RESUMO
Paediatric emergency department (PED) attendances reduced worldwide during the COVID-19 pandemic (2020) but anecdotally babies under 30 days (BUD) appeared less affected. We collated monthly PED attendances (16 years and under) across four hospitals (three district general hospitals and a tertiary specialist PED) in England, UK from January 2017 to December 2020. Gross PED attendances dropped by 34% in 2020 (n=98 256) compared to 2019 (n=148 640). However, cumulative BUD attendances dropped by only 6% in 2020 (n=3922) compared to 2019 (n=4162). Monthly site-specific attendances showed marginal variation. PED attendances broadly decreased in 2020 with less of an impact on BUD.
Assuntos
COVID-19 , COVID-19/epidemiologia , Criança , Serviço Hospitalar de Emergência , Hospitais , Humanos , Lactente , Pandemias , Estudos RetrospectivosRESUMO
BACKGROUND: During pandemics of novel influenza and outbreaks of emerging infections, surge in health-care demand can exceed capacity to provide normal standards of care. In such exceptional circumstances, triage tools may aid decisions in identifying people who are most likely to benefit from higher levels of care. Rapid research during the early phase of an outbreak should allow refinement and validation of triage tools so that in the event of surge a valid tool is available. The overarching study aim is to conduct a prospective near real-time analysis of structured clinical assessments of influenza-like illness (ILI) using primary care electronic health records (EHRs) during a pandemic. This abstract summarises the preparatory work, infrastructure development, user testing and proof-of-concept study. OBJECTIVES: (1) In preparation for conducting rapid research in the early phase of a future outbreak, to develop processes that allow near real-time analysis of general practitioner (GP) assessments of people presenting with ILI, management decisions and patient outcomes. (2) As proof of concept: conduct a pilot study evaluating the performance of the triage tools 'Community Assessment Tools' and 'Pandemic Medical Early Warning Score' to predict hospital admission and death in patients presenting with ILI to GPs during inter-pandemic winter seasons. DESIGN: Prospective near real-time analysis of structured clinical assessments and anonymised linkage to data from EHRs. User experience was evaluated by semistructured interviews with participating GPs. SETTING: Thirty GPs in England, Wales and Scotland, participating in the Clinical Practice Research Datalink. PARTICIPANTS: All people presenting with ILI. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Study outcome is proof of concept through demonstration of data capture and near real-time analysis. Primary patient outcomes were hospital admission within 24 hours and death (all causes) within 30 days of GP assessment. Secondary patient outcomes included GP decision to prescribe antibiotics and/or influenza-specific antiviral drugs and/or refer to hospital - if admitted, the need for higher levels of care and length of hospital stay. DATA SOURCES: Linked anonymised data from a web-based structured clinical assessment and primary care EHRs. RESULTS: In the 24 months to April 2015, data from 704 adult and 159 child consultations by 30 GPs were captured. GPs referred 11 (1.6%) adults and six (3.8%) children to hospital. There were 13 (1.8%) deaths of adults and two (1.3%) of children. There were too few outcome events to draw any conclusions regarding the performance of the triage tools. GP interviews showed that although there were some difficulties with installation, the web-based data collection tool was quick and easy to use. Some GPs felt that a minimal monetary incentive would promote participation. CONCLUSIONS: We have developed processes that allow capture and near real-time automated analysis of GP's clinical assessments and management decisions of people presenting with ILI. FUTURE WORK: We will develop processes to include other EHR systems, attempt linkage to data on influenza surveillance and maintain processes in readiness for a future outbreak. STUDY REGISTRATION: This study is registered as ISRCTN87130712 and UK Clinical Research Network 12827. FUNDING: The National Institute for Health Research Health Technology Assessment programme. MGS is supported by the UK NIHR Health Protection Research Unit in Emerging and Zoonotic Infections.
