Which radiological investigations should be performed to identify fractures in suspected child abuse?

AIMS: To determine which radiological investigations should be performed and which children should be investigated. MATERIALS AND METHODS: An all language literature search of original articles; from 1950-October 2005. Two reviewers independently reviewed each article. A third was carried out on disagreement. Each study was assessed using standardised data extraction, critical appraisal and evidence forms. RESULTS: Thirty-four studies were included. Fifteen addressed the question: which investigation has a higher yield, skeletal surveys (SS) or bone scintigraphy (BS)? Studies gave conflicting results. Overall neither investigation is as good as the two combined. BS predominately missed skull, metaphyseal and epiphyseal fractures, whereas SS commonly missed rib fractures. Two studies showed that a repeat SS 2 weeks after the initial study provided significant additional information about tentative findings, the number and age of fractures. A comparative study evaluated additional oblique views of ribs in 73 children and showed improved diagnostic sensitivity, specificity and accuracy. Four studies addressed the diagnostic yield for occult fractures with respect to age. This was significant for children under 2-years old. CONCLUSIONS: In children under 2-years old, where physical abuse is suspected, diagnostic imaging of the skeleton should be mandatory. SS or BS alone is inadequate to identify all fractures. It is recommended that all SS should include oblique views of the ribs. This review suggests that the following options would optimize the diagnostic yield. However, each needs to be evaluated prospectively: SS that includes oblique views, SS and BS, a SS with repeat SS or selected images 2 weeks later or a BS plus skull radiography and coned views of metaphyses and epiphyses.

Apnoea and brain swelling in non-accidental head injury.

AIMS: (1) To identify whether infants and young children admitted to hospital with subdural haematomas (SDH) secondary to non-accidental head injury (NAHI), suffer from apnoea leading to radiological evidence of hypoxic ischaemic brain damage, and whether this is related to a poor prognosis; and (2) to determine what degree of trauma is associated with NAHI. METHODS: Retrospective case series (1992-98) with case control analysis of 65 children under 2 years old, with an SDH secondary to NAHI. Outcome measures were presenting symptoms, associated injuries and apnoea at presentation, brain swelling or hypoxic ischaemic changes on neuroimaging, and clinical outcome (KOSCHI). RESULTS: Twenty two children had a history of apnoea at presentation to hospital. Apnoea was significantly associated with hypoxic ischaemic brain damage. Severe symptoms at presentation, apnoea, and diffuse brain swelling/hypoxic ischaemic damage were significantly associated with a poor prognosis. Eighty five per cent of cases had associated injuries consistent with a diagnosis of non-accidental injury. CONCLUSIONS: Coma at presentation, apnoea, and diffuse brain swelling or hypoxic ischaemia all predict a poor outcome in an infant who has suffered from SDH after NAHI. There is evidence of associated violence in the majority of infants with NAHI. At this point in time we do not know the minimum forces necessary to cause NAHI. It is clear however that it is never acceptable to shake a baby.

Patterns of injuries to children on public playgrounds.

The incidence and pattern of injuries to children in public playgrounds presenting to the accident and emergency department were reviewed over two six month summer periods in Cardiff. A total of 178 children (mean age 7.5 years) attended with a playground injury representing 1.1% of all the children attending. One hundred and five children fell from equipment, of which the commonest was the climbing frame; 125 children had playground surface related injuries, 86 on bark and 30 on concrete. The pattern of injuries on the playground surfaces was different: fractures and sprains were more common on bark surfaces and lacerations and abrasions on concrete surfaces. Comparison of total injury rates showed there were fewer injuries on modernised playgrounds than expected but these differences were not significant. Modernised playgrounds are more popular, have new exciting equipment, and offer good play opportunities for children. However, the high fracture rate on modernised bark playgrounds is concerning and requires further research.

Internal quality control in clinical chemistry: a teaching review.

This survey introduces the subject of internal quality assessment from a historical point of view, presents a unified approach to notation, concepts and definitions, and describes briefly those quality control procedures that are used most commonly in clinical chemistry. It is not the aim of this report to comment on all the individual contributions made in this field, but rather to concentrate on the principles. Particular emphasis is centered around assessment criteria to compare the efficiencies of selected control procedures for monitoring analyte concentrations in biological fluids. The question of whether to compare control schemes by means of average run lengths, run length distribution functions or average cost functions is considered. A rationalized approach based on the comparison of optimal procedures, using average run length, is adopted.

Dose-interpolation of immunoassay data: uncertainties associated with curve-fitting.

Estimates of analyte concentrations, obtained by immunoassay, have error distributions which are generally underestimated. Better estimates, which take into account the distribution of the response metameter of the calibration curve and uncertainties associated with the location of the fitted curve, have been obtained by computer simulation using practical immunoassay data. The increased use of curve-fitting software in automated immunoassay equipment has prompted the investigation of reported analyte concentration distributions for three commonly used functions, namely the logit-log, the 4-parameter logistic and the four-parameter Amersham models. The stimulation model is of potential value for a variety of situations.

Breast skin temperature rhythms in relation to ovulation.

Breast skin temperatures have been monitored at 30-min intervals throughout wake-span for the whole or part of the menstrual cycle of women aged 20-37 years using both manual and automatic (chronobra) methods of measurement. Circadian breast skin temperature rhythms have been mathematically characterized and rhythm parameters assessed in relation to the estimated time of ovulation. Data generally indicate that there is a peri-ovulatory rise in breast temperature. Computer simulation and practical experiments, based on changes in the residual sums of squares from target values obtained for days in the cycle prior to ovulation, have indicated that this peri-ovulatory increase in temperature is possibly detectable within 24 h. The use of the chronobra and associated statistics may be of value in signalling the onset of the infertile phase of the menstrual cycle.

