Maria Prior

Choosing appropriate patient-reported outcomes instrument for glaucoma research: a systematic review of vision instruments

PurposeTo identify vision Patient-Reported Outcomes instruments relevant to glaucoma and assess their content validity.MethodsMEDLINE, MEDLINE in Process, EMBASE and SCOPUS (to January 2009) were systematically searched. Observational studies or randomised controlled trials, published in English, reporting use of vision instruments in glaucoma studies involving adults were included. In addition, reference lists were scanned to identify additional studies describing development and/or validation to ascertain the final version of the instruments. Instruments’ content was then mapped onto a theoretical framework, the World Health Organization International Classification of Functioning, Disability and Health. Two reviewers independently evaluated studies for inclusion and quality assessed instrument content.ResultsThirty-three instruments were identified. Instruments were categorised into thirteen vision status, two vision disability, one vision satisfaction, five glaucoma status, one glaucoma medication related to health status, five glaucoma medication side effects and six glaucoma medication satisfaction measures according to each instruments’ content. The National Eye Institute Visual Function Questionnaire-25, Impact of Vision Impairment and Treatment Satisfaction Survey-Intraocular Pressure had the highest number of positive ratings in the content validity assessment.ConclusionThis study provides a descriptive catalogue of vision-specific PRO instruments, to inform the choice of an appropriate measure of patient-reported outcomes in a glaucoma context.

Application of theory to enhance audit and feedback interventions to increase the uptake of evidence-based transfusion practice: an intervention development protocol

BackgroundAudits of blood transfusion demonstrate around 20% transfusions are outside national recommendations and guidelines. Audit and feedback is a widely used quality improvement intervention but effects on clinical practice are variable, suggesting potential for enhancement. Behavioural theory, theoretical frameworks of behaviour change and behaviour change techniques provide systematic processes to enhance intervention. This study is part of a larger programme of work to promote the uptake of evidence-based transfusion practice.ObjectivesThe objectives of this study are to design two theoretically enhanced audit and feedback interventions; one focused on content and one on delivery, and investigate the feasibility and acceptability.MethodsStudy A (Content): A coding framework based on current evidence regarding audit and feedback, and behaviour change theory and frameworks will be developed and applied as part of a structured content analysis to specify the key components of existing feedback documents. Prototype feedback documents with enhanced content and also a protocol, describing principles for enhancing feedback content, will be developed. Study B (Delivery): Individual semi-structured interviews with healthcare professionals and observations of team meetings in four hospitals will be used to specify, and identify views about, current audit and feedback practice. Interviews will be based on a topic guide developed using the Theoretical Domains Framework and the Consolidated Framework for Implementation Research. Analysis of transcripts based on these frameworks will form the evidence base for developing a protocol describing an enhanced intervention that focuses on feedback delivery. Study C (Feasibility and Acceptability): Enhanced interventions will be piloted in four hospitals. Semi-structured interviews, questionnaires and observations will be used to assess feasibility and acceptability.DiscussionThis intervention development work reflects the UK Medical Research Council’s guidance on development of complex interventions, which emphasises the importance of a robust theoretical basis for intervention design and recommends systematic assessment of feasibility and acceptability prior to taking interventions to evaluation in a full-scale randomised study. The work-up includes specification of current practice so that, in the trials to be conducted later in this programme, there will be a clear distinction between the control (usual practice) conditions and the interventions to be evaluated.

Clinical stakeholders' opinions on the use of selective decontamination of the digestive tract in critically ill patients in intensive care units: an international Delphi study.

IntroductionSelective decontamination of the digestive tract (SDD) is a prophylactic antibiotic regimen that is not widely used in practice. We aimed to describe the opinions of key ‘stakeholders’ about the validity of the existing evidence base, likely consequences of implementation, relative importance of their opinions in influencing overall practice, likely barriers to implementation and perceptions of the requirement for further research to inform the decision about whether to embark on a further large randomised controlled trial.MethodsThis was a Delphi study informed by comprehensive framework of possible determinants of health professionals’ behaviour to study Critical Care practice in four countries. There were four key stakeholder participant groups including ICU physicians, pharmacists, clinical leads, and clinical microbiologists/ infectious disease physicians. Round one comprised participant interviews and Rounds two and three were online questionnaires using Delphi method.ResultsIn this study, 141 participants were recruited of whom 82% were retained. Participants rated themselves as knowledgeable about SDD. Antibiotic resistance was identified as the most important issue. SDD was seen as a low clinical priority but few participants reported strong opposition. There was moderate agreement that research to date has not adequately addressed concerns about antibiotic resistance and lacks generalizability. Participants indicated equipoise with regard to benefits and harms of SDD, and indicated strong support for a further randomised trial.ConclusionsClinicians have clinical equipoise about the effectiveness of SDD. Future research requires longer follow up to assess antibiotic resistance as well as greater validity/generalizability to provide definitive answers on the effectiveness of decontamination and effects on antibiotic resistance. SDD was regarded as not being a high clinical priority, which may limit future trial participation. These results have identified that further large randomised controlled trial of SDD in critical care is both warranted and appropriate.

