Identifying barriers to the adoption of evidence-based medicine practice in clinical clerks: a longitudinal focus group study

OBJECTIVE

To identify and explore common barriers to the adoption of evidence-based medicine (EBM) practice in the undergraduate setting.

DESIGN

Nested longitudinal, focus group-based, qualitative study. Setting The University of Hong Kong Medical School, Hong Kong, China.

PARTICIPANTS

A group of 39 Year 4 medical undergraduates who participated in an EBM intervention cluster randomised crossover trial.

MAIN OUTCOME MEASURES

Students' attitudes, opinions and perceptions of barriers to EBM use.

RESULTS

General attitudes towards EBM and the teaching intervention were positive. Four sets of barriers to greater EBM use were identified as follows. (1) Learning environment including prevailing norms for student learning involving examination-oriented, textbook learning, prior availability of clinical practice guidelines, lack of encouragement from teachers and economy of time by utilising teacher expertise. (2) Limitations of evidence consisting of poor point-of-care access to medical literature, difficulty in locating evidence and the perceived low relevance of overseas evidence to Chinese patients. (3) Lack of opportunity to practise EBM due to lack of continuity of care and anxieties about negative teacher attitudes towards EBM use at the point-of-care. (4) Time constraints such as competing study demands and long evidence search time.

CONCLUSIONS

Significant barriers to the successful implementation of EBM learning in the clinical clerkship setting were identified. These can be specifically targeted to ameliorate any inhibition of clinical learning they may impose.

Prepayment was superior to postpayment cash incentives in a randomized postal survey among physicians

OBJECTIVE

Improving response rates, particularly among physicians, is important to minimize nonresponder bias and increase the effective sample size in epidemiologic research. We conducted a randomized trial to examine the impact of prepayment vs. postpayment incentives on response rates.

STUDY DESIGN AND SETTING

Self-completion postal questionnaires were mailed to 949 physicians who were respondents to an earlier survey and representative of the general physician population in Hong Kong. These physicians were randomly allocated to receive a HK dollar 20 cash prepayment incentive that accompanied the survey (n=474) or a postpayment reward of the same amount on receipt of the completed questionnaire (n=475).

RESULTS

The final prepayment response rate was 82.9%, compared with 72.5% in the postpayment arm (P < .001). Of the eight alternative incentive and follow-up strategies evaluated, three lie on the efficiency frontier (i.e., not dominated), including postpayment with three mailings at HK dollar 42.7, prepayment with three mailings at HK dollar 66.5 and prepayment with three mailings and telephone follow-up at HK dollar 112.1 per responder recruited (US dollar 1=HK dollar 7.8).

CONCLUSION

The findings demonstrate that prepayment cash incentives are superior to postpayment of the equivalent amount in improving response rates among a representative sample of Hong Kong physicians. Further research should concentrate on confirming the generalizability of these findings in other health care occupation groups and settings.

Evaluation of a handheld clinical decision support tool for evidence-based learning and practice in medical undergraduates

INTRODUCTION

Handheld computers (PDAs) uploaded with clinical decision support software (CDSS) have the potential to facilitate the adoption of evidence-based medicine (EBM) at the point-of-care among undergraduate medical students. Further evaluation of the usefulness and acceptability of these tools is required.

METHODS

All 169 Year 4 undergraduate medical students at the University of Hong Kong completed a post-randomised controlled trial survey. Primary outcome measures were CDSS/PDA usefulness, satisfaction, functionality and utilisation. Focus groups were also conducted to derive complementary qualitative data on the students' attitudes towards using such new technology.

RESULTS

Overall, the students found the CDSS/PDA useful (mean score = 3.90 out of 6, 95% confidence interval (CI) = 3.78, 4.03). They were less satisfied with the functional features of the CDSS (mean score = 3.45, 95% CI = 3.32, 3.59) and the PDA (mean score = 3.51 95% CI = 3.40, 3.62). Utilisation was low, with the average frequency of use less than once per week. Although students reported a need for information in patient care at least once daily, they infrequently used the CDSS in a clinical setting (20.4 +/- 10.4% of the time), with an average information retrieval success rate of 37.6 +/- 22.1% requiring 63.7 +/- 86.1 seconds. Multivariable regression shows that higher perceived CDSS/PDA usefulness was associated with more supportive faculty attitudes, greater knowledge of EBM, better computer literacy skills and increased use in a clinical setting. Greater satisfaction with the CDSS/PDA was associated with increased use in a clinical setting and higher successful search rates. Qualitative results were consistent with these quantitative findings and yielded additional information on students' underlying feelings that may explain the observations.