Assuntos
Registros Eletrônicos de Saúde , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Pandemias , Triagem/métodos , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Protocolos Clínicos , Anonimização de Dados , Registros Eletrônicos de Saúde/organização & administração , Feminino , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/mortalidade , Influenza Humana/transmissão , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Atenção Primária à Saúde , Estudos Prospectivos , Reino Unido/epidemiologia , Zoonoses/epidemiologiaAssuntos
Anticoagulantes/administração & dosagem , Fibrilação Atrial/tratamento farmacológico , Registros Eletrônicos de Saúde , Hemorragias Intracranianas/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Tromboembolia/tratamento farmacológico , Trombose/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Comorbidade , Inglaterra/epidemiologia , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Hemorragias Intracranianas/classificação , Hemorragias Intracranianas/epidemiologia , Masculino , Pessoa de Meia-Idade , Escócia/epidemiologia , Acidente Vascular Cerebral/classificação , Acidente Vascular Cerebral/epidemiologia , Inquéritos e Questionários , Tromboembolia/diagnóstico , Tromboembolia/epidemiologia , Trombose/diagnóstico , Trombose/epidemiologiaRESUMO
OBJECTIVES: Overutilisation of antibiotics may contribute to the emergence of antimicrobial drug resistance, a growing international concern. This study aimed to analyse the performance of UK general practices with respect to antibiotic prescribing for respiratory tract infections (RTIs) among young and middle-aged adults. SETTING: Data are reported for 568 UK general practices contributing to the Clinical Practice Research Datalink. PARTICIPANTS: Participants were adults aged 18-59 years. Consultations were identified for acute upper RTIs including colds, cough, otitis-media, rhino-sinusitis and sore throat. PRIMARY AND SECONDARY OUTCOME MEASURES: For each consultation, we identified whether an antibiotic was prescribed. The proportion of RTI consultations with antibiotics prescribed was estimated. RESULTS: There were 568 general practices analysed. The median general practice prescribed antibiotics at 54% of RTI consultations. At the highest prescribing 10% of practices, antibiotics were prescribed at 69% of RTI consultations. At the lowest prescribing 10% of practices, antibiotics were prescribed at 39% RTI consultations. The median practice prescribed antibiotics at 38% of consultations for 'colds and upper RTIs', 48% for 'cough and bronchitis', 60% for 'sore throat', 60% for 'otitis-media' and 91% for 'rhino-sinusitis'. The highest prescribing 10% of practices issued antibiotic prescriptions at 72% of consultations for 'colds', 67% for 'cough', 78% for 'sore throat', 90% for 'otitis-media' and 100% for 'rhino-sinusitis'. CONCLUSIONS: Most UK general practices prescribe antibiotics to young and middle-aged adults with respiratory infections at rates that are considerably in excess of what is clinically justified. This will fuel antibiotic resistance.
Assuntos
Antibacterianos/uso terapêutico , Medicina Geral , Prescrição Inadequada/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Infecções Respiratórias/tratamento farmacológico , Adolescente , Adulto , Resfriado Comum/tratamento farmacológico , Tosse/tratamento farmacológico , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Otite Média/tratamento farmacológico , Faringite/tratamento farmacológico , Estudos Retrospectivos , Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Reino Unido , Adulto JovemRESUMO
PURPOSE: This study aimed to implement a point-of-care cluster randomized trial using electronic health records. We evaluated the effectiveness of electronically delivered decision support tools at reducing antibiotic prescribing for respiratory tract infections in primary care. METHODS: Family practices from England and Scotland participating in the Clinical Practice Research Datalink (CPRD) were included in the trial; 53 family practices were allocated to intervention and 51 practices were allocated to usual care. Patients aged 18 to 59 years consulting for respiratory tract infections were eligible. The intervention was through remotely installed, computer-delivered decision support tools accessed during the consultations. Control practices provided usual care. The primary outcome was the proportion of consultations for respiratory tract infections with an antibiotic prescribed based on electronic health records. Family practice-specific proportions were included in a cluster-level analysis. RESULTS: Data were analyzed for 603,409 patients: 317,717 at intervention practices and 285,692 at control practices. Use of the intervention was less than anticipated, varying among practices. There was a reduction in proportion of consultations with antibiotics prescribed of 1.85% (95% CI, 0.10%-3.59%, P=.038) and in the rate of antibiotic prescribing for respiratory tract infections (9.69%; 95% CI, 0.75%-18.63%, fewer prescriptions per 1,000 patient-years, P=.034). There were no adverse events. CONCLUSIONS: Cluster randomized trials may be implemented efficiently in large samples from routine care settings by using primary care electronic health records. Future studies should develop and test multicomponent methods for remotely delivered intervention.