A theory of how rural health services contribute to community sustainability

Study and opinion suggest that health services play a significant role in supporting the social fabric of fragile rural communities. We draw on empirical evidence about the added-value contributions of health services to communities and unite it with theory of capitals to propose a theoretical model depicting how rural health services contribute to community sustainability. While providing an analytical framework, the paper also points to construction of a measurement tool for enabling planners to measure the contributions of diverse sectors to community sustainability and predict or measure the impact of changes to models of service delivery on the future of rural communities.

Observational study of current use of selective decontamination of the digestive tract in UK Critical Care units

BACKGROUND Evidence supporting selective decontamination of the digestive tract (SDD) is reasonably strong. We set out to determine use in UK critical care units and to compare patient outcomes between units that do and those that do not use SDD. METHODS A total of 250 UK general critical care units were surveyed. Case mix, outcomes, and lengths of stay for admissions to SDD units (with and without an i.v. component) and non-SDD units were compared using data from the Intensive Care National Audit & Research Centre Case Mix Programme database. RESULTS A response was received from all the 250 critical care units surveyed. Of these, 13 (5.2%) reported using SDD on some or all admissions, and of these, 3 reported using an i.v. component. Data on 284,690 admissions (April 2008-March 2011) from units reporting to the ICNARC Case Mix Programme (CMP) were included in the analyses. Admissions to SDD (n=196) and non-SDD (n=9) units were a similar case mix with similar infection rates and average lengths of stay in the unit and hospital. There was no difference in risk-adjusted unit or hospital mortality. The rate of unit-acquired infections in blood was significantly lower in SDD units using an i.v. component. CONCLUSIONS Use of SDD in UK critical care is very low. The rate of unit-acquired infections in blood was significantly lower in SDD units using an i.v. component, but did not translate into a difference in acute hospital mortality or length of stay. There is a need to better understand the barriers to adoption of SDD into clinical practice and such work is underway.

Why do people present late with advanced glaucoma? A qualitative interview study

Objective To explore the presentation behaviours and pathways to detection of adults who first presented to UK hospital eye services with severe glaucoma. Design Semistructured interviews, based on models of diagnostic delay, to obtain a descriptive self-reported account of when and how participants’ glaucoma was detected. Results 11 patients participated (five in Aberdeen, six in Huddersfield). Four participants reported that the optometry appointment at which their glaucoma was detected was their first ever eye test or their first for over 10 years. Seven participants reported attending regular routine optometrist appointments. Their self-reported experiences and pathways to detection describe a variety of missed detection opportunities and delayed referral and treatment. Conclusions The qualitative data suggest that late detection of glaucoma can result from delays at the patient level but, although based on a small sample, delays also occurred at the healthcare provider (system) level both in terms of accuracy of case detection and effective referral. We suggest that current attempts to address the significant burden of over-referral of glaucoma suspects to hospital eye services (a large proportion of which are false positives) must also focus on the issue of false negatives and on reducing missed detection and service delays.

Is it worthwhile to conduct a randomized controlled trial of glaucoma screening in the United Kingdom

Objectives To assess the value of conducting a glaucoma screening randomized controlled trial in the UK. Methods Decision model based economic evaluation and value of information analysis. Model derived from a previous health technology assessment. Model updated in terms of structure and parameter estimates with data from surveys, interviews with members of the public and health care providers and routine sources. Results On average, across a range of ages of initiating screening (40–60 years), glaucoma prevalence (1–5%), screening uptake (30–100%), and the performance of current case finding, screening was not cost-effective at a £30,000 threshold per quality adjusted life year (QALY) from the perspective of the National Health Service (NHS). The societal value of removing all uncertainty around glaucoma screening is £107 million at a threshold of £20,000 per QALY. For informing policy decisions on glaucoma screening, reducing uncertainty surrounding the NHS and personal social care cost of sight impairment (£74 million) was of most value, followed by reducing uncertainty in test performance (£14 million) and uptake of either screening or current eye care (£8 million each). Conclusions A glaucoma screening trial in the UK is unlikely to be the best use of research resources. Further research to quantify the costs of sight impairment falling on the NHS and personal social services is a priority. Further development of glaucoma tests and research into strategies to promote the uptake of screening or current eye care such as through the use of a behavioural intervention would be worthwhile.

