Cost-effectiveness of telehealth for patients with raised cardiovascular disease risk: evidence from the Healthlines randomised controlled trial.

OBJECTIVES: To investigate the cost-effectiveness of a telehealth intervention for primary care patients with raised cardiovascular disease (CVD) risk. DESIGN: A prospective within-trial patient-level economic evaluation conducted alongside a randomised controlled trial. SETTING: Patients recruited through primary care, and intervention delivered via telehealth service. PARTICIPANTS: Adults with a 10-year CVD risk ≥20%, as measured by the QRISK2 algorithm, with at least 1 modifiable risk factor. INTERVENTION: A series of up to 13 scripted, theory-led telehealth encounters with healthcare advisors, who supported participants to make behaviour change, use online resources, optimise medication and improve adherence. Participants in the control arm received usual care. PRIMARY AND SECONDARY OUTCOME MEASURES: Cost-effectiveness measured by net monetary benefit at the end of 12 months of follow-up, calculated from incremental cost and incremental quality-adjusted life years (QALYs). Productivity impacts, participant out-of-pocket expenditure and the clinical outcome were presented in a cost-consequences framework. RESULTS: 641 participants were randomised-325 to receive the telehealth intervention in addition to usual care and 316 to receive only usual care. 18% of participants had missing data on either costs, utilities or both. Multiple imputation was used for the base case results. The intervention was associated with incremental mean per-patient National Health Service (NHS) costs of £138 (95% CI 66 to 211) and an incremental QALY gain of 0.012 (95% CI -0.001 to 0.026). The incremental cost-effectiveness ratio was £10 859. Net monetary benefit at a cost-effectiveness threshold of £20 000 per QALY was £116 (95% CI -58 to 291), and the probability that the intervention was cost-effective at this threshold value was 0.77. Similar results were obtained from a complete case analysis. CONCLUSIONS: There is evidence to suggest that the Healthlines telehealth intervention was likely to be cost-effective at a threshold of £20 000 per QALY. TRIAL REGISTRATION NUMBER: ISRCTN27508731; Results. Prospectively registered 05 July 2012.

Telehealth for patients at high risk of cardiovascular disease: pragmatic randomised controlled trial.

OBJECTIVE:  To assess whether non-clinical staff can effectively manage people at high risk of cardiovascular disease using digital health technologies. DESIGN:  Pragmatic, multicentre, randomised controlled trial. SETTING:  42 general practices in three areas of England. PARTICIPANTS:  Between 3 December 2012 and 23 July 2013 we recruited 641 adults aged 40 to 74 years with a 10 year cardiovascular disease risk of 20% or more, no previous cardiovascular event, at least one modifiable risk factor (systolic blood pressure ≥140 mm Hg, body mass index ≥30, current smoker), and access to a telephone, the internet, and email. Participants were individually allocated to intervention (n=325) or control (n=316) groups using automated randomisation stratified by site, minimised by practice and baseline risk score. INTERVENTIONS:  Intervention was the Healthlines service (alongside usual care), comprising regular telephone calls from trained lay health advisors following scripts generated by interactive software. Advisors facilitated self management by supporting participants to use online resources to reduce risk factors, and sought to optimise drug use, improve treatment adherence, and encourage healthier lifestyles. The control group comprised usual care alone. MAIN OUTCOME MEASURES:  The primary outcome was the proportion of participants responding to treatment, defined as maintaining or reducing their cardiovascular risk after 12 months. Outcomes were collected six and 12 months after randomisation and analysed masked. Participants were not masked. RESULTS:  50% (148/295) of participants in the intervention group responded to treatment compared with 43% (124/291) in the control group (adjusted odds ratio 1.3, 95% confidence interval 1.0 to 1.9; number needed to treat=13); a difference possibly due to chance (P=0.08). The intervention was associated with reductions in blood pressure (difference in mean systolic -2.7 mm Hg (95% confidence interval -4.7 to -0.6 mm Hg), mean diastolic -2.8 (-4.0 to -1.6 mm Hg); weight -1.0 kg (-1.8 to -0.3 kg), and body mass index -0.4 ( -0.6 to -0.1) but not cholesterol -0.1 (-0.2 to 0.0), smoking status (adjusted odds ratio 0.4, 0.2 to 1.0), or overall cardiovascular risk as a continuous measure (-0.4, -1.2 to 0.3)). The intervention was associated with improvements in diet, physical activity, drug adherence, and satisfaction with access to care, treatment received, and care coordination. One serious related adverse event occurred, when a participant was admitted to hospital with low blood pressure. CONCLUSIONS:  This evidence based telehealth approach was associated with small clinical benefits for a minority of people with high cardiovascular risk, and there was no overall improvement in average risk. The Healthlines service was, however, associated with improvements in some risk behaviours, and in perceptions of support and access to care.Trial registration Current Controlled Trials ISRCTN 27508731.