Assuntos
Antibacterianos/uso terapêutico , Técnicas de Apoio para a Decisão , Registros Eletrônicos de Saúde/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Atenção Primária à Saúde/métodos , Infecções Respiratórias/tratamento farmacológico , Adolescente , Adulto , Análise por Conglomerados , Inglaterra , Medicina de Família e Comunidade/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escócia , Adulto JovemRESUMO
BACKGROUND: Pragmatic trials compare the effects of different decisions in usual clinical practice. OBJECTIVES: To develop and evaluate methods to implement simple pragmatic trials using routinely collected electronic health records (EHRs) and recruiting patients at the point of care; to identify the barriers and facilitators for general practitioners (GPs) and patients and the experiences of trial participants. DESIGN: Two exemplar randomised trials (Retropro and eLung) with qualitative evaluations. SETTING: Four hundred and fifty-nine English and Scottish general practices contributing EHRs to a research database, of which 17 participated in the trials. PARTICIPANTS: Retropro aimed to recruit 300 patients with hypercholesterolaemia and high cardiovascular risk and eLung aimed to recruit 150 patients with a chronic obstructive pulmonary disease exacerbation. INTERVENTIONS: Retropro randomised between simvastatin and atorvastatin and eLung between immediate antibiotics and deferred or non-use. eLung recruited during an unscheduled consultation using EHR flagging. MAIN OUTCOME MEASURE: Successful trial completion with implementation of information technology (IT) system for flagging and data processing and documentation of operational and scientific experiences. DATA SOURCES: EHR research database. RESULTS: The governance approval process took over 3 years. A total of 58.8% of the practices (n = 270) expressed interest in participating. The number of interested practices dropped substantially with each stage of the governance process. In Retropro, 6.5% of the practices (n = 30) were eventually approved and 3.7% (n = 17) recruited patients; in eLung, these numbers were 6.8% (n = 31) and 1.3% (n = 6) respectively. Retropro successfully completed recruitment (301 patients) whereas eLung recruited 31 patients. Retropro recruited 20.6% of all statin starters in recruiting practices and 1.1% in the EHR database; the comparable numbers for eLung were 32.3% and 0.9% respectively. The IT system allowed for complex eligibility criteria with central on and off control of recruitment and flagging at a practice. Good Clinical Practice guidelines, governance and consent procedures were found to have substantially affected the intended simple nature of the trials. One qualitative study of 13 clinicians found that clinicians were generally positive about the principle of computerised trial recruitment (flagging during consultation). However, trials which did not include patients with acute illness were favoured. The second qualitative process evaluation interviewed 27 GPs about their actual experiences, including declining, recruiting and non-recruiting GPs. Opportunistic patient recruitment during a routine GP consultation was found to be the most controversial element. The actual experiences of recruiting patients during unscheduled consultation were generally more positive than the hypothetical views of GPs. Several of the recruiting GPs reported the process took 5 minutes and was straightforward and feasible on most occasions. Almost all GPs expressed their strong support for the use of EHRs for trials. Ten eLung participants were interviewed, all of whom considered it acceptable to be recruited during a consultation and to use EHRs for trials. CONCLUSIONS: EHR point-of-care trials are feasible, although the recruitment of clinicians is a major challenge owing to the complexity of trial approvals. These trials will provide substantial evidence on clinical effectiveness only if trial interventions and participating clinicians and patients are typical of usual clinical care and trials are simple to initiate and conduct. Recommendations for research include the development of evidence and implementation of risk proportionality in trial governance and conduct. TRIAL REGISTRATION: Current Controlled Trials ISRCTN33113202 and ISRCTN72035428. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and the Wellcome Trust and will be published in full in Health Technology Assessment; Vol. 18, No. 43. See the NIHR Journals Library website for further project information.
