Impact of CONSORT extension for cluster randomised trials on quality of reporting and study methodology: review of random sample of 300 trials, 2000-8

OBJECTIVE

To assess the impact of the 2004 extension of the CONSORT guidelines on the reporting and methodological quality of cluster randomised trials.

DESIGN

Methodological review of 300 randomly sampled cluster randomised trials. Two reviewers independently abstracted 14 criteria related to quality of reporting and four methodological criteria specific to cluster randomised trials. We compared manuscripts published before CONSORT (2000-4) with those published after CONSORT (2005-8). We also investigated differences by journal impact factor, type of journal, and trial setting.

DATA SOURCES

A validated Medline search strategy. Eligibility criteria for selecting studies Cluster randomised trials published in English language journals, 2000-8.

RESULTS

There were significant improvements in five of 14 reporting criteria: identification as cluster randomised; justification for cluster randomisation; reporting whether outcome assessments were blind; reporting the number of clusters randomised; and reporting the number of clusters lost to follow-up. No significant improvements were found in adherence to methodological criteria. Trials conducted in clinical rather than non-clinical settings and studies published in medical journals with higher impact factor or general medical journals were more likely to adhere to recommended reporting and methodological criteria overall, but there was no evidence that improvements after publication of the CONSORT extension for cluster trials were more likely in trials conducted in clinical settings nor in trials published in either general medical journals or in higher impact factor journals.

CONCLUSION

The quality of reporting of cluster randomised trials improved in only a few aspects since the publication of the extension of CONSORT for cluster randomised trials, and no improvements at all were observed in essential methodological features. Overall, the adherence to reporting and methodological guidelines for cluster randomised trials remains suboptimal, and further efforts are needed to improve both reporting and methodology.

Stress fractures in the young athlete: a pictorial review

Stress fractures are an uncommon but important source of pain and disability in young athletes. The presentation and differential diagnosis of stress fractures in young athletes differs from that of older athletes. This pictorial review outlines the pathogenesis and imaging features of stress fractures. Other pathologies that can mimic stress fractures and the advantages of the use of magnetic resonance imaging will be discussed. An imaging algorithm for a suspected stress fracture is suggested.

Detection of cracks in metal sheets using pulsed laser generated ultrasound and EMAT detection

A pulsed Nd:YAG laser with an approximately Gaussian beam shape is directed onto the surface of an aluminium sheet at an energy density below which damage by laser ablation occurs, generating Lamb waves in the sheet. The laser beam is raster scanned across the surface of the sample. The Lamb waves travel radially outwards from the generation point and are detected some distance away by an electromagnetic acoustic transducer with sensitivity to in-plane displacements of the sheet. A number of static EMATs are located around the edges of the sheet, some distance from the generation point. The presence of a crack-like defect on the sheet can be detected by either a sudden change in the ultrasonic waveform or by an enhancement in the frequency content of the waveform when the laser beam illuminates directly onto the crack.

Estimated costs of acute hospital care for people with diabetes in the United Kingdom: a routine record linkage study in a large region

AIMS

Diabetes represents a notable burden to health payers. The purpose of this study was to estimate acute hospital care costs of treating people with diabetes with reference to the costs of treating those without.

METHODS

This was a retrospective study. Data from routine hospital practice were available from a large health region (439 000 people), with an estimated prevalence of diabetes of 3.4%. Common records were identified using probabilistic record linkage. Cost estimates were attributed to admissions using healthcare resource group software. Outpatient costs were attributed using published values. Data described are for 2004, and prices in pounds sterling for 2005. Standardised cost ratios were estimated to compare the costs observed in the diabetes population with those expected from the non-diabetic reference population.

RESULTS

The total annual cost of admissions was pound28 944 811 per 100 000 people, of which pound3 650 869 per 100 000 (12.6%) was diabetes related. The standardised cost rate of inpatient treatment was 2.9. The total cost of outpatient attendances was pound6 589 971 per 100 000, of which pound711 431 per 100 000 (10.8%) was diabetes related. The standardised cost ratio for outpatient care was 4.1. The total cost of hospital care for patients with diabetes was pound11 206 986 per 100 000, or 12.3% of acute hospital expenditure. The combined standardised cost ratio was 3.1. Costs of care for inpatient treatment increased from 8.7% of revenue in 1994 to 12.3% in 2004.

