Demonstrating the economic value of occupational health services

Many large companies operate some form of occupational health service (OHS). More companies now require specific evaluative information to justify the continued provision of an in-house OHS. This is in the face of increased pressure to control costs, combined with an awareness that the service itself can induce activity (supplier-induced demand) and could be substituted with health care provided or even funded outside the company. The lack of routinely collected data and the conceptual difficulty in defining and measuring the outcomes of an OHS provide challenges for economic evaluation. A purely human capital approach, where people are valued by their wage rates, is likely to be insufficient, since OHSs have multiple objectives. These objectives include fulfilling statutory obligations, contributing to the creation of a culture of partnership, reduction of potential costs to the company (sickness benefit, production loss, poor performance, litigation, insurance) and providing a suitable environment for the cost-effective reduction of the social and health service costs of illness at work. Evidence is needed to quantify some of these arguments and demonstrate to decision makers the value generated by OHSs. The aim of this paper is to consider the practicality of different economic evaluation methodologies, specifically cost models, contingent valuation (willingness-to-pay) and development of OHS-specific outcome measures. In considering different approaches, we present the results of our research in two UK companies.

Maternal recall bias, obstetric history and schizophrenia

BACKGROUND

This study sought to clarify the role of obstetric complications (OCs) and maternal recall bias for patients with first episodes of schizophrenia and those at increased risk of the disorder.

METHOD

Subjects at high risk of schizophrenia were compared with people with first-episode schizophrenia and with healthy volunteers. Consenting mothers of subjects were interviewed using a standardised questionnaire for the recall of OCs, and OCs were also measured from records collected at the time of pregnancy and delivery.

RESULTS

High-risk subjects and first-episode patients had higher rates of OCs recalled by their mother than controls, but hospital records showed no differences in OCs between groups. The number of OCs recalled by mothers of the high-risk group was not related to whether the mother had schizophrenia or not, but was related to the maternally rated abnormal childhood behaviour as measured by the Child Behaviour Checklist.

CONCLUSIONS

These results suggest that studies that rely on maternal recall alone are susceptible to bias. The excess of OCs recalled by the mother could be related to abnormal behaviour in their child rather than maternal illness, family history or psychotic symptoms.

Structural MRI of the brain in presumed carriers of genes for schizophrenia, their affected and unaffected siblings

BACKGROUND

Schizophrenia is a highly heritable disorder associated with structural brain abnormalities. The aim of this study was to establish if the gene(s) for schizophrenia are associated with specific abnormalities of brain structure.

SUBJECTS

Six sibships from multiple affected families were recruited. Each sibship consisted of one patient with schizophrenia, one "obligate carrier" without the disorder but with an affected child, and one "non-affected non-carrier". Such sibships are very rare, but present a powerful opportunity to separate the associations of genotype and phenotype. Obligates presumably have the gene(s) but not the disorder, affected siblings have both, whereas non-affected non-carrier siblings have neither.

METHOD

Brain MRI was conducted with a semiautomated region of interest analysis. The risk of false positive findings was reduced by collapsing brain regions and sides into five regions and comparing groups by repeated measures analysis of variance.

RESULTS

In terms of whole brain volumes and volumes of cortical structures, obligates resembled their non-affected non-carrier siblings, both groups having significantly greater volumes than their schizophrenic siblings (p=0.01 and p=0.04). Obligates also had significantly smaller ventricles than their schizophrenic siblings (p=0.03). However, with respect to the amygdalohippocampal complex, the obligates' brains resembled those of their schizophrenic siblings, both groups showing a significant reduction in volume when compared with their non-affected non-carrier siblings (p=0.001).

CONCLUSIONS

In the families studied, reductions in volumes of cortical structures and reductions in whole brain volume seem to be associated with the phenotype of schizophrenia. By contrast, reduced volume of the amygdalohippocampal complex seems to be associated with genetic risk for the disorder even in the absence of disease.