Assuntos
Registros Eletrônicos de Saúde , Seleção de Pacientes , Ensaios Clínicos Pragmáticos como Assunto/métodos , Adulto , Assistência Ambulatorial , Anticolesterolemiantes/uso terapêutico , Atorvastatina , Bases de Dados Factuais , Estudos de Avaliação como Assunto , Estudos de Viabilidade , Feminino , Clínicos Gerais , Ácidos Heptanoicos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Pirróis/uso terapêutico , Sinvastatina/uso terapêuticoRESUMO
BACKGROUND AND PURPOSE: The aim of this study was to evaluate whether the remote introduction of electronic decision support tools into family practices improves risk factor control after first stroke. This study also aimed to develop methods to implement cluster randomized trials in stroke using electronic health records. METHODS: Family practices were recruited from the UK Clinical Practice Research Datalink and allocated to intervention and control trial arms by minimization. Remotely installed, electronic decision support tools promoted intensified secondary prevention for 12 months with last measure of systolic blood pressure as the primary outcome. Outcome data from electronic health records were analyzed using marginal models. RESULTS: There were 106 Clinical Practice Research Datalink family practices allocated (intervention, 53; control, 53), with 11 391 (control, 5516; intervention, 5875) participants with acute stroke ever diagnosed. Participants at trial practices had similar characteristics as 47,887 patients with stroke at nontrial practices. During the intervention period, blood pressure values were recorded in the electronic health records for 90% and cholesterol values for 84% of participants. After intervention, the latest mean systolic blood pressure was 131.7 (SD, 16.8) mm Hg in the control trial arm and 131.4 (16.7) mm Hg in the intervention trial arm, and adjusted mean difference was -0.56 mm Hg (95% confidence interval, -1.38 to 0.26; P=0.183). The financial cost of the trial was approximately US $22 per participant, or US $2400 per family practice allocated. CONCLUSIONS: Large pragmatic intervention studies may be implemented at low cost by using electronic health records. The intervention used in this trial was not found to be effective, and further research is needed to develop more effective intervention strategies. CLINICAL TRIAL REGISTRATION URL: http://www.controlled-trials.com. Current Controlled Trials identifier: ISRCTN35701810.
Assuntos
Registros Eletrônicos de Saúde , Avaliação de Resultados em Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Registros Eletrônicos de Saúde/estatística & dados numéricos , Medicina de Família e Comunidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Reino UnidoRESUMO
BACKGROUND: There is growing interest in conducting clinical and cluster randomized trials through electronic health records. This paper reports on the methodological issues identified during the implementation of two cluster randomized trials using the electronic health records of the Clinical Practice Research Datalink (CPRD). METHODS: Two trials were completed in primary care: one aimed to reduce inappropriate antibiotic prescribing for acute respiratory infection; the other aimed to increase physician adherence with secondary prevention interventions after first stroke. The paper draws on documentary records and trial datasets to report on the methodological experience with respect to research ethics and research governance approval, general practice recruitment and allocation, sample size calculation and power, intervention implementation, and trial analysis. RESULTS: We obtained research governance approvals from more than 150 primary care organizations in England, Wales, and Scotland. There were 104 CPRD general practices recruited to the antibiotic trial and 106 to the stroke trial, with the target number of practices being recruited within six months. Interventions were installed into practice information systems remotely over the internet. The mean number of participants per practice was 5,588 in the antibiotic trial and 110 in the stroke trial, with the coefficient of variation of practice sizes being 0.53 and 0.56 respectively. Outcome measures showed substantial correlations between the 12 months before, and after intervention, with coefficients ranging from 0.42 for diastolic blood pressure to 0.91 for proportion of consultations with antibiotics prescribed, defining practice and participant eligibility for analysis requires careful consideration. CONCLUSIONS: Cluster randomized trials may be performed efficiently in large samples from UK general practices using the electronic health records of a primary care database. The geographical dispersal of trial sites presents a difficulty for research governance approval and intervention implementation. Pretrial data analyses should inform trial design and analysis plans. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 47558792 and ISRCTN 35701810 (both registered on 17 March 2010).