CONCLUSIONS

The costs of acute hospital care for treating people with diabetes increased markedly over a decade, and now exceed 12% of revenue.

Delivering the diabetes education and self management for ongoing and newly diagnosed (DESMOND) programme for people with newly diagnosed type 2 diabetes: cost effectiveness analysis

OBJECTIVES

To assess the long term clinical and cost effectiveness of the diabetes education and self management for ongoing and newly diagnosed (DESMOND) intervention compared with usual care in people with newly diagnosed type 2 diabetes.

DESIGN

We undertook a cost-utility analysis that used data from a 12 month, multicentre, cluster randomised controlled trial and, using the Sheffield type 2 diabetes model, modelled long term outcomes in terms of use of therapies, incidence of complications, mortality, and associated effect on costs and health related quality of life. A further cost-utility analysis was also conducted using current "real world" costs of delivering the intervention estimated for a hypothetical primary care trust.

SETTING

Primary care trusts in the United Kingdom.

PARTICIPANTS

Patients with newly diagnosed type 2 diabetes.

INTERVENTION

A six hour structured group education programme delivered in the community by two professional healthcare educators.

MAIN OUTCOME MEASURES

Incremental costs and quality adjusted life years (QALYs) gained.

RESULTS

On the basis of the data in the trial, the estimated mean incremental lifetime cost per person receiving the DESMOND intervention is pound209 (95% confidence interval - pound704 to pound1137; euro251, -euro844 to euro1363; $326, -$1098 to $1773), the incremental gain in QALYs per person is 0.0392 (-0.0813 to 0.1786), and the mean incremental cost per QALY is pound5387. Using "real world" intervention costs, the lifetime incremental cost of the DESMOND intervention is pound82 (- pound831 to pound1010) and the mean incremental cost per QALY gained is pound2092. A probabilistic sensitivity analysis indicated that the likelihood that the DESMOND programme is cost effective at a threshold of pound20 000 per QALY is 66% using trial based intervention costs and 70% using "real world" costs. Results from a one way sensitivity analysis suggest that the DESMOND intervention is cost effective even under more modest assumptions that include the effects of the intervention being lost after one year.

CONCLUSION

Our results suggest that the DESMOND intervention is likely to be cost effective compared with usual care, especially with respect to the real world cost of the intervention to primary care trusts, with reductions in weight and smoking being the main benefits delivered.

Is it cost effective to introduce paramedic practitioners for older people to the ambulance service? Results of a cluster randomised controlled trial

BACKGROUND

A scheme to train paramedics to undertake a greater role in the care of older people following a call for an emergency ambulance was developed in a large city in the UK.

OBJECTIVES

To assess the cost effectiveness of the paramedic practitioner (PP) scheme compared with usual emergency care.

METHODS

A cluster randomised controlled trial was undertaken of PP compared with usual care. Weeks were allocated to the study group at random to the PP scheme either being active (intervention) or inactive (control). Resource use data were collected from routine sources, and from patient-completed questionnaires for events up to 28 days. EQ-5D data were also collected at 28 days.

RESULTS

Whereas the intervention group received more PP contact time, it reduced the proportion of emergency department (ED) attendances (53.3% vs 84.0%) and time in the ED (126.6 vs 211.3 minutes). There was also some evidence of increased use of health services in the days following the incident for patients in the intervention group. Overall, total costs in the intervention group were 140 UK pounds lower when routine data were considered (p = 0.63). When the costs and QALY were considered simultaneously, PP had a greater than 95% chance of being cost effective at 20 000 UK pounds per QALY.

CONCLUSION

Several changes in resource use are associated with the use of PP. Given these economic results in tandem with the clinical, operational and patient-related benefits, the wider implementation and evaluation of similar schemes should be considered.

Psychological interventions for postnatal depression: cluster randomised trial and economic evaluation. The PoNDER trial

OBJECTIVES

To investigate outcomes for postnatal women attributed to special training for health visitors (HVs) in systematically identifying postnatal depression and delivering psychologically informed interventions, and to establish the cost-effectiveness of the intervention.

DESIGN

A pragmatic randomised cluster trial with clusters allocated to experimental HV training arms or control, with an 18-month follow-up.

SETTING

GP practices in the former Trent Regional Health Authority.

