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F Lecky

Publications and source records attributed to F Lecky.

15 recordsLinked to original sources

Derivation of the children's head injury algorithm for the prediction of important clinical events decision rule for head injury in children.

BACKGROUND: A quarter of all patients presenting to emergency departments are children. Although there are several large, well-conducted studies on adults enabling accurate selection of patients with head injury at high risk for computed tomography scanning, no such study has derived a rule for children. AIM: To conduct a prospective multicentre diagnostic cohort study to provide a rule for selection of high-risk children with head injury for computed tomography scanning. DESIGN: All children presenting to the emergency departments of 10 hospitals in the northwest of England with any severity of head injury were recruited. A tailor-made proforma was used to collect data on around 40 clinical variables for each child. These variables were defined from a literature review, and a pilot study was conducted before the children's head injury algorithm for the prediction of important clinical events (CHALICE) study. All children who had a clinically significant head injury (death, need for neurosurgical intervention or abnormality on a computed tomography scan) were identified. Recursive partitioning was used to create a highly sensitive rule for the prediction of significant intracranial pathology. RESULTS: 22,772 children were recruited over 2 1/2 years. 65% of these were boys and 56% were <5 years old. 281 children showed an abnormality on the computed tomography scan, 137 had a neurosurgical operation and 15 died. The CHALICE rule was derived with a sensitivity of 98% (95% confidence interval (CI) 96% to 100%) and a specificity of 87% (95% CI 86% to 87%) for the prediction of clinically significant head injury, and requires a computed tomography scan rate of 14%. CONCLUSION: A highly sensitive clinical decision rule is derived for the identification of children who should undergo computed tomography scanning after head injury. This rule has the potential to improve and standardise the care of children presenting with head injuries. Validation of this rule in new cohorts of patients should now be undertaken.

Algorithms↗

The effect of working hours on outcome from major trauma.

OBJECTIVE: To determine whether being admitted with major trauma to an emergency department outside rather than within working hours results in an adverse outcome. METHODS: The data were collected from hospitals in England and Wales participating in the Trauma Audit and Research Network (TARN). Data from the TARN database were used. Admission time and discharge status were cross matched, and this was repeated while controlling for Injury Severity Score (ISS) values. Logistic regression was carried out, calculating the effects of Revised Trauma Score (RTS), ISS, age, and time of admission on outcome from major trauma. This allowed observed versus expected mortality rates (Ws) scores to be compared within and outside working hours. As much of the RTS data were missing, this was repeated using the Glasgow Coma Score instead of RTS. RESULTS: In total, 5.2% of people admitted "out of hours" died, compared with 5.3% of people within working hours, and 12.2% of people admitted outside working hours had an ISS score greater than 15, compared with 10.1% admitted within working hours. Outcome in cases with comparable ISS values were very similar (31.1% of cases with ISS >15 died out of hours, compared with 33.5% inside working hours.) The subgroup of data with missing RTS values had a significantly increased risk of death. Therefore, GCS was used to calculate severity adjusted odds of death instead of RTS. However, with either model, Ws scores were identical (both 0%) within and outside working hours. CONCLUSIONS: Out of hours admission does not in itself have an adverse effect on outcome from major trauma.

Adolescent↗

Head injuries: a study evaluating the impact of the NICE head injury guidelines.

BACKGROUND: The NICE head injury guidelines recommend a different approach in the management of head injury patients. It suggests that CT head scan should replace skull x ray (SXR) and observation/admission as the first investigation. We wished to determine the impact of NICE on SXR, CT scan, and admission on all patients with head injury presenting to the ED setting and estimate the cost effectiveness of these guidelines, which has not been quantified to date. DESIGN: Study of head injury patients presenting to two EDs before and after implementation of NICE guidelines METHODS: The rate of SXR, CT scan, and admission were determined six months before and one month after NICE implementation in both centres. The before study also looked at predicted rates had NICE been applied. This enabled predicted and actual cost effectiveness to be determined. RESULT: 1130 patients with head injury were studied in four 1 month periods (two in each centre). At the teaching hospital, the CT head scan rate more than doubled (3% to 7%), the SXR declined (37% to 4%), while the admission rate more than halved (9% to 4%). This represented a saving of 3381 pounds sterling per 100 head injury PATIENTS: greater than predicted with no adverse events. At the District General Hospital, the CT head scan rate more than quadrupled (1.4% to 9%), the SXR dropped (19 to 0.57%), while the admission rate declined (7% to 5%). This represented a saving of 290 pounds sterling per 100 head injury patients: less than predicted. CONCLUSION: The implementation of the NICE guidelines led to a two to fivefold increase in the CT head scan rate depending on the cases and baseline departmental practice. However, the reduction in SXR and admission appears to more than offset these costs without compromising patient outcomes.