Assuntos
Antibacterianos/uso terapêutico , Registros Eletrônicos de Saúde , Padrões de Prática Médica , Atenção Primária à Saúde/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Infecções Respiratórias/tratamento farmacológico , Governança Clínica , Análise por Conglomerados , Técnicas de Apoio para a Decisão , Humanos , Projetos de Pesquisa , Reino UnidoRESUMO
AIMS: Electronic healthcare records (EHRs) are increasingly used to store clinical information. A secondary benefit of EHRs is their use, in an anonymized form, for observational research. The Clinical Practice Research Datalink (CPRD) contains EHRs from primary care in the UK and, despite 1083 peer-reviewed research publications, has never been used to obtain pharmacogenetic samples. Using a statin-induced myopathy paradigm, we evaluated using the CPRD to obtain patient samples for a pharmacogenetic study targeting 250 cases and 500 controls from UK general practitioner (GP) practices. METHODS: The CPRD identified potential patients fitting specific case-definition criteria (active rhabdomyolysis or creatine phosphokinase > four times the upper limit of normal), and corresponding GP practices were asked to invite patient participation. Consenting patients were requested to provide either saliva or blood samples and to complete an ethnicity questionnaire. Control subjects were recruited from the same GP practice (saliva) or a small number of practices (blood). Samples were forwarded for DNA extraction. RESULTS: Thirty-six months of recruitment yielded DNA samples from 149 statin-induced myopathy cases and 587 tolerant controls. Data show that contacting patients through their GP is a reliable method for obtaining samples without compromising anonymity. Saliva collection directly from patients was considerably less effective than blood sampling. After 10 months of recruitment, saliva sampling was suspended in favour of blood sampling. CONCLUSIONS: We demonstrate the potential of EHRs for identifying accurately phenotyped cases and controls for pharmacogenetic studies. Recruitment was successful only because of the willingness of GP practices to participate and the existence of strong doctor-patient relationships. The present study provides a model that can be implemented in future genetic analyses using EHRs.
Assuntos
Registros Eletrônicos de Saúde , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Doenças Musculares/induzido quimicamente , Manejo de Espécimes , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SalivaRESUMO
BACKGROUND: The study aimed to conduct a process evaluation for a cluster randomised trial of a computer-delivered, point-of-care intervention to reduce antibiotic prescribing in primary care. The study aimed to evaluate both the intervention and implementation of the trial. METHODS: The intervention comprised a set of electronic educational and decision support tools that were remotely installed and activated during consultations with patients with acute respiratory infections over a 12 month intervention period. A mixed method evaluation was conducted with 103 general practitioners (GPs) who participated in the trial. Semi-structured telephone interviews were conducted with 20 GPs who had been in the intervention group of the trial and 4 members of the implementation staff. Questionnaires, consisting of both intervention evaluation and theory-based measures, were self-administered to 83 GPs (56 control group and 27 intervention group). RESULTS: Interviews suggested that a key factor influencing GPs' use of the intervention appeared to be their awareness of the implementation of the system into their practice. GPs who were aware of the implementation of the intervention reported feeling confident in using it if they chose to and understood the purpose of the intervention screens. However, GPs who were unaware that the intervention would be appearing often reported feeling confused when they saw the messages appear on the screen and not fully understanding what they were for or how they could be used. Intervention evaluation questionnaires indicated that GPs were satisfied with the usability of the prompts, and theory-based measures revealed that intervention group GPs reported higher levels of self-efficacy in managing RTI patients according to recommended guidelines compared to GPs in the control group. CONCLUSIONS: Remote installation of a computer-delivered intervention for use at the point-of-care was feasible and acceptable. Additional measures to promote awareness of the intervention may be required to promote health care professionals' utilisation of the intervention and these might sometimes compromise the pragmatic intention of a trial. TRIAL REGISTRATION: ISRCTN47558792 (registered on 17 March 2010).