Suppression of the "Quasiclassical" proximity gap in correlated-metal--superconductor structures

We study the energy and spatial dependence of the local density of states in a superconductor--correlated-metal--superconductor Josephson junction, where the correlated metal is a non-Fermi liquid (described by the Falicov-Kimball model). Many-body correlations are treated with dynamical mean-field theory, extended to inhomogeneous systems. While quasiclassical theories predict a minigap in the spectrum of a disordered Fermi liquid which is proximity-coupled within a mesoscopic junction, we find that increasing electron correlations destroy any minigap that might be opened in the absence of many-body correlations.

Sustained attention in young people at high risk for schizophrenia

BACKGROUND

Sustained attention has been found to be impaired in individuals suffering from schizophrenia and their close relatives. This has led to the hypothesis that impaired sustained attention is an indicator of vulnerability to schizophrenia.

METHODS

The Edinburgh High Risk Study used the Continuous Performance Test-Identical Pairs version (CPT-IP) to assess sustained attention in 127 high risk participants, 30 controls and 15 first-episode schizophrenic patients. A second assessment was completed by 59 high risk and 18 control participants 18 months to 2 years after the first.

RESULTS

No differences in attentional capacity were found between the high risk and control groups and there was no association between genetic liability to schizophrenia and poor performance on the CPT-IP. Additionally, no association between occurrence of psychotic symptoms in the high risk group and impaired attentional capacity was found.

CONCLUSIONS

The results suggest that deficits in sustained attention are not indicative of a genetic vulnerability to schizophrenia, and are not associated with the occurrence of psychotic symptoms.

The role of radiography in primary care patients with low back pain of at least 6 weeks duration: a randomised (unblinded) controlled trial

OBJECTIVES

To test the hypotheses that: (1) Lumbar spine radiography in primary care patients with low back pain is not associated with improved patient outcomes, including pain, disability, health status, sickness absence, reassurance, and patient satisfaction or belief in the value of radiography. (2) Lumbar spine radiography in primary care patients with low back pain is not associated with changes in patient management, including medication use, and the use of primary and secondary care services, physical therapies and complementary therapies. (3) Participants choosing their treatment group (i.e. radiography or no radiography) do not have better outcomes than those randomised to a treatment group. (4) Lumbar spine radiography is not cost-effective compared with usual care without lumbar spine radiography.

DESIGN

A randomised unblinded controlled trial.

SETTING

Seventy-three general practices in Nottingham, North Nottinghamshire, Southern Derbyshire, North Lincolnshire and North Leicestershire. Fifty-two practices recruited participants to the trial.

SUBJECTS

Randomised arm: 421 participants with low back pain, with median duration of 10 weeks. Patient preference arm: 55 participants with low back pain, with median duration of 11 weeks.

INTERVENTION

Lumbar spine radiography and usual care versus usual care without radiography.

MAIN OUTCOME MEASURES

Roland adaptation of the Sickness Impact Profile, visual analogue pain scale, health status scale, EuroQol, use of primary and secondary care services, and physical and complementary therapies, sickness absence, medication use, patient satisfaction, reassurance and belief in value of radiography at 3 and 9 months post-randomisation.

RESULTS

Participants randomised to receive an X-ray were more likely to report low back pain at 3 months (odds ratio (OR) = 1.56; 95% confidence interval (CI), 1.02 to 2.40) and had a lower overall health status score (p = 0.02). There were no differences in health or functional status at 9 months. A higher proportion of participants consulted the general practitioner (GP) in the 3 months following an X-ray (OR = 2.72; 95% CI, 1.80 to 4.10). There were no differences in use of any other services, medication use or sickness absence at 3 or 9 months. No serious spinal pathology was identified in either group. The commonest X-ray reports were of discovertebral degeneration and normal findings. Many patients did not perceive their information needs were met within the consultation. Satisfaction with care was greater in the group receiving radiography at 9 months. Participants randomised to receive an X-ray were not less worried, or more reassured about serious disease causing their low back pain. Satisfaction was associated with meeting participants' information needs and reduced belief in the necessity for investigations for low back pain, including X-rays and blood tests. In both groups, at 3 and 9 months 80% of participants would choose to have an X-ray if the choice was available. Participants in the patient preference group achieved marginally better outcomes than those randomised to a treatment group, but the clinical significance of these differences is unclear. Lumbar spine radiography was associated with a net economic loss at 3 and 9 months.