Adolescent↗

The implications of NICE guidelines on the management of children presenting with head injury.

BACKGROUND: NICE guidelines for the management of head injury were published in June 2003. Their recommendations differ markedly from previous guidelines published by the Royal College of Surgeons (RCS). In place of skull radiography and admission, computed tomography (CT) is advocated. The impact of these guidelines on service provision in the UK is unknown. METHODS: Data on all clinical correlates of children presenting with any severity of head injury was collected in three hospitals in the northwest of England. The current skull radiograph (SXR), CT scan, and admission rates were determined. The rates of SXR, CT scan, and admission that should have occurred when following either the RCS or NICE guidelines were then determined. RESULTS: Data from 10 965 patients who attended three hospitals between February 2000 and August 2002 was studied. Twenty five per cent of patients received a SXR, 0.9% a CT scan, and 3.7% were admitted. Strict adherence to the RCS guidelines would have resulted in a 50% SXR rate, a 1.6% CT scan rate, and a 7.1% admission rate. Adherence to NICE guidelines would result in a 0.3% SXR rate, an 8.7% CT scan rate, and a 1.4% admission rate, although the CT rate would drop to 6.3% if vomiting three or more times in the under 12s was used instead of more than one vomit. CONCLUSIONS: The new NICE guidelines do not increase the workload caused by patients attending with head injury but they move their management from the observation ward to the radiology department.

Adolescent↗

Article 5. An introduction to estimation--2: from z to t.

Provided the sample size is large enough (that is, n greater than 100), the z statistic can be used to determine the confidence interval estimation of the population mean even when the sigma is not known. In these cases the estimation of the standard error of the mean is used. The z statistic is also valid when determining the population's proportion based upon a large sample. However, when dealing with smaller samples, the z statistic is replaced by the t statistic. This makes it possible to estimate, in a population with an unknown standard deviation: The probability of getting a sample mean greater than or equal to a particular value The value of a sample mean with a particular probability of occurring The probability of getting a sample mean between two particular values The confidence interval for the estimation of the population mean can also be determined using the t statistic.

Bias↗

Trends in trauma care in England and Wales 1989-97. UK Trauma Audit and Research Network.

BACKGROUND: In 1988, the Royal College of Surgeons reported major deficiencies in trauma care in UK hospitals. We investigated whether and how that care has changed in the last decade by use of data collected by the UK Trauma Audit and Research Network. METHODS: We analysed injury-severity, process, and outcome variables from 91602 patients' records on the database at the end of 1997, collected from 97 (49% of trauma-receiving) hospitals in England, Wales, and two in Ireland. We did longitudinal analyses of odds of death, process variables, and individual hospitals' performance. We took account of potential selection bias from missing data and recruitment of new hospitals. FINDINGS: The severity-adjusted odds of death after trauma declined gradually from 1989 (odds ratio 1997/1989 0.63 [95% CI [0.49-0.82]). In 1997, the reduction in odds of death was significant even after adjustment for missing data (ratio 1997/1989 0.72 [0.55-0.92]) and recruitment of new hospitals (0.64 [0.44-0.93]). There was significant variability in the proportion of survivors (adjusted for severity of injury and age) between the highest and lowest 10% of UK hospitals. The time between the call to the emergency services and arrival at hospital increased from 32 min in 1989 to 45 min in 1997, irrespective of injury severity. The proportion of severely injured patients seen first by senior doctors increased from 32% to 60%. INTERPRETATION: Hospital care has made a valuable but variable contribution to reductions in case fatality after injury in the UK in the past 10 years, though further improvement is possible.

Aged↗

An introduction to everyday statistics--1.

Descriptive statistics are used to summarise numerical information so that it is in a more manageable form. There are a variety of ways of carrying this out depending upon what type of data we are dealing with. There is also a choice when presenting data. Graphical and tabular formats are possible but each have strengths and weaknesses. Selection therefore needs to take these into account along with the format of the presentation and the type of data.

Humans↗

An introduction to statistical inference--3.

Statistics inference is used to make comments about a population based upon data from a sample. In a similar manner it can be applied to a population to make an estimate about a sample. It is commonly seen in medical publications when the null hypothesis is being tested. This calculates the probability (p value) of a type I error--that is, that a particular finding is attributable to chance. It is also important to be aware of the chances of a type II error--that is, accepting the null hypothesis when it does not apply. Sample size, point estimate and variability are common factors that will affect the chances of making these two types of errors. Interpreting results therefore needs to take these factors into account as well as the clinical relevance of the findings. Statistical significance does not necessarily mean clinical significance.

Emergency Service, Hospital↗