CONCLUSIONS

While PDAs uploaded with the CDSS are able to provide students with better access to high quality information, improvements in faculty attitudes, students' knowledge of EBM and computer literacy skills, and having the CDSS specially designed for undergraduate use are essential to increasing student adoption of such point-of-care tools.

Randomised controlled trial of clinical decision support tools to improve learning of evidence based medicine in medical students

OBJECTIVE

To assess the educational effectiveness on learning evidence based medicine of a handheld computer clinical decision support tool compared with a pocket card containing guidelines and a control.

DESIGN

Randomised controlled trial.

SETTING

University of Hong Kong, 2001.

PARTICIPANTS

169 fourth year medical students.

MAIN OUTCOME MEASURES

Factor and individual item scores from a validated questionnaire on five key self reported measures: personal application and current use of evidence based medicine; future use of evidence based medicine; use of evidence during and after clerking patients; frequency of discussing the role of evidence during teaching rounds; and self perceived confidence in clinical decision making.

RESULTS

The handheld computer improved participants' educational experience with evidence based medicine the most, with significant improvements in all outcome scores. More modest improvements were found with the pocket card, whereas the control group showed no appreciable changes in any of the key outcomes. No significant deterioration was observed in the improvements even after withdrawal of the handheld computer during an eight week washout period, suggesting at least short term sustainability of effects.

CONCLUSIONS

Rapid and convenient access to valid and relevant evidence on a portable computing device can improve learning in evidence based medicine, increase current and future use of evidence, and boost students' confidence in clinical decision making.

Waiting Time, Doctor Shopping, and Nonattendance at Specialist Outpatient Clinics

OBJECTIVE

Nonattendance is a major health services research and management issue that has received little attention or systematic study in Asia. We examined the independent associations between waiting time, doctor shopping, and nonattendance in specialist outpatient clinics of 4 large public hospitals in Hong Kong.

RESEARCH DESIGN

Case-control study.

SETTING AND PARTICIPANTS

A total of 6495 attenders and nonattenders enrolled from July 2000 through October 2001. PAIN OUTCOME MEASURES: Odds ratios (ORs) and associated 95% confidence intervals (CI) for nonattendance.

RESULTS

Longer waiting times (adjusted OR2nd quartile, 1.67; 95% CI, 1.38-2.03; adjusted OR3rd quartile, 1.90; 95% CI, 1.56-2.30; adjusted OR4th quartile, 2.30; 95% CI, 1.91-2.78) and doctor-shopping behavior (adjusted OR, 2.91; 95% CI, 2.51-3.38) were independent risk factors for nonattendance. These effects were robust after multivariate adjustment and testing for effect modification. They also appeared to persist uniformly across hospitals and specialties. There was no demonstrable relationship between waiting time and doctor shopping.

CONCLUSIONS

This is the largest study of nonattendance at outpatient clinics and the first such study carried out in Asia. Targeted strategies should be implemented and evaluated using these results to reduce waiting time, doctor shopping, and ultimately nonattendance.

The development and validation of a knowledge, attitude and behaviour questionnaire to assess undergraduate evidence-based practice teaching and learning

OBJECTIVES

Most evidence-based practice (EBP) educational assessment tools evaluated to date have focused on specific knowledge components or technical skills. Other important potential barriers to the adoption of EBP, such as attitudinal, perceptual and behavioural factors, have yet to be studied, especially in the undergraduate setting. Therefore, we developed and validated a knowledge, attitude and behaviour questionnaire designed to evaluate EBP teaching and learning in an undergraduate medical curriculum.

METHODS

We derived the questionnaire from a comprehensive literature review, informed by international and local experts and a Year 5 student focus group. We determined its factor structure and refined and validated the questionnaire according to the responses of a cohort of Year 5 and a combined group of Years 2 and 3 students using principal components factor analysis with varimax rotation. Factor reliability was computed using Cronbach's alpha coefficient. We assessed construct validity by correlating the factors with other measures of EBP activity and examined responsiveness through paired t-test of the pre/post factor mean scores.