PIP: Time series analysis was used to characterize circadian breast skin temperature rhythms and to assess their potential in natural family planning. Study subjects were premenopausal women volunteers who were drawn mainly from research staff at the Tenovus Institute and from a group of women in Cardiff practicing natural family planning. These women had no palpable signs of any breast abnormality and 2 women from the Institute were taking oral contraceptives (OCs). These chronophysiological studies of the breast also indluded data from a clinically healthy 9-year-old premenarcheal girl. All measurements of breast skin temperature were generally taken at 30 minute intervals from 0700 to 2300 during wake span for each day of the study. The extremely good linear response of all series to temperature changes, irrespective of the instrument, meant that when calibration data have been applied to observations made during these studies, it is unlikely that the absolute accuracy falls outside 0.10 degrees Centigrade. Prior to the statistical analysis of temperature changes during the menstrual cycle, cosinor analysis was used to investigate the existence of circadian rhythms in women with clinically health breasts for different age groups. Circadian rhythms were demonstrated in all series investigated and the overall 3-year mean and standard deviation of the average mesor, amplitude and acrophase for 4 sensors located on each quadrant of the left breast were calculated using group cosinor analyses and found to be 35.10 (0.32) degrees Centigrade, 0.43 (0.10) degrees Centigrade, and 16 hours and 27 minutes. Comparable values for similarly located sensors obtained from 4 subjects exhibiting normal ovulatory cycles and studied for 1 complete menstrual cycle were 34.13 (0.17) degrees Centigrade, 0.64 (0.05) degrees Centigrade and 21 hours and 6 minutes. Those for 2 subjects on OCs, studied for 1 cycle, were 33.78 (0.24) degrees Centigrade and 22 hours and 9 minutes. Computer simulation and practical experiments, based on changes in the residual sums of squares from target values obtained for days in the cycle prior to ovulation, indicated that this periovulatory increase in temperature is possibly detectable within 24 hours. The use of the chronobra and associated statistics may be of value in signalling the onset of the infertile phase of the menstrual cycle.

The importance of internal quality control data in National External Quality Assessment schemes. Plasma progesterone assays.

Co-ordinators of external quality assessment schemes in the U.K. despatch samples of quality control material to participant laboratories at frequent intervals to assess laboratory performance. We show, via a controlled experiment on the plasma progesterone assay, that the current analysis performed by the external assessors is inadequate and often leads to erroneous conclusions about a laboratory's performance. It is concluded that for a proper assessment of a laboratory's performance, the external assessor should prepare large pools of plasma and distribute them to all participants in the scheme to use as internal quality control material.

Application of Cusum techniques to the routine monitoring of analytical performance in clinical laboratories.

Quality control data from a radioimmunoassay of progesterone are analysed. The measurements are found to have a lognormal distribution. A likelihood analysis of the change-point is described. Some rival continuous inspection schemes are compared and it is pointed out that more efficient schemes than Shewhart's can be implemented in clinical laboratories with the aid of a computer.

Advantages of CUSUM techniques for quality control in clinical chemistry.

The performance of routine analytical laboratories is assessed, inter alia, by the use of appropriate internal quality control techniques. Despite evidence that the cumulative sum technique is generally superior to Shewhart-type control charts and many others, its use has been limited by the popular misconception that it is inferior to Shewhart's in detecting large variations and/or outliers in quality control data. The application of computer simulation methods has enabled us to answer this criticism and has provided the basis for further improvements in the design of the appropriate control scheme for general use in clinical chemistry.

Internal quality control of radioimmunoassays: monitoring of error.

A cumulative sum technique has been specially designed to monitor the error between replicate determinations made on quality control plasma for consecutive batches of assays. This procedure has played a vital role in assessing assay performance. Special consideration has been given to small sample sizes (n = 2 or 3) which is generally the rule rather than the exception in many situations. This technique has been applied to numerous steroid radioimmunoassays and has ensured that both the mean value and the standard error of hormone levels of a quality control pool were under control. Data from routine assays of oestriol and testosterone in plasma from women are presented. Since this technique provides a sensitive measure of monitoring error, it assists the endocrinologist in elucidating statistical inferences which are a manifestation of assay performance.

Internal quality control of radioimmunoassays.

A modified cumulative sum technique has been applied to radioimmunoassay quality control data. The method is approximately 50% more efficient in detecting systematic changes in the mean and variance of quality control values for plasma samples than more widely used conventional methods. The salient features of the technique have been restricted to changes in the mean quality control value of a plasma pool, but potential applications to changes in variance and as a diagnostic aid to problems in radioimmunoassay have been evaluated. The method is independent of computing facilities and statistical expertise since all computations have been presented in the form of a nomogram and thus can be used by technicians at the bench.

A numerical relationship between chromaffin-positive and small intensely fluorescent cells in sympathetic ganglia.

A statistical analysis of counts of small intensely fluorescent (SIF) and chromaffin-positive (CH+) cells in superior cervical, thoracic and coeliac-mesenteric ganglia of rats at various ages (Santer et al. 1975) has been carried out. The results indicate that the numerical distribution of CH+ cells closely follows that of yellow SIF cells but not that of green SIF cells. This relationship holds both for different ganglia and for different ages.