Effectiveness of an integrated telehealth service for patients with depression: a pragmatic randomised controlled trial of a complex intervention.

BACKGROUND: Many countries are exploring the potential of telehealth interventions to manage the rising number of people with chronic disorders. However, evidence of the effectiveness of telehealth is ambiguous. Based on an evidence-based conceptual framework, we developed an integrated telehealth service (the Healthlines Service) for chronic disorders and assessed its effectiveness in patients with depression. We aimed to compare the Healthlines Depression Service plus usual care with usual care alone. METHODS: This study was a pragmatic, multicentre, randomised controlled trial with participants recruited from 43 general practices in three areas of England. To be eligible, participants needed to have access to the internet and email, a Patient Health Questionnaire 9 (PHQ-9) score of at least 10, and a confirmed diagnosis of depression. Participants were individually assigned (1:1) to either the Healthlines Depression Service plus usual care or usual care alone. Random assignment was done by use of a web-based automated randomisation system, stratified by site and minimised by practice and PHQ-9 score. Participants were aware of their allocation, but outcomes were analysed masked. The Healthlines Service consisted of regular telephone calls from non-clinical, trained health advisers who followed standardised scripts generated by interactive software. After an initial assessment and goal-setting telephone call, the advisers called each participant on six occasions over 4 months, and then made up to three more calls at intervals of roughly 2 months to provide reinforcement and to detect relapse. Advisers supported participants in the use of online resources (including computerised cognitive behavioural therapy) and sought to encourage healthier lifestyles, optimise medication, and improve treatment adherence. The primary outcome was the proportion of participants responding to the intervention (defined as PHQ-9 <10 and reduction in PHQ-9 of ≥5 points) at 4 months after randomisation. The primary analysis was based on the intention-to-treat principle without imputation and all serious adverse events were investigated. This trial is registered with Current Controlled Trials, number ISRCTN 14172341. FINDINGS: Between July 24, 2012, and July 31, 2013, we recruited 609 participants, randomly assigning 307 to the Healthlines Service plus usual care and 302 to usual care. Primary outcome data were available for 525 (86%) participants. At 4 months, 68 (27%) of 255 individuals in the intervention group had a treatment response compared with 50 (19%) of 270 individuals in the usual care group (adjusted odds ratio 1·7, 95% CI 1·1-2·5, p=0·019). Compared with usual care alone, intervention participants reported improvements in anxiety, better access to support and advice, greater satisfaction with the support they received, and improvements in self-management and health literacy. During the trial, 70 adverse events were reported by participants, one of which was related to the intervention (increased anxiety from discussing depression) and was not serious. INTERPRETATION: This telehealth service based on non-clinically trained health advisers supporting patients in use of internet resources was both acceptable and effective compared with usual care. Our results provide support for the development and assessment of similar interventions in other chronic disorders to expand care provision. FUNDING: National Institute for Health Research (NIHR).

TElehealth in CHronic disease: mixed-methods study to develop the TECH conceptual model for intervention design and evaluation.