PARTICIPANTS

Women registered with participating GP practices who became 36 weeks pregnant during the recruitment phase of the trial, had a live baby and were on a collaborating HV's caseload for 4 months postnatally.

INTERVENTION

HV training in the assessment of postnatal women, combined with either cognitive behavioural approach (CBA) or person-centred approach (PCA) sessions for eligible women, plus the option of a selective serotonin reuptake inhibitor if indicated.

MAIN OUTCOME MEASURES

The primary outcome was the proportion of at-risk women with a 6-month Edinburgh Postnatal Depression Scale (EPDS) score > or = 12. The primary comparison was between at-risk women in the combined clusters randomised to HV training and women in practices randomised to provide HV usual care. The secondary comparison was to determine any differences between the proportions of women with a 6-month EPDS score > or = 12 in the CBA and PCA groups.

RESULTS

HVs in 101 clusters in 29 primary care trusts collaborated in the study. From 7649 eligible women 4084 (53.4%) consented to take part: 17.3% (595/3449) of women who returned a 6-week questionnaire had a 6-week EPDS score > or = 12 and were at-risk women; 70.3% (418/595) of at-risk women had a 6-month EPDS score available. In total, 45.6% (67/147) of control group (CG) at-risk women had a 6-month EPDS score > or = 12 versus 33.9% (93/271) of intervention group (IG) women (p = 0.036). A total of 32.9% (46/140) of at-risk women in the CBA group versus 35.1% (46/131) in the PCA group had a 6-month EPDS score > or = 12 (p = 0.74). The CG mean 6-month EPDS score for at-risk women was 11.3 (SD 5.8) versus 9.2 (SD 5.4) for the IG (p = 0.002) and this remained statistically significant after adjusting for 6-week variables (p = 0.001). In total, 16.4% (150/914) of all women in the CG had a 6-month EPDS score > or = 12 compared with 11.7% (205/1745) in the IG (p = 0.003). The CG mean 6-month EPDS score for all women was 6.4 (SD 5.2) compared with 5.5 (SD 4.7) for the IG (p < 0.001). The economic analysis results showed a consistent pattern of psychological approaches being cost-effective at funding levels used by the National Institute for Health and Clinical Excellence.

CONCLUSIONS

HV training was effective compared with HV usual care in reducing the proportion of at-risk women with a 6-month EPDS score > or = 12, with a wide confidence interval for the estimated intervention effect, suggesting that the true treatment effect may be small. The effect remained for 1 year. The economic evaluation demonstrated that the HV intervention was highly likely to be cost-effective compared with the control. There was no difference in outcomes between the CBA and the PCA groups.

Cost-effectiveness analysis of different embryo transfer strategies in England

OBJECTIVE

The objective of this study was to assess the cost-effectiveness of different embryo transfer strategies for a single cycle when two embryos are available, and taking the NHS cost perspective.

DESIGN

Cost-effectiveness model.

SETTING

Five in vitro fertilisation (IVF) centres in England between 2003/04 and 2004/05.

POPULATION

Women with two embryos available for transfer in three age groups (<30, 30-35 and 36-39 years).

METHODS

A decision analytic model was constructed using observational data collected from a sample of fertility centres in England. Costs and adverse outcomes are estimated up to 5 years after the birth. Incremental cost per live birth was calculated for different embryo transfer strategies and for three separate age groups: less than 30, 30-35 and 36-39 years.

MAIN OUTCOME MEASURES

Premature birth, neonatal intensive care unit admissions and days, cerebral palsy and incremental cost-effectiveness ratios.

RESULTS

Single fresh embryo transfer (SET) plus frozen single embryo transfer (fzSET) is the more costly in terms of IVF costs, but the lower rates of multiple births mean that in terms of total costs, it is less costly than double embryo transfer (DET). Adverse events increase when moving from SET to SET+fzSET to DET. The probability of SET+fzSET being cost-effective decreases with age. When SET is included in the analysis, SET+fzSET no longer becomes a cost-effective option at any threshold value for all age groups studied.

CONCLUSIONS

The analyses show that the choice of embryo transfer strategy is a function of four factors: the age of the mother, the relevance of the SET option, the value placed on a live birth and the relative importance placed on adverse outcomes. For each patient group, the choice of strategy is a trade-off between the value placed on a live birth and cost.

