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David Torgerson

Publications and source records attributed to David Torgerson.

12 recordsLinked to original sources
PubMed2006

The DAMASK trial protocol: a pragmatic randomised trial to evaluate whether GPs should have direct access to MRI for patients with suspected internal derangement of the knee.

BACKGROUND: Though new technologies like Magnetic Resonance Imaging (MRI) may be accurate, they often diffuse into practice before thorough assessment of their value in diagnosis and management, and of their effects on patient outcome and costs. MRI of the knee is a common investigation despite concern that it is not always appropriate. There is wide variation in general practitioners (GPs) access to, and use of MRI, and in the associated costs. The objective of this study was to resolve uncertainty whether GPs should refer patients with suspected internal derangement of the knee for MRI or to an orthopaedic specialist in secondary care. METHODS/DESIGN: The design consisted of a pragmatic multi-centre randomised trial with two parallel groups and concomitant economic evaluation. Patients presenting in general practice with suspected internal derangement of the knee and for whom their GP was considering referral to an orthopaedic specialist in secondary care were eligible for inclusion. Within practices, GPs or practice nurses randomised eligible and consenting participants to the local radiology department for an MRI examination, or for consultation with an orthopaedic specialist. To ensure that the waiting time from GP consultation to orthopaedic appointment was similar for both trial arms, GPs made a provisional referral to orthopaedics when requesting the MRI examination. Thus we evaluated the more appropriate sequence of events independent of variations in waiting times. Follow up of participants was by postal questionnaires at six, twelve and 24 months after randomisation. This was to ensure that the evaluation covered all events up to and including arthroscopy. DISCUSSION: The DAMASK trial should make a major contribution to the development of evidence-based partnerships between primary and secondary care professionals and inform the debate when MRI should enter the diagnostic pathway.

Adolescent↗
PubMed2006

Randomised, controlled trial of alternating pressure mattresses compared with alternating pressure overlays for the prevention of pressure ulcers: PRESSURE (pressure relieving support surfaces) trial.

OBJECTIVE: To compare whether differences exist between alternating pressure overlays and alternating pressure mattresses in the development of new pressure ulcers, healing of existing pressure ulcers, and patient acceptability. DESIGN: Pragmatic, open, multicentre, randomised controlled trial. SETTING: 11 hospitals in six NHS trusts. PARTICIPANTS: 1972 people admitted to hospital as acute or elective patients. INTERVENTIONS: Participants were randomised to an alternating pressure mattress (n = 982) or an alternating pressure overlay (n = 990). MAIN OUTCOME MEASURES: The proportion of participants developing a new pressure ulcer of grade 2 or worse; time to development of new pressure ulcers; proportions of participants developing a new ulcer within 30 days; healing of existing pressure ulcers; and patient acceptability. RESULTS: Intention to treat analysis found no difference in the proportions of participants developing a new pressure ulcer of grade 2 or worse (10.7% overlay patients, 10.3% mattress patients; difference 0.4%, 95% confidence interval--2.3% to 3.1%, P = 0.75). More overlay patients requested change owing to dissatisfaction (23.3%) than mattress patients (18.9%, P = 0.02). CONCLUSION: No difference was found between alternating pressure mattresses and alternating pressure overlays in the proportion of people who develop a pressure ulcer. TRIAL REGISTRATION: ISRCTN 78646179.

Adult↗
PubMed2006

Pressure relieving support surfaces (PRESSURE) trial: cost effectiveness analysis.

OBJECTIVE: To assess the cost effectiveness of alternating pressure mattresses compared with alternating pressure overlays for the prevention of pressure ulcers in patients admitted to hospital. DESIGN: Cost effectiveness analysis carried out alongside the pressure relieving support surfaces (PRESSURE) trial; a multicentre UK based pragmatic randomised controlled trial. SETTING: 11 hospitals in six UK NHS trusts. PARTICIPANTS: Intention to treat population comprising 1971 participants. MAIN OUTCOME MEASURES: Kaplan Meier estimates of restricted mean time to development of pressure ulcers and total costs for treatment in hospital. RESULTS: Alternating pressure mattresses were associated with lower overall costs (283.6 pounds sterling per patient on average, 95% confidence interval--377.59 pounds sterling to 976.79 pounds sterling) mainly due to reduced length of stay in hospital, and greater benefits (a delay in time to ulceration of 10.64 days on average,--24.40 to 3.09). The differences in health benefits and total costs for hospital stay between alternating pressure mattresses and alternating pressure overlays were not statistically significant; however, a cost effectiveness acceptability curve indicated that on average alternating pressure mattresses compared with alternating pressure overlays were associated with an 80% probability of being cost saving. CONCLUSION: Alternating pressure mattresses for the prevention of pressure ulcers are more likely to be cost effective and are more acceptable to patients than alternating pressure overlays.