OBJECTIVE: To develop a conceptual model for effective use of telehealth in the management of chronic health conditions, and to use this to develop and evaluate an intervention for people with two exemplar conditions: raised cardiovascular disease risk and depression. DESIGN: The model was based on several strands of evidence: a metareview and realist synthesis of quantitative and qualitative evidence on telehealth for chronic conditions; a qualitative study of patients' and health professionals' experience of telehealth; a quantitative survey of patients' interest in using telehealth; and review of existing models of chronic condition management and evidence-based treatment guidelines. Based on these evidence strands, a model was developed and then refined at a stakeholder workshop. Then a telehealth intervention ('Healthlines') was designed by incorporating strategies to address each of the model components. The model also provided a framework for evaluation of this intervention within parallel randomised controlled trials in the two exemplar conditions, and the accompanying process evaluations and economic evaluations. SETTING: Primary care. RESULTS: The TElehealth in CHronic Disease (TECH) model proposes that attention to four components will offer interventions the best chance of success: (1) engagement of patients and health professionals, (2) effective chronic disease management (including subcomponents of self-management, optimisation of treatment, care coordination), (3) partnership between providers and (4) patient, social and health system context. Key intended outcomes are improved health, access to care, patient experience and cost-effective care. CONCLUSIONS: A conceptual model has been developed based on multiple sources of evidence which articulates how telehealth may best provide benefits for patients with chronic health conditions. It can be used to structure the design and evaluation of telehealth programmes which aim to be acceptable to patients and providers, and cost-effective.

Who uses NHS Direct? Investigating the impact of ethnicity on the uptake of telephone based healthcare.

INTRODUCTION: NHS Direct, a leading telephone healthcare provider worldwide, provided 24/7 health care advice and information to the public in England and Wales (1998-2014). The fundamental aim of this service was to increase accessibility, however, research has suggested a disparity in the utilisation of this service related to ethnicity. This research presents the first national study to determine how the diverse population in England have engaged with this service. METHODS: NHS Direct call data from the combined months of July, 2010 October, 2010, January 2011 and April, 2011 was analysed (N = 1,342, 245) for all 0845 4647 NHS Direct core service calls in England. Expected usage of NHS Direct was determined for each ethnic group of the population by age and gender and compared by actual usage using Chi-square analysis. A one-way analysis of variance (ANOVA) was used to determine variations of uptake by ethnic group and Index for Multiple Deprivation (IMD) 2010 rank. RESULTS: Results confirmed that all mixed ethnic groups (White and Black Caribbean, White and Black African, White and Asian) had a higher than expected uptake of NHS Direct which held consistent across all age groups. Lower than expected uptake was found for Black (African/Caribbean) and Asian (Bangladeshi/Indian/Chinese) ethnic group which held consistent by age and gender. For the Pakistani ethnic group usage was higher than expected in adults aged 40 years and older although was lower than expected in younger age groups (0-39). CONCLUSION: Findings support previous research suggesting a variation in usage of NHS Direct influenced by ethnicity, which is evidenced on a national level. Further research is now required to examine the underlying barriers that contribute to the ethnic variation in uptake of this service.

Barriers and facilitators to using NHS Direct: a qualitative study of 'users' and 'non-users'.

BACKGROUND: NHS Direct, introduced in 1998, has provided 24/7 telephone-based healthcare advice and information to the public in England and Wales. National studies have suggested variation in the uptake of this service amongst the UK's diverse population. This study provides the first exploration of the barriers and facilitators that impact upon the uptake of this service from the perspectives of both 'users' and 'non- users'. METHODS: Focus groups were held with NHS Direct 'users' (N = 2) from Bedfordshire alongside 'non-users' from Manchester (N = 3) and Mendip, Somerset (N = 4). Each focus group had between five to eight participants. A total of eighty one people aged between 21 and 94 years old (M: 58.90, SD: 22.70) took part in this research. Each focus group discussion lasted approximately 90 minutes and was audiotape-recorded with participants' permission. The recordings were transcribed verbatim. A framework approach was used to analyse the transcripts. RESULTS: The findings from this research uncovered a range of barriers and facilitators that impact upon the uptake of NHS Direct. 'Non-users' were unaware of the range of services that NHS Direct provided. Furthermore, 'non-users' highlighted a preference for face-to face communication, identifying a lack of confidence in discussing healthcare over the telephone. This was particularly evident among older people with cognitive difficulties. The cost to telephone a '0845' number from a mobile was also viewed to be a barrier to access NHS Direct, expressed more often by 'non-users' from deprived communities. NHS Direct 'users' identified that awareness, ease of use and convenience were facilitators which influenced their decision to use the service. CONCLUSIONS: An understanding of the barriers and facilitators which impact on the access and uptake of telephone-based healthcare is essential to move patients towards the self-care model. This research has highlighted the need for telephone-based healthcare services to increase public awareness; through the delivery of more targeted advertising to promote the service provision available.

