients’ characteristics and usage data over 24 weeks. At follow-up, users reported whether their levels of enablement to cope with their illness changed over the trial period. The Medical Research Council process evaluation guidance and checklists from the framework for Analyzing and Measuring Usage and Engagement Data were applied to structure research questions examining associations between usage and enablement. RESULTS Viewing pages containing advice on caring for RTIs were identified as a meaningful metric for measuring intervention usage. Almost half of the users (616/1491, 42.31%) viewed at least one advice page, with most people (478/616, 77.6%) accessing them when they initially enrolled in the study. Users who viewed an advice page reported increased enablement to cope with their illness as a result of having participated in the study compared with users who did not (mean 2.12, SD 2.92 vs mean 1.65, SD 3.10; mean difference 0.469, 95% CI 0.082-0.856). The target population was users who had visited their general practitioners for an RTI in the year before the trial, and analyses revealed that this group was more likely to access advice pages (odds ratio 1.35, 95% CI 1.159-1.571; P<.001). CONCLUSIONS The process evaluation identifies viewing advice pages as associated with increased enablement to self-care, even when accessed in the absence of a RTI, meaning that dissemination activities need not be restricted to targeting users who are ill. The intervention was effective at reaching the target population of users who had previously consulted their general practitioners. However, attrition before reaching advice pages was high, highlighting the necessity of prioritizing access during the design phase. These findings provide guidance on how the intervention may be improved and disseminated and have wider implications for minor ailment interventions.

  • Open Access

    Effectiveness of digital interventions to improve household and community infection prevention and control behaviours and to reduce incidence of respiratory and/or gastro-intestinal infections: A rapid systematic review

    by Natalie Gold, Xiao-Yang Hu, Sarah Denford, Ru-Yu Xia, Lauren Towler, Julia Groot, Rachel Gledhill, Merlin Willcox, Ben Ainsworth, Sascha Miller, et al.

    Background: Digital interventions have potential to efficiently support improved hygiene practices to reduce transmission of COVID-19. Objective: To evaluate the evidence for digital interventions to improve hygiene practices within the community. Methods: We reviewed articles published between 01 January 2000 and 26 May 2019 that presented a controlled trial of a digital intervention to improve hygiene behaviours in the community. We searched MEDLINE, Embase, PsycINFO, Cochrane Controlled Register of Trials (CENTRAL), China National Knowledge Infrastructure and grey literature. Trials in hospitals were excluded, as were trials aiming at prevention of sexually transmitted infections; only target diseases with transmission mechanisms similar to COVID-19 (e.g. respiratory and gastrointestinal infections) were included. Trials had to evaluate a uniquely digital component of an intervention. Study designs were limited to randomised controlled trials, controlled before-and-after trials, and interrupted time series analyses. Outcomes could be either incidence of infections or change in hygiene behaviours. The Risk of Bias 2 tool was used to assess study quality. Results: We found seven studies that met the inclusion criteria. Six studies reported successfully improving self-reported hygiene behaviour or health outcomes, but only one of these six trials confirmed improvements using objective measures (reduced consultations and antibiotic prescriptions), Germ Defence. Settings included kindergartens, workplaces, and service station restrooms. Modes of delivery were diverse: WeChat, website, text messages, audio messages to mobiles, electronic billboards, and electronic personal care records. Four interventions targeted parents of young children with educational materials. Two targeted the general population; these also used behaviour change techniques or theory to inform the intervention. Only one trial had low risk of bias, Germ Defence; the most common concerns were lack of information about the randomisation, possible bias in reporting of behavioural outcomes, and lack of an analysis plan and possible selective reporting of results. Conclusion: There was only one intervention that was judged to be at low risk of bias, Germ Defence, which reduced incidence and severity of illness, as confirmed by objective measures. Further evaluation is required to determine the effectiveness of the other interventions reviewed.


  • Open Access

    Infection Control Behavior at Home During the COVID-19 Pandemic: Observational Study of a Web-Based Behavioral Intervention (Germ Defence) (Preprint)

    by Ben Ainsworth, Sascha Miller, James Denison-Day, Beth Stuart, Julia Groot, Cathy Rice, Jennifer Bostock, Xiao-Yang Hu, Katherine Morton, Lauren Towler, et al.

    BACKGROUND To control the COVID-19 pandemic, people should adopt protective behaviors at home (self-isolation, social distancing, putting shopping and packages aside, wearing face coverings, cleaning and disinfecting, and handwashing). There is currently limited support to help individuals conduct these behaviors. OBJECTIVE This study aims to report current household infection control behaviors in the United Kingdom and examine how they might be improved. METHODS This was a pragmatic cross-sectional observational study of anonymous participant data from Germ Defence between May 6-24, 2020. Germ Defence is an open-access fully automated website providing behavioral advice for infection control within households. A total of 28,285 users sought advice from four website pathways based on household status (advice to protect themselves generally, to protect others if the user was showing symptoms, to protect themselves if household members were showing symptoms, and to protect a household member who is at high risk). Users reported current infection control behaviors within the home and intentions to change these behaviors. RESULTS Current behaviors varied across all infection control measures but were between sometimes (face covering: mean 1.61, SD 1.19; social distancing: mean 2.40, SD 1.22; isolating: mean 2.78, SD 1.29; putting packages and shopping aside: mean 2.75, SD 1.55) and quite often (cleaning and disinfecting: mean 3.17, SD 1.18), except for handwashing (very often: mean 4.00, SD 1.03). Behaviors were similar regardless of the website pathway used. After using Germ Defence, users recorded intentions to improve infection control behavior across all website pathways and for all behaviors (overall average infection control score mean difference 0.30, 95% CI 0.29-0.31). CONCLUSIONS Self-reported infection control behaviors other than handwashing are lower than is optimal for infection prevention, although handwashing is much higher. Advice using behavior change techniques in Germ Defence led to intentions to improve these behaviors. Promoting Germ Defence within national and local public health and primary care guidance could reduce COVID-19 transmission.