Implementing selective digestive tract decontamination in the intensive care unit: A qualitative analysis of nurse-identified considerations

OBJECTIVE To describe factors senior critical care nurses identify as being important to address when introducing selective digestive tract decontamination (SDD) in the clinical setting. BACKGROUND Critically ill patients are at risk of developing ventilator-associated pneumonia (VAP). SDD is one strategy shown to prevent VAP and possibly improve survival in the critically ill. METHODS We performed a secondary analysis of qualitative data obtained from 20 interviews. An inductive thematic analysis approach was applied to data obtained from senior critical care nurses during phase two of a multi-methods study. RESULTS There were four primary considerations identified that should be addressed or considered prior to implementation of SDD. These considerations included education of health care professionals, patient comfort, compatibility of SDD with existing practices, and cost. CONCLUSIONS Despite a lack of experience with, or knowledge of SDD, nurses were able to articulate factors that may influence its implementation and delivery. Organizations or researchers considering implementation of SDD should include nurses as key members of the implementation team.

Theoretical and empirical dimensions of the Aberdeen Glaucoma Questionnaire: a cross sectional survey and principal component analysis

BackgroundTo develop patient-reported outcome instruments, statistical techniques (e.g., principal components analysis; PCA) are used to examine correlations among items and identify interrelated item subsets (empirical factors). However, interpretation and labelling of empirical factors is a subjective process, lacking precision or conceptual basis. We report a novel and reproducible method for mapping between theoretical and empirical factor structures. We illustrate the method using the pilot Aberdeen Glaucoma Questionnaire (AGQ), a new measure of glaucoma-related disability developed using the International Classification of Functioning and Disability (ICF) as a theoretical framework and tested in a sample representing the spectrum of glaucoma severity.MethodsWe used the ICF to code AGQ item content before mailing the AGQ to a UK sample (N = 1349) selected to represent people with a risk factor for glaucoma and people with glaucoma across a range of severity. Reflecting uncertainty in the theoretical framework (items with multiple ICF codes), an exploratory PCA was conducted. The theoretical structure informed our interpretation of the empirical structure and guided the selection of theoretically-derived factor labels. We also explored the discrimination of the AGQ across glaucoma severity groups.Results656 (49%) completed questionnaires were returned. The data yielded a 7-factor solution with a simple structure (using cut-off point of a loading of 0.5) that together accounted for 63% of variance in the scores. The mapping process resulted in allocation of the following theoretically-derived factor labels: 1) Seeing Functions: Participation; 2) Moving Around & Communication; 3) Emotional Functions; 4) Walking Around Obstacles; 5) Light; 6) Seeing Functions: Domestic & Social Life; 7) Mobility. Using the seven factor scores as independent variables in a discriminant function analysis, the AGQ scores resulted in correct glaucoma severity grading of 32.5% of participants (p < 0.001).ConclusionsThis paper addresses a methodological gap in the application of classical test theory (CTT) techniques, such as PCA, in instrument development. Labels for empirically-derived factors are often selected intuitively whereas they can inform existing bodies of knowledge if selected on the basis of theoretical construct labels, which are more explicitly defined and which relate to each other in ways that are evidence based.

Evidence base for an intervention to maximise uptake of glaucoma testing: a theory-based cross-sectional survey.

Objective To identify factors associated with intention to attend a hypothetical eye health test and provide an evidence base for developing an intervention to maximise attendance, for use in studies evaluating glaucoma screening programmes. Design Theory-based cross-sectional survey, based on an extended Theory of Planned Behaviour (TPB) and the Common Sense Self-Regulation Model, conducted in June 2010. Participants General population including oversampling from low socioeconomic areas. Setting Aberdeenshire and the London Boroughs of Lewisham and Southwark, UK. Results From 867 questionnaires posted, 327 completed questionnaires were returned (38%). In hierarchical regression analysis, the three theoretical predictors in the TPB (Attitude, Subjective norm and Perceived Behavioural Control) accounted for two-thirds of the variance in intention scores (adjusted R2=0.65). All three predictors contributed significantly to prediction. Adding ‘Anticipated regret’ as a factor in the TPB model resulted in a significant increase in prediction (adjusted R2=0.74). In the Common Sense Self-Regulation Model, only illness representations about the personal consequences of glaucoma (How much do you think glaucoma would affect your life?) and illness concern (How concerned are you about getting glaucoma?) significantly predicted. The final model explained 75% of the variance in intention scores, with ethnicity significantly contributing to prediction. Conclusions In this population-based sample (including over-representation of lower socioeconomic groupings), the main predictors of intention to attend a hypothetical eye health test were Attitude, Perceived control over attendance, Anticipated regret if did not attend and black ethnicity. This evidence informs the design of a behavioural intervention with intervention components targeting low intentions and predicted to influence health-related behaviours.