Effectiveness and cost-effectiveness of a telehealth intervention to support the management of long-term conditions: study protocol for two linked randomized controlled trials.

BACKGROUND: As the population ages, more people are suffering from long-term health conditions (LTCs). Health services around the world are exploring new ways of supporting people with LTCs and there is great interest in the use of telehealth: technologies such as the Internet, telephone and home self-monitoring. METHODS/DESIGN: This study aims to evaluate the effectiveness and cost-effectiveness of a telehealth intervention delivered by NHS Direct to support patients with LTCs. Two randomized controlled trials will be conducted in parallel, recruiting patients with two exemplar LTCs: depression or raised cardiovascular disease (CVD) risk. A total of 1,200 patients will be recruited from approximately 42 general practices near Bristol, Sheffield and Southampton, UK. Participants will be randomly allocated to either usual care (control group) or usual care plus the NHS Direct Healthlines Service (intervention group). The intervention is based on a conceptual model incorporating promotion of self-management, optimisation of treatment, coordination of care and engagement of patients and general practitioners. Participants will be provided with tailored help, combining telephone advice from health information advisors with support to use a range of online resources. Participants will access the service for 12 months. Outcomes will be collected at baseline, four, eight and 12 months for the depression trial and baseline, six and 12 months for the CVD risk trial. The primary outcome will be the proportion of patients responding to treatment, defined in the depression trial as a PHQ-9 score <10 and an absolute reduction in PHQ-9 ≥5 after 4 months, and in the CVD risk trial as maintenance or reduction of 10-year CVD risk after 12 months. The study will also assess whether the intervention is cost-effective from the perspective of the NHS and personal social services. An embedded qualitative interview study will explore healthcare professionals' and patients' views of the intervention. DISCUSSION: This study evaluates a complex telehealth intervention which combines evidence-based components and is delivered by an established healthcare organisation. The study will also analyse health economic information. In doing so, the study hopes to address some of the limitations of previous research by demonstrating the effectiveness and cost-effectiveness of a real world telehealth intervention. TRIAL REGISTRATION: Current Controlled Trials: Depression trial ISRCTN14172341 and cardiovascular disease risk trial ISRCTN27508731.

A cost-minimisation study of 1,001 NHS Direct users.

BACKGROUND: To determine financial and quality of life impact of patients calling the '0845' NHS Direct (NHS Direct) telephone helpline from the perspective of NHS service providers. METHODS: Cost-minimisation of repeated cohort measures from a National Survey of NHS Direct's telephone service using telephone survey results. 1,001 people contacting NHS Direct's 0845 telephone service in 2009 who agreed to a 4-6 week follow-up. A cost comparison between NHS Direct recommendation and patient-stated first alternative had NHS Direct not been available. Analysis also considers impact on quality of life of NHS Direct recommendations using the Visual Analogue Scale of the EQ-5D. RESULTS: Significant referral pattern differences were observed between NHS Direct recommendation and patient-stated first alternatives (p < 0.001). Per patient cost savings resulted from NHS Direct's recommendation to attend A&E (£36.54); GP Practice (£19.41); Walk-In Centre (£49.85); Pharmacist (£25.80); Dentist (£2.35) and do nothing/treat at home (£19.77), while it was marginally more costly for 999 calls (£3.33). Overall an average per patient saving of £19.55 was found (a 36% saving compared with patient-stated first alternatives). For 5 million NHS Direct telephone calls per year, this represents an annual cost saving of £97,756,013. Significant quality of life differences were observed at baseline and follow-up between those who believed their problem was 'urgent' (p = 0.001) and those who said it was 'non-urgent' (p = 0.045). Whilst both groups improved, self-classified 'urgent' cases made greater health gains than those who said they were 'non-urgent' (urgent by 21.5 points; non-urgent by 16.1 points). CONCLUSIONS: The '0845' service of NHS Direct produced substantial cost savings in terms of referrals to the other parts of the NHS when compared with patients' own stated first alternative. Health-related quality of life also improved for users of this service demonstrating that these savings can be produced without perceived harm to patients.