CONCLUSIONS

Lumbar spine radiography in primary care patients with low back pain of at least 6 weeks duration is not associated with improved functioning, severity of pain or overall health status, and is associated with an increase in GP workload. Participants receiving X-rays are more satisfied with their care, but are not less worried or more reassured about serious disease causing their low back pain. CONCLUSIONS - RECOMMENDATIONS FOR FURTHER RESEARCH: Further work is required to develop and test an educational package that educates patients and GPs about the utility of radiography and provides strategies for identifying and meeting the information needs of patients, and the needs of patients and GPs to be reassured about missing serious disease. Guidelines on the management of low back pain in primary care should be consistent about not recommending lumbar spine radiography in patients with low back pain in the absence of red flags for serious spinal pathology, even if the pain has persisted for at least 6 weeks.

Inhibition of potentially anti-apoptotic proteins by antisense protein kinase C-alpha (Isis 3521) and antisense bcl-2 (G3139) phosphorothioate oligodeoxynucleotides: relationship to the decreased viability of T24 bladder and PC3 prostate cancer cells

Isis 3521 and G3139 are 20- and 18-mer phosphorothioate oligonucleotides, respectively, targeted to the protein kinase C (PKC)-alpha and bcl-2 mRNAs. Treatment of T24 bladder and PC3 prostate carcinoma cells with full-length and 3'-truncation mutants of Isis 3521 causes down-regulation of PKC-alpha protein and mRNA. However, at the level of a 15-mer and shorter, down-regulation of mRNA expression is no longer observed. Further, no diminution in cellular viability, as measured by 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide assay, in response to increasing concentrations of paclitaxel, can be observed for these shorter oligomers. These observations not only indicate that PKC-alpha protein expression can be down-regulated by both RNase H-dependent and -independent mechanisms but also that down-regulation of PKC-alpha is insufficient by itself to "chemosensitize" cells. G3139, which down-regulates bcl-2 protein and mRNA expression, also down-regulates PKC-alpha protein and mRNA expression but not that of PKC-betaI, -epsilon, or -zeta. However, the down-regulation of PKC-alpha and bcl-2 are not linked. When the carrier Eufectin 5 is employed, only bcl-2 is down-regulated in both T24 and PC3 cells at 50 nM oligonucleotide concentration. At 100 nM, both bcl-2 and PKC-alpha expression are down-regulated, and only at this concentration can "chemosensitization" to paclitaxel and carboplatin be observed. In contrast, the down-regulation of bcl-2 seems to be linked with that of RelA (p65). However, this too is also not sufficient for chemosensitization, even though it leads to the loss of expression of genes under the putative control of nuclear factor-kappaB and to detachment of the cells from plastic surfaces. These results underscore the complexity of the intracellular requirements for the initiation of chemosensitization to anti-neoplastic agents.

Human and automatic face recognition: a comparison across image formats

Human subjects perform poorly at matching different images of unfamiliar faces. When images are taken by different capture devices (cameras), matching is difficult for human perceivers and also for automatic systems. We test an automatic face recognition system based on principal components analysis (PCA) and compare its performance with that of human subjects tested on the same set of images. A number of variants of the PCA system are compared, using different matching metrics and different numbers of components. PCA performance critically depends on the choice of distance metric, with a Mahalanobis metric consistently outperforming a Euclidean metric. Under optimal conditions, the automatic PCA system exceeds human performance on the same images. We hypothesise that unfamiliar face recognition may be mediated by processes corresponding to rather simple functions of the inputs.

Young people and alcohol: an international insight

A survey of the drinking, smoking and illicit drug use of more than 90 000 teenage school students was carried out in 1999. This exercise, known as the European School Survey Project on Alcohol and other Drugs (ESPAD), revealed marked differences in the substance use patterns of those surveyed in different countries. Teenagers in a group of northern countries reported the highest rates of heavy drinking and intoxication (drunkenness). Teenagers in southern Europe reported much lower levels of such behaviours and experiences. Some of these findings are presented and discussed in relation to aetiology and health promotion.