RESULTS

A 43-item questionnaire was developed. Four factors were identified from both student groups. The overall questionnaire as well as each factor had high construct validity (Cronbach's alpha > 0.7 for each scale). No significant correlations were found between the 4 factors, confirming their orthogonality. Positive correlations, however, resulted between factor mean scores and other EBP activities. The responsiveness of the questionnaire was satisfactory.

CONCLUSION

A reliable knowledge, attitude and behaviour measure of EBP teaching and learning appropriate for undergraduate medical education has been developed and validated.

Production of dopaminergic neurons for cell therapy in the treatment of Parkinson's disease

Dopaminergic cell therapy is a potential viable treatment for Parkinson's disease. However, lack of a well-characterized cell preparation of known phenotypic composition containing a high percentage of dopaminergic neurons, has prevented a definitive, controlled, pilot clinical trial from being conducted. We report the successful in vitro expansion of rat E12 mesencephalic progenitors to produce 5-fold the normal number of dopaminergic neurons. The expanded neurons (MAP2+) were detached, resuspended, and formed into small aggregates of 10-200 neurons containing 25-50% of dopaminergic neurons (TH+) that will likely be optimal for use in successful cell therapy. After storage in DPBS, in 0 mM Ca(2+) for up to 24 h at room temperature, aggregated cells were still 90% viable. These results demonstrate that it might be feasible to use a similar protocol to expand human dopaminergic progenitors in vitro. If successful, the requisite large numbers of dopaminergic neurons required to conduct a pilot clinical trial for Parkinson's disease will be produced in vitro. Indications are that the cells can be maintained at optimal viability for the duration of the neural transplantation procedure, under real operating conditions.

Incentives and barriers that influence clinical computerization in Hong Kong: a population-based physician survey

OBJECTIVE

Given the slow adoption of medical informatics in Hong Kong and Asia, we sought to understand the contributory barriers and potential incentives associated with information technology implementation.

DESIGN AND MEASUREMENTS

A representative sample of 949 doctors (response rate = 77.0%) was asked through a postal survey to rank a list of nine barriers associated with clinical computerization according to self-perceived importance. They ranked seven incentives or catalysts that may influence computerization. We generated mean rank scores and used multidimensional preference analysis to explore key explanatory dimensions of these variables. A hierarchical cluster analysis was performed to identify homogenous subgroups of respondents. We further determined the relationships between the sets of barriers and incentives/catalysts collectively using canonical correlation.

RESULTS

Time costs, lack of technical support and large capital investments were the biggest barriers to computerization, whereas improved office efficiency and better-quality care were ranked highest as potential incentives to computerize. Cost vs. noncost, physician-related vs. patient-related, and monetary vs. nonmonetary factors were the key dimensions explaining the barrier variables. Similarly, within-practice vs external and "push" vs "pull" factors accounted for the incentive variables. Four clusters were identified for barriers and three for incentives/catalysts. Canonical correlation revealed that respondents who were concerned with the costs of computerization also perceived financial incentives and government regulation to be important incentives/catalysts toward computerization. Those who found the potential interference with communication important also believed that the promise of improved care from computerization to be a significant incentive.

CONCLUSION

This study provided evidence regarding common barriers associated with clinical computerization. Our findings also identified possible incentive strategies that may be employed to accelerate uptake of computer systems.

Repeat-cycle study of high-dose intravenous 4162W94 anti-CD4 humanized monoclonal antibody in rheumatoid arthritis. A randomized placebo-controlled trial

OBJECTIVE

Results of an earlier open-label pilot study showed that 4162W94 was a relatively non-depleting anti-CD4 monoclonal antibody that induced >80% down-modulation of CD4 molecules from the surface of T lymphocytes. This placebo-controlled repeat-cycle study was conducted in active rheumatoid arthritis (RA) patients to determine the duration of CD4 blockade required to achieve lasting clinical benefit.

METHODS

Following DMARD washout, 48 patients (i.e. three cohorts of 16 patients) with ACR-defined RA were to be dosed with 1 (cohort 1), 2 (cohort 2) or 3 (cohort 3) cycles of 5x300 mg 4162W94 or placebo (12 and 4 patients per cohort respectively) at monthly intervals. There was at least 3 months of follow-up after dosing. Clinical outcome was assessed in evaluable patients (receiving at least 80% of each dose course) using ACR20 criteria (required on two consecutive visits). CD4 lymphocyte counts and adverse events were also monitored.