Virological self-sampling to monitor influenza antiviral susceptibility in a community cohort.

OBJECTIVE: To perform antiviral susceptibility monitoring of treated individuals in the community during the 2009 influenza A(H1N1) pandemic in England. PATIENTS AND METHODS: Between 200 and 400 patients were enrolled daily through the National Pandemic Flu Service (NPFS) and issued with a self-sampling kit. Initially, only persons aged 16 and over were eligible, but from 12 November (week 45), self-sampling was extended to include school-age children (5 years and older). All samples received were screened for influenza A(H1N1)pdm09 as well as seasonal influenza [A(H1N1), A(H3N2) and influenza B] by a combination of RT-PCR and virus isolation methods. Influenza A(H1N1)pdm09 RT-PCR-positive samples were screened for the oseltamivir resistance-inducing H275Y substitution, and a subset of samples also underwent phenotypic antiviral susceptibility testing by enzyme inhibition assay. RESULTS: We were able to detect virus by RT-PCR in self-taken samples and recovered infectious virus enabling further virological characterization. The majority of influenza A(H1N1)pdm09 RT-PCR-positive NPFS samples (n = 1273) were taken after oseltamivir treatment had begun. No reduction in phenotypic susceptibility to neuraminidase inhibitors was detected, but five cases with minority quasi-species of oseltamivir-resistant virus (an H275Y amino acid substitution in neuraminidase) were detected. CONCLUSIONS: Self-sampling is a useful tool for community surveillance, particularly for the follow-up of drug-treated patients. The virological study of self-taken samples from the NPFS provided a unique opportunity to evaluate the emergence of oseltamivir resistance in treated individuals with mild illness in the community, a target population that may not be captured by traditional sentinel surveillance schemes.

The association of geographical location and neighbourhood deprivation with older people's use of NHS Direct: a population-based study.

BACKGROUND: no research has investigated how older people's use of NHS Direct, the 24-h telephone health advice and information service in England and Wales, varies according to geographical location and deprivation. OBJECTIVES: to describe the geographic pattern of older people's use of NHS Direct and examine the relationship between service use and deprivation. DESIGN: descriptive, exploratory, cross-sectional, population-based study. SETTING: calls to all 32-NHS Direct contact centres in England/Wales. PARTICIPANTS: people aged 65 years and above who used NHS Direct between 1 December 2007 and 30 November 2008. RESULTS: differences in older people's use of NHS Direct were observed in England and Wales. In England, the call rate was highest in Yorkshire and the Humber and was lowest in the West Midlands. At the postcode level, the rate of calls ranged from 0.167 (Blackburn) to 0.011 (Carlisle) per person per annum. In England, but not in Wales, the level of deprivation was associated with the rate of calls, older people living in the most deprived areas had the highest rate of calls to NHS Direct. CONCLUSIONS: the results are useful for future planning to meet the needs of older people, and in informing national policies for the development of NHS Direct.

A U.K. case study of who uses NHS direct: investigating the impact of age, gender, and deprivation on the utilization of NHS direct.