Global analysis of protein activities using proteome chips

To facilitate studies of the yeast proteome, we cloned 5800 open reading frames and overexpressed and purified their corresponding proteins. The proteins were printed onto slides at high spatial density to form a yeast proteome microarray and screened for their ability to interact with proteins and phospholipids. We identified many new calmodulin- and phospholipid-interacting proteins; a common potential binding motif was identified for many of the calmodulin-binding proteins. Thus, microarrays of an entire eukaryotic proteome can be prepared and screened for diverse biochemical activities. The microarrays can also be used to screen protein-drug interactions and to detect posttranslational modifications.

Bromine and iodine in 1997 UK total diet study samples

Concentrations of bromine and iodine were analysed in samples from the 1997 UK Total Diet Study (TDS) using ICP-MS. The data has been used to estimate dietary exposures of UK consumers to these elements from the typical UK diet. Samples for the 20 TDS food groups were obtained from 20 towns in the UK in 1997 and analysed in 1998/99 for total bromine and total iodine concentrations. These samples were also analysed for 12 other elements. The UK regulatory authority had considered iodine recently, but had not considered bromine before. This survey provides up-to-data baseline data for those two elements. Iodine concentrations are similar to those found in recent surveys. Levels of bromine were consistent with previous data where available. Dietary exposures to bromine and iodine were calculated to see if there were any risks to health from the levels of these elements found in the UK diet. The estimated population average exposure to iodine was 0.25 mg d-1, which is within the range of previous estimates (1995, 0.21 mg d-1; 1991, 0.17 mg d-1; 1985, 0.28 mg d-1). The estimated population average exposure to bromine was 3.6 mg d-1.

Programme approach to managing informed commissioning

The objective of this paper is to examine possible organizational reasons for why UK NHS commissioners have not adopted programme budgeting and marginal analysis (PBMA). This is despite increasing evidence of discontent with current commissioning and priority-setting processes, increasing research evidence demonstrating the potential of PBMA and support for the principles of PBMA. Two separate semistructured surveys of the views of commissioning decision-makers on the use of PBMA were carried out at Grampian Health Board and Newcastle & North Tyneside Health Authority. Twenty-nine decision-makers were interviewed. Both surveys found common barriers to implementation of PBMA, described by respondents as 'institutional inertia'. These were the reactive rather than proactive environment; the fear of 'unnecessary' explicitness; an aversion to unilateral innovation in the current NHS environment; and the demand for concrete evaluation evidence. It is concluded that these qualitative surveys have small samples and cannot claim to be representative. It may be significant that many issues were common to both surveys carried out separately in organizations. It is unlikely that NHS commissioning will independently adopt techniques such as PBMA, given the current commissioning environment and organizational structures. Implementation strategies and future research on such commissioning innovations may need to focus on institutions as well as the interventions.

Effects of 17 beta-estradiol and trimegestone alone, and in combination, on the bone and uterus of ovariectomized rats

Trimegestone is a novel norpregnane progestin, which is being developed, in combination with 17 beta-estradiol, for the treatment of menopausal symptoms and prevention of postmenopausal osteoporosis. A model of osteoporosis in the ovariectomized rat has been used to evaluate the effects of 17 beta-estradiol and trimegestone, alone and in combination, on bone and uterus in these animals. Two treatment protocols were investigated, preventive with treatment starting immediately after ovariectomy and curative with treatment starting 1 or 6 months after ovariectomy. 17 beta-Estradiol was administered subcutaneously at a dose of 10 micrograms/kg/day with trimegestone or norethisterone being administered orally at a dose of 1 mg/kg/day; treatment was given 5 days per week. Treatment on both protocols was for 6 months. Given alone, 17 beta-estradiol maintained bone mass, either partially or completely, when given on the preventive protocol, or on the curative protocol with treatment starting 1 month after ovariectomy; it did not restore bone mass when given on the curative protocol with 6 months lapsing between ovariectomy and start of treatment. Trimegestone did not block the beneficial effects of 17 beta-estradiol on bone. 17 beta-Estradiol induced uterine hypertrophy on all these protocols and this was blocked completely by trimegestone. Trimegestone administered alone had no effect on bone or uterus but, when given in combination with 17 beta-estradiol, it did not inhibit the effect of 17 beta-estradiol in maintaining bone mass but completely blocked its uterotropic effect. Norethisterone at a similar dose did not inhibit the effects of 17 beta-estradiol on bone but also did not block its uterotropic effect.