Effects of maternal nutrient restriction on placental morphology and insulin-like growth factor system expressions

Uteroplacental insufficiency is one of the major causes of fetal growth restriction (FGR) in developed countries. The pathophysiology is likely the result of fetal undernutrition due to the impairment of nutrient and substrate transfer from the mother to the fetus. Fetal undernutrition due to maternal undernutrition is not a major cause of FGR in developed countries compared to developing countries. However, FGR can be reproducibly created in experimental animals by maternal undernutrition, and is commonly utilized to study the pathophysiology of fetal undernutrition in the fetus and the placenta. The insulin-like growth factor (IGF) system is the principal growth factor involved in regulating normal fetal and placental growth and its aberrant expression is associated with the development of FGR. We hypothesized that placenta undergoes adaptive changes in pregnancies with maternal undernutrition, the effects of which are mediated by the IGF system. Methods: A mouse model of FGR was generated in CD-1 mice using maternal total caloric nutrient restriction. At 6.5 days of pregnancy, mice were randomly assigned to the control group (ad libitum diet) or global nutrient restriction (GNR) diet group (70% of predetermined food intake of each gestational day). FGR can be reproducibly induced in the fetuses without effect in litter size. Placentae were collected at 18.5 days and were fixed in 4% paraformaldehyde. Five mm tissue sections were prepared by standard techniques and were stained with hematoxylin & eosin for morphometry, PAS for glycogen staining, and immunohistochemistry against IGF-I and –II, IGFBP-1, -2 and –3 using specific antisera for cell-specific expression of the IGF system. The morphology of the placentae was analyzed using a computerized image analysis system. Results: Placentae were significantly smaller in FGR mice compared to controls (94±4 mg SEM vs 72±3 mg SEM). Preliminary results demonstrate changes in FGR mouse placentae tended to be a result of a reduction in spongiotrophoblast layer (p = 0.066, one-tailed t-test) while the labyrinthine trophoblast layer was maintained. Morphometric analysis of the labyrinth demonstrated an increase in the diameter of both maternal and fetal vessels with a reduction in the thickness of the interchorial layer. The IGF-I and –II, IGFBP-1, IGFBP-2 and IGFBP-3 immunoreactivity were all reduced in FGR placentae compared to the controls. Conclusion: These findings suggest that maternal nutrient restriction induces changes in the placenta that may potentially lead to improved nutrient and substrate transfer from mother to fetus, in an attempt to maintain fetal viability. However, these compensatory changes are not sufficient to maintain growth. These changes may result from the alteration of expression of the IGF system genes.

The role of alpha1-antitrypsin in total hip replacement: a pilot study

BACKGROUND

Lungs exposed to particulate debris may be damaged by proteolytic enzymes during phagocytosis. Damage is worse if patients are deficient in alpha1-antitrypsin (A1AT), which helps neutralise these enzymes. We investigated the possibility that A1AT deficiency contributes to aseptic loosening following total hip replacement (THR) when wear particles are phagocytosed.

METHOD

A1AT level and phenotype were measured in patients attending for revision THR within 15 years of implantation. Periprosthetic lysis was graded from radiographs by three hip surgeons with an interest in revision, blinded to history and A1AT results. Patients were grouped according to presence of high or low levels of lysis radiologically. Mean A1AT levels were calculated for the two groups.

RESULTS

17 patients were recruited, mean age 69.5, mean interval between surgery and onset of pain 8.3 years (2-12). Two were heterozygotes for the less active S form of A1AT and therefore mildly deficient. Time to onset of pain in both was 12 years. Radiographs were available for 12 patients. Combining the results for all reviewers the probability of a difference in the level of A1AT between the high and low lysis groups reached statistical significance (p=0.008). For all reviewers, the mean A1AT level in their high lysis group was raised and greater than that of their low lysis group. Both A1AT-deficient patients were classified as high lysis by all reviewers.

CONCLUSIONS

The incidence of A1AT deficiency is only marginally higher in this group than in the general population therefore A1AT deficiency is unlikely to be a common cause of failure of hip replacements. Elevated levels of A1AT in the presence of lysis suggest that A1AT may play a role in the aetiology of aseptic loosening. A1AT-deficient patients may be at increased risk of osteolysis. Further work is needed to evaluate this and to assess vulnerability of A1AT-deficient patients to lysis.