OBJECTIVES: National Health Service (NHS) Direct provides a 24/7 telephone-based healthcare advice and information service to the public in England. Locally based studies have suggested variation in the uptake of this service among the United Kingdom's diverse population. This study seeks to examine this issue at a national level. SUBJECTS AND METHODS: One month's period of national data was collected (July 2010) from the NHS Direct Clinical Assessment System for all 0845 4647 calls in England. Calls were matched to place of residence and were analyzed for age, gender, and deprivation using negative binominal regression. RESULTS: Within the context of NHS Direct the pattern of calls was highest for children 5 years old and under, with lowest call rates found for males and older people (65+ years old). Furthermore, call rates were lowest in the most deprived areas for children (0-15 years old). Gender differences were noted, whereby male call rates were higher in the most deprived areas for all age groups. Furthermore, call rates for or on behalf of older females (60+ years old) were lower in areas of extreme deprivation. CONCLUSIONS: The findings suggest there is variation in usage of NHS Direct. Such usage appears to be influenced by age, gender, and deprivation. Further research is required to examine the underlying factors that contribute to variation in uptake of these services. This will enable the development of future promotional campaigns that can target particular sections of the population to encourage use of telephone-based health services.

Older people's use of NHS Direct.

INTRODUCTION: the 24 h telephone health information and advice service in England and Wales, NHS Direct, aims to help callers manage health problems and relieve pressure on primary healthcare services. Although older people may use NHS Direct less than other age groups, no research has specifically investigated older people's use of the service. AIMS: the aim of this study was to describe the older people's use of NHS Direct and to explore differences in the use of NHS Direct among subgroups of older people. METHODS: a cross-sectional exploratory descriptive design utilising quantitative methods was adopted. Data on all calls made to NHS Direct by, or on behalf of, people aged 65 and over between 1 December 2007 and 30 November 2008 were analysed. RESULTS: a total of 402,959 telephone calls were made to NHS-Direct regarding older people during the 12-month study period. The call rate was higher among women and in older age groups. Most calls were regarding actual symptoms, e.g. pain, digestive problems. CONCLUSIONS: this research identifies the characteristics of calls made to NHS Direct relating to older people and how they use the service. This will help with the planning and development of services to meet the needs of the older population.

The characteristics and motivations of online health information seekers: cross-sectional survey and qualitative interview study.

BACKGROUND: Most households in the United Kingdom have Internet access, and health-related Internet use is increasing. The National Health Service (NHS) Direct website is the major UK provider of online health information. OBJECTIVE: Our objective was to identify the characteristics and motivations of online health information seekers accessing the NHS Direct website, and to examine the benefits and challenges of the health Internet. METHODS: We undertook an online questionnaire survey, offered to users of the NHS Direct website. A subsample of survey respondents participated in in-depth, semistructured, qualitative interviews by telephone or instant messaging/email. Questionnaire results were analyzed using chi-square statistics. Thematic coding with constant comparison was used for interview transcript analysis. RESULTS: In total 792 respondents completed some or all of the survey: 71.2% (534/750 with data available) were aged under 45 years, 67.4% (511/758) were female, and 37.7% (286/759) had university-level qualifications. They sought information for themselves (545/781, 69.8%), someone else (172/781, 22.0%), or both (64/781, 8.2%). Women were more likely than men to seek help for someone else or both themselves and someone else (168/509 vs 61/242, χ(2) (2) = 6.35, P = .04). Prior consultation with a health professional was reported by 44.9% (346/770), although this was less common in younger age groups (<36 years) (χ(2) (1) = 24.22, P < .001). Participants aged 16 to 75 years (n = 26, 20 female, 6 male) were recruited for interview by telephone (n = 23) and instant messaging/email (n = 3). Four major interview themes were identified: motivations for seeking help online; benefits of seeking help in this way and some of the challenges faced; strategies employed in navigating online health information provision and determining what information to use and to trust; and specific comments regarding the NHS Direct website service. Within the motivation category, four concepts emerged: the desire for reassurance; the desire for a second opinion to challenge other information; the desire for greater understanding to supplement other information; and perceived external barriers to accessing information through traditional sources. The benefits clustered around three theme areas: convenience, coverage, and anonymity. Various challenges were discussed but no prominent theme emerged. Navigating online health information and determining what to trust was regarded as a "common sense" activity, and brand recognition was important. Specific comments about NHS Direct included the perception that the online service was integrated with traditional service provision. CONCLUSIONS: This study supports a model of evolutionary rather than revolutionary change in online health information use. Given increasing resource constraints, the health care community needs to seek ways of promoting efficient and appropriate health service use, and should aim to harness the potential benefits of the Internet, informed by an understanding of how and why people go online for health.