Assuntos
Antibacterianos/uso terapêutico , Tomada de Decisões Assistida por Computador , Clínicos Gerais , Uso Excessivo de Medicamentos Prescritos/prevenção & controle , Infecções Respiratórias/tratamento farmacológico , Adulto , Idoso , Quimioterapia Assistida por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito/normas , Gravidez , Atenção Primária à Saúde/normas , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The purpose of this research is to develop and evaluate methods for conducting pragmatic cluster randomized trials in a primary care electronic database. The proposal describes one application, in a less frequent chronic condition of public health importance, secondary prevention of stroke. A related protocol in antibiotic prescribing was reported previously. METHODS/DESIGN: The study aims to implement a cluster randomized trial (CRT) using the electronic patient records of the General Practice Research Database (GPRD) as a sampling frame and data source. The specific objective of the trial is to evaluate the effectiveness of a computer-delivered intervention at enhancing the delivery of stroke secondary prevention in primary care. GPRD family practices will be allocated to the intervention or usual care. The intervention promotes the use of electronic prompts to support adherence with the recommendations of the UK Intercollegiate Stroke Working Party and NICE guidelines for the secondary prevention of stroke in primary care. Primary outcome measure will be the difference in systolic blood pressure between intervention and control trial arms at 12-month follow-up. Secondary outcomes will be differences in serum cholesterol, prescribing of antihypertensive drugs, statins, and antiplatelet therapy. The intervention will continue for 12 months. Information on the utilization of the decision-support tools will also be analyzed. DISCUSSION: The CRT will investigate the effectiveness of using a computer-delivered intervention to reduce the risk of stroke recurrence following a first stroke event. The study will provide methodological guidance on the implementation of CRTs in electronic databases in primary care. TRIAL REGISTRATION: Current Controlled Trials ISRCTN35701810.
Assuntos
Bases de Dados Factuais , Medicina Geral , Padrões de Prática Médica , Atenção Primária à Saúde , Sistemas de Alerta , Projetos de Pesquisa , Prevenção Secundária/métodos , Acidente Vascular Cerebral/terapia , Registros Eletrônicos de Saúde , Medicina Geral/normas , Fidelidade a Diretrizes , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Atenção Primária à Saúde/normas , Prevenção Secundária/normas , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/prevenção & controle , Resultado do Tratamento , Reino UnidoRESUMO
BACKGROUND: The purpose of this research is to develop and evaluate methods for conducting cluster randomised trials in a primary care database that contains electronic patient records for large numbers of family practices. Cluster randomised trials are trials in which the units allocated represent groups of individuals, in this case family practices and their registered patients. Cluster randomised trials often suffer from the limitation that they include too few clusters, leading to problems of insufficient power and only imprecise estimation of the intraclass correlation coefficient, a key design parameter. This difficulty might be overcome by utilising databases that already hold electronic patient records for large numbers of practices. The protocol describes one application: a study of antibiotic prescribing for acute respiratory infection; a second protocol outlines an intervention in a less frequent chronic condition of public health importance, stroke. METHODS/DESIGN: The objective of the study is to implement a cluster randomised trial to test the effectiveness of an electronic record-based intervention at achieving a reduction in antibiotic prescribing at consultations for respiratory illness in patients aged 18 and 59 years old in intervention family practices as compared with controls. Family practices will be recruited from the practices that presently contribute data to the UK General Practice Research Database (GPRD). Following randomisation, electronic prompts will be installed remotely at intervention practices to promote adherence with evidence-based standards of medical practice. The intervention was developed through qualitative research at non-intervention practices. Data for outcome assessment will be obtained from anonymised electronic patient records that are routinely collected into GPRD. This protocol outlines the proposed study designs, data sources, sample size requirements, analysis methods and dissemination plans. Ethical issues are also discussed. DISCUSSION: Results from this study will provide methodological evidence concerning the use of electronic patient records and databases for implementing cluster randomised trials in primary care. The study will also provide substantive findings in respect of electronic record-based interventions to reduce antibiotic prescribing in primary care. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 47558792.