Adult↗
PubMed2005

Exploring the relationship between fear of falling and neuroticism: a cross-sectional study in community-dwelling women over 70.

BACKGROUND: Fear of falling in older adults has been associated with generalised anxiety and may lead to avoidance of activities, with a further negative impact on future falls. Individual differences in personality associated with anxiety have not been previously examined in relation to fear of falling. Current assessment measures and interventions designed to reduce fear of falling in older adults do not take into account perceptions of anxiety associated with individual differences in personality. AIM: To determine whether the core personality trait dimension of neuroticism can predict fear of falling in a community-dwelling sample of women > or = 70 years of age. METHODS: Cross-sectional data from 1,691 UK, community-dwelling female participants aged > or = 70 years were examined using multiple and logistic regression analysis. Fear of falling was measured on a 6-point Likert scale. Neuroticism was measured using the Eysenck personality inventory. RESULTS: The significant independent odds ratios (OR) of predicting fear of falling were: neuroticism (OR 1.47 per SD increase, P<0.001), history of falling (OR 1.57, P<0.001), experience of fracture (OR 1.78, P = 0.014), need to use both arms to push up to rise from a chair (OR 1.56, P = 0.001), poor subjective general health, as measured by the SF12 (OR 1.63 per SD decrease, P<0.001) and living alone (OR 1.31, P = 0.031). CONCLUSIONS: Neuroticism seems to be an important psychological factor in the experience of fear of falling in community-dwelling older women. It may be relevant for inclusion in current assessment measures and for consideration in the design of interventions to reduce fear of falling.

Accidental Falls↗
PubMed2005

Differential recruitment in a cluster randomized trial in primary care: the experience of the UK back pain, exercise, active management and manipulation (UK BEAM) feasibility study.

BACKGROUND: Cluster randomized trials, which randomize groups of patients rather than individuals, are commonly used to evaluate healthcare interventions such as training programmes targeted at health professionals. This article reports the dangers of randomizing entire primary care practices when participants cannot be identified before randomization, as shown by a UK national trial. METHOD: The UK BEAM trial, a national cluster randomized 3 x 2 x 2 factorial trial, was designed to evaluate three treatments for back pain in primary care: "active management"; randomized by practice; and spinal manipulation and exercise classes, both randomized by individual. RESULTS: Two hundred and thirty-one participants were recruited in the feasibility study, 165 (141% of expected recruitment) from active (management) practices but only 66 (54% of expected recruitment) from traditional (management) practices. The participants in active practices were significantly different from those in traditional practices, notably in suffering from milder back pain. CONCLUSIONS: The feasibility study highlighted the dangers of randomizing clusters when individuals cannot be identified beforehand. Different numbers and types of participants were recruited in the two types of cluster. This differential recruitment led us to change the main trial design by abandoning practice level randomization. Instead all practices were trained in active management to maximize recruitment. Ideally cluster randomized trials should identify patients beforehand, to minimize the chance of selection bias. If this is not possible, patient recruitment should be independent in both intervention and control clusters. Pilot studies are especially important for cluster randomized trials, to identify unforeseen problems.

Adult↗
PubMed2004

Increasing response rates to postal questionnaires: a randomised trial of variations in design.