Reassuring and managing patients with concerns about swine flu: qualitative interviews with callers to NHS Direct.

BACKGROUND: During the early stages of the 2009 swine flu (influenza H1N1) outbreak, the large majority of patients who contacted the health services about the illness did not have it. In the UK, the NHS Direct telephone service was used by many of these patients. We used qualitative interviews to identify the main reasons why people approached NHS Direct with concerns about swine flu and to identify aspects of their contact which were reassuring, using a framework approach. METHODS: 33 patients participated in semi-structured interviews. All patients had telephoned NHS Direct between 11 and 14 May with concerns about swine flu and had been assessed as being unlikely to have the illness. RESULTS: Reasons for seeking advice about swine flu included: the presence of unexpectedly severe flu-like symptoms; uncertainties about how one can catch swine flu; concern about giving it to others; pressure from friends or employers; and seeking 'peace of mind.' Most participants found speaking to NHS Direct reassuring or useful. Helpful aspects included: having swine flu ruled out; receiving an alternative explanation for symptoms; clarification on how swine flu is transmitted; and the perceived credibility of NHS Direct. No-one reported anything that had increased their anxiety and only one participant subsequently sought additional advice about swine flu from elsewhere. CONCLUSIONS: Future major incidents involving other forms of chemical, biological or radiological hazards may also cause large numbers of unexposed people to seek health advice. Our data suggest that providing telephone triage and information is helpful in such instances, particularly where advice can be given via a trusted, pre-existing service.

Tracking the spatial diffusion of influenza and norovirus using telehealth data: a spatiotemporal analysis of syndromic data.

BACKGROUND: Telehealth systems have a large potential for informing public health authorities in an early stage of outbreaks of communicable disease. Influenza and norovirus are common viruses that cause significant respiratory and gastrointestinal disease worldwide. Data about these viruses are not routinely mapped for surveillance purposes in the UK, so the spatial diffusion of national outbreaks and epidemics is not known as such incidents occur. We aim to describe the geographical origin and diffusion of rises in fever and vomiting calls to a national telehealth system, and consider the usefulness of these findings for influenza and norovirus surveillance. METHODS: Data about fever calls (5- to 14-year-old age group) and vomiting calls (> or = 5-year-old age group) in school-age children, proxies for influenza and norovirus, respectively, were extracted from the NHS Direct national telehealth database for the period June 2005 to May 2006. The SaTScan space-time permutation model was used to retrospectively detect statistically significant clusters of calls on a week-by-week basis. These syndromic results were validated against existing laboratory and clinical surveillance data. RESULTS: We identified two distinct periods of elevated fever calls. The first originated in the North-West of England during November 2005 and spread in a south-east direction, the second began in Central England during January 2006 and moved southwards. The timing, geographical location, and age structure of these rises in fever calls were similar to a national influenza B outbreak that occurred during winter 2005-2006. We also identified significantly elevated levels of vomiting calls in South-East England during winter 2005-2006. CONCLUSION: Spatiotemporal analyses of telehealth data, specifically fever calls, provided a timely and unique description of the evolution of a national influenza outbreak. In a similar way the tool may be useful for tracking norovirus, although the lack of consistent comparison data makes this more difficult to assess. In interpreting these results, care must be taken to consider other infectious and non-infectious causes of fever and vomiting. The scan statistic should be considered for spatial analyses of telehealth data elsewhere and will be used to initiate prospective geographical surveillance of influenza in England.