Genetic liability, illicit drug use, life stress and psychotic symptoms: preliminary findings from the Edinburgh study of people at high risk for schizophrenia

BACKGROUND

Studies of groups at high risk of developing schizophrenia have tended to be based on subjects recruited to the study in their infancy. This paper reports on subjects at genetic high risk for schizophrenia assessed as young adults, close to the age when most onsets of schizophrenia occur.

METHODS

One hundred and fifty-five young people at elevated risk for the development of schizophrenia and 36 controls not at increased risk were assessed on entry to the Edinburgh High Risk Study. The measures included current psychotic symptoms, past and present cannabis and other drug use, lifetime life events and two aspects of genetic liability to schizophrenia.

RESULTS

Cannabis and other illicit drug use were significantly associated with symptoms in both groups. The same held true for the more upsetting life events experienced, but not for less upsetting ones. Within the high-risk group, there was no relationship between symptoms and a measure of genetic loading, but there was some slight evidence of a higher risk of symptoms when affected relatives were on the father's rather than the mother's side of the family.

CONCLUSIONS

Cannabis use, use of other illicit substances and upsetting life events may all lead to psychotic symptoms in vulnerable young people.

Neurodevelopmental indices and the development of psychotic symptoms in subjects at high risk of schizophrenia

BACKGROUND

Neurological 'soft signs' and minor physical anomalies (MPAs) are reported to be more frequent in patients with schizophrenia than in controls.

AIMS

To determine whether these disturbances are genetically mediated, and whether they are central to the genesis of symptoms or epiphenomena.

METHOD

We obtained ratings in 152 individuals who were antipsychotic drug-free and at high risk, some of whom had experienced psychotic symptoms, as well as 30 first-episode patients and 35 healthy subjects.

RESULTS

MPAs and Neurological Evaluation Scale (NES) 'sensory integration abnormalities' were more frequent in high-risk subjects than in healthy controls, but there were no reliable differences between high-risk subjects with and without psychotic symptoms. MPAs were most frequent in high-risk subjects with least genetic liability and NES scores showed no genetic associations.

CONCLUSIONS

The lack of associations with psychotic symptoms and genetic liability to schizophrenia suggests that soft signs and physical anomalies are nonspecific markers of developmental deviance that are not mediated by the gene(s) for schizophrenia.

Brain structure, genetic liability, and psychotic symptoms in subjects at high risk of developing schizophrenia

BACKGROUND

Structural magnetic resonance imaging (MRI) of the brain in patients with schizophrenia has consistently demonstrated several abnormalities. These are thought to be neurodevelopmental in origin, as they have also been described in first episode cases, although there may be a progressive component. It is not known at which point in development these abnormalities are evident, nor to what extent they are genetically or environmentally mediated.

METHODS

One hundred forty-seven high-risk subjects (with at least two affected first or second degree relatives), 34 patients in their first episode, and 36 healthy control subjects received an MRI scan covering the whole brain. After inhomogeneity correction, regions of interest were traced by three group-blind raters with good inter-rater reliability. Regional brain volumes were related to measures of genetic liability to schizophrenia and to psychotic symptoms elicited at structured psychiatric interviews.

RESULTS

High-risk subjects had statistically significantly reduced mean volumes of the left and right amygdalo-hippocampus and thalamus, as compared to healthy control subjects. They also had bilaterally larger amygdalo-hippocampi and bilaterally smaller lenticular nuclei than the schizophrenics. High-risk subjects with symptoms had smaller brains than those without. The volumes of the prefrontal lobes and the thalamus were the only consistent associates of genetic liability.

CONCLUSIONS

Subjects at high risk of developing schizophrenia have abnormalities of brain structure similar to but not identical to those found in schizophrenia. Our results suggest that some structural abnormalities are genetic trait or vulnerability markers, others are environmentally mediated, and that the development of symptoms is associated with a third overlapping group of structural changes. Particular risk factors for schizophrenia may interact at discrete time points of neurodevelopment with different effects on specific brain regions and may represent relatively distinct disease processes.