RESULTS

Sixteen patients were dosed in each of the first two cohorts; however, the dose was reduced in cohort 3 after five patients had received up to two dose cycles due to accumulating evidence of a high frequency of skin rash. These patients were analysed according to the number of cycles received. A further eight patients received 5x100 mg for one to three cycles prior to stopping the study for administrative reasons. Four of 13 (P=0.119 vs placebo) and 7/13 (P=0.015 vs placebo) in cohorts 1 and 2 respectively achieved ACR20 response on at least two consecutive occasions. No patient receiving 5x100 mg/day or placebo achieved ACR20. Four patients were still responding at the end of the 3-month follow-up period. CD4 lymphocyte suppression (<0.2x10(9)/l on at least two successive occasions) occurred in 11/34 patients who received 4162W94 vs none on placebo. Rash occurred in 21/34 monoclonal antibody-treated patients, including one case of biopsy-confirmed cutaneous vasculitis and 1/11 placebo patients.

CONCLUSION

4162W94 demonstrated significant clinical efficacy in this study. However, because of unacceptable CD4 lymphopenia and rash, the original hypothesis that prolonged CD4 blockade would give lasting clinical benefit was not tested.

Effect of prior revascularization on outcome following percutaneous coronary intervention. NHLBI Dynamic Registry

AIMS

An increasing number of patients undergoing percutaneous coronary intervention (PCI) have experienced previous revascularization procedures. Their outcome after PCI has seldom been compared to that of patients without prior procedures. This study investigates which elements of prior revascularization affect in-hospital and long-term outcome after PCI.

METHODS AND RESULTS

Baseline characteristics as well as in-hospital and 1-year outcomes were compared in 4010 consecutive patients undergoing PCI in the NHLBI Dynamic Registry, categorized by type of prior procedure. In-hospital mortality was lowest and procedural success highest among patients with prior PCI only. Patients with prior coronary artery bypass grafting (CABG) had higher rates for the combined endpoint of death and myocardial infarction (MI) at 1 year compared to patients with no prior procedures. However, in multivariate regression analysis adjusting for potential confounders, neither prior PCI nor prior CABG were independent predictors of death or death/MI at 1 year. Patients with prior procedure had higher rates for repeat PCI and patients with prior PCI had higher rates for CABG during the year following the index procedures. These associations persisted after adjustment for potential confounders. Finally, patients with prior procedures had a higher prevalence of angina at 1 year.

CONCLUSIONS

Due to adverse baseline characteristics, patients with prior CABG have higher rates for death/MI during the first year after PCI and both groups of patients with prior procedures have higher revascularization rates. However, only the associations with repeat revascularization persist after adjustment for baseline and procedural factors.

Physicians' attitudes towards the computerization of clinical practice in Hong Kong: a population study

OBJECTIVE

To identify the prevailing attitudes among physicians to use of computers in the clinical setting and specifically those attitudes that may be associated with the adoption of computers in practice.

DESIGN

A self-completed, 20-question postal questionnaire sent to 4850 randomly selected physicians. The questionnaire focused on details of the physicians' practice; actual computerization of or intention to computerize clinical and administrative functions; attitudes towards computerization; self-perceived computer ability and knowledge; and demographic information. The attitude statements were grouped under four themes according to a factor analysis.

RESULTS

The survey was completed by 897 physicians. Only physicians in 'individual' practices were included in the analysis. This group was further dichotomized into clinical users (those with one or more clinical functions computerized) and non-clinical users. Non-clinical users were older and had fewer specialist qualifications. Although there was strong support for the attitude statements among both groups with regard to the benefit of computerization to patient care, there was much less support for electronic medical records. Non-clinical users were concerned about the potentially negative impact of computerization on the clinical encounter and the perceived high cost of computerization.

DISCUSSION

The attitudes among current clinical users and non-users were substantially different. The most important disincentives to computerization were the potential for interference with the patient-physician encounter and the cost of computerizing multiple practice locations. Turning these disincentives into opportunities for change remains the challenge.