OBJECTIVES: Low response rates to postal questionnaires can threaten the validity of studies by reducing the effective sample size and introducing bias. The identification of methods with which to optimise response rates could, therefore, improve the quality of studies. In an attempt to identify such methods, we undertook a randomised trial of two simple variations in questionnaire design. METHODS: Using a 2 x 2 factorial design, we conducted a randomised trial to test two variations in questionnaire design; the questionnaires were printed on either single-sided or double-sided paper and had either a single- or multiple-booklet layout. Using equal random allocation, 3836 women were randomised to receive one of these questionnaires as part of a study investigating risk factors for osteoporotic fractures. RESULTS: One thousand eight hundred and seventy questionnaires were returned, giving an overall response rate of 48.7%. There were no significant differences in the overall response to each of the four questionnaire designs. When the number of responders who completed at least 50% of each of the three sections was identified, it was found that single-booklet questionnaires had a better response than the multiple-booklet questionnaires and that single-sided questionnaires had a better response than double-sided questionnaires. However, these results were not significant at the 5% level. There were no significant differences in the response to questions on the odd (left-hand side) pages for the single- compared with the double-sided questionnaires. CONCLUSION: As the most cost-effective use of resources, we would advocate the use of double- rather than single-sided questionnaires, and use of a single- rather than multiple-booklet design.

Aged↗
PubMed2003

Evidence for risk of bias in cluster randomised trials: review of recent trials published in three general medical journals.

OBJECTIVE: To examine the prevalence of a risk of bias associated with the design and conduct of cluster randomised controlled trials among a sample of recently published studies. DESIGN: Retrospective review of cluster randomised trials published in the BMJ, Lancet, and New England Journal of Medicine from January 1997 to October 2002. MAIN OUTCOME MEASURES: Prevalence of secure randomisation of clusters, identification of participants before randomisation (to avoid foreknowledge of allocation), differential recruitment between treatment arms, differential application of inclusion and exclusion criteria, and differential attrition. RESULTS: Of the 36 trials identified, 24 were published in the BMJ,11 in the Lancet, and a single trial in the New England Journal of Medicine. At the cluster level, 15 (42%) trials provided evidence for secure allocation and 25 (69%) used stratified allocation. Few trials showed evidence of imbalance at the cluster level. However, some evidence of susceptibility to risk of bias at the individual level existed in 14 (39%) studies. CONCLUSIONS: Some recently published cluster randomised trials may not have taken adequate precautions to guard against threats to the internal validity of their design.

Bias↗
PubMed2003

Randomized clinical trial comparing 2 support surfaces: results of the Prevention of Pressure Ulcers Study.

OBJECTIVE: To determine whether a viscoelastic polymer (energy absorbing) foam mattress was superior to a standard hospital mattress for pressure ulcer prevention and to analyze the cost-effectiveness in comparison with standard hospital mattresses. DESIGN: Unblinded, randomized, prospective trial. SETTING: Elderly acute care, rehabilitation, and orthopedic wards at 3 hospitals in the United Kingdom. PARTICIPANTS: 1168 patients at risk of developing pressure ulcers (Waterlow score, 15 to 20), with a median age of 83 years (25th to 75th percentile range, 79-87). INTERVENTIONS: Participants were allocated to either the experimental equipment (CONFOR-Med mattress/cushion combination) or a standard mattress/cushion combination; all were given standard nursing care. Pressure areas were observed daily. MAIN OUTCOME MEASURE: Development of nonblanching erythema. RESULTS: A significant decrease in the incidence of blanching erythema (26.3% to 19.9%; P =.004) and a nonsignificant decrease in the incidence of nonblanching erythema occurred in participants allocated to the experimental equipment. However, when the survival curve plots were analyzed at 7 days, both categories showed statistically significant decreases (P =.0015 and P =.042, respectively). Participants on standard equipment had a relative odds ratio of 1.36 (95% confidence interval [CI], 1.10-1.69) for developing blanching erythema or worse and 1.46 (95% CI, 0.90-1.82) for developing nonblanching erythema or worse. To prevent nonblanching erythema, the number needed to treat (NNT) was 41.9 (95% CI, -82.6-15.3). To prevent any erythema (blanching or nonblanching), the NNT was 11.5 (95% CI, 41.6-9.3). Participants with blanching or nonblanching erythema were significantly less mobile than participants with normal skin and more likely to have worsening mobility (P <.001). For participants with similar pressure ulcer status, mattress type was not associated with difference in mobility. CONCLUSIONS: Regardless of prevention routine, pressure ulcers occur. In this study, the experimental equipment showed statistical significance to standard equipment for prevention of blanching erythema; significance was not achieved for nonblanching erythema. Trend and survival analysis show that a larger study is required to determine whether this nonsignificant difference is genuine.

Aged↗