Incidence of Alzheimer's disease in a rural community in India: the Indo-US study

OBJECTIVE

To determine overall and age-specific incidence rates of AD in a rural, population-based cohort in Ballabgarh, India, and to compare them with those of a reference US population in the Monongahela Valley of Pennsylvania.

METHODS

A 2-year, prospective, epidemiologic study of subjects aged > or =55 years utilizing repeated cognitive and functional ability screening, followed by standardized clinical evaluation using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, and the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for the diagnosis, and the Clinical Dementia Rating scale for the staging, of dementia and AD.

RESULTS

Incidence rates per 1000 person-years for AD with CDR > or =0.5 were 3.24 (95% CI: 1.48-6.14) for those aged > or =65 years and 1.74 (95% CI: 0.84-3.20) for those aged > or =55 years. Standardized against the age distribution of the 1990 US Census, the overall incidence rate in those aged > or =65 years was 4.7 per 1000 person-years, substantially lower than the corresponding rate of 17.5 per 1000 person-years in the Monongahela Valley.

CONCLUSION

These are the first AD incidence rates to be reported from the Indian subcontinent, and they appear to be among the lowest ever reported. However, the relatively short duration of follow-up, cultural factors, and other potential confounders suggest caution in interpreting this finding.

Computerization of clinical practice in Hong Kong

The objective of this study was to assess the current level of computerization in clinical practice in Hong Kong through a population-based, physician survey conducted in 2000.A self-completed, 20-question, postal questionnaire was sent to 4850 randomly selected doctors in Hong Kong. We received 897 completed responses. Over one-third of doctors in the overall sample were already recording patient summaries, processing laboratory results and specialist reports, and preparing referral notes electronically. Patient registration (52.2%), billing systems (40.2%), appointment scheduling (39.9%), and payroll (36.9%), were the commonest administrative functions to have been computerized. Seventy per cent of doctors in solo or small-group ('individual') practices did not yet have any clinical function computerized compared with only 30.7% for those working in large, corporate organizations. Similarly, approximately two-thirds of administrative tasks in 'individual' clinics were not computerized, while corporate physicians reported a corresponding percentage of 39.3%. Younger age, male gender, specialist qualifications, more computers in the practice, higher numbers of administrative tasks already computerized, higher levels of knowledge about and positive attitudes towards computer applications in clinical practice were all positively associated with more clinical tasks already computerized in the practice. The present study has systematically documented the extent of clinical computer use in Hong Kong and identified areas for improvement as well as specific groups of physicians who might benefit from targeted efforts promoting computerization in practice.

Exogenous NT-3 and NGF differentially modulate PACAP expression in adult sensory neurons, suggesting distinct roles in injury and inflammation

Expression of pituitary adenylate cyclase-activating polypeptide in sensory neurons varies with injury or inflammation. The neurotrophins NGF and NT-3 are profound regulators of neuronal peptidergic phenotype in intact and injured sensory neurons. This study examined their potential for modulation of PACAP expression in adult rat with intact and injured L4-L6 spinal nerves with or without immediate or delayed intrathecal infusion of NT-3 or NGF. Results indicate that in L5 DRG, few trkC neurons express high levels of PACAP mRNA in the intact state, but many do following injury. The elevated expression in injured neurons is mitigated by NT-3 infusion, suggesting a role for NT-3 in returning the 'injured phenotype' back towards an 'intact phenotype'. NGF dramatically up-regulated PACAP expression in trkA-positive neurons in both intact and injured DRGs, implicating NGF as a positive regulator of PACAP expression in nociceptive neurons. Surprisingly, NT-3 modulates PACAP expression in an antagonistic fashion to NGF in intact neurons, an effect most evident in the trkA neurons not expressing trkC. Both NT-3 and NGF infusion results in decreased detection of PACAP protein in the region of the gracile nuclei, where central axons of the peripherally axotomized large sensory fibers terminate. NGF infusion also greatly increased the amount of PACAP protein detected in the portion of the dorsal horn innervated by small-medium size DRG neurons, while both neurotrophins appear able to prevent the decrease in PACAP expression observed in these afferents with injury. These results provide the first insights into the potential molecules implicated in the complex regulation of PACAP expression in sensory neurons.

Molecular basis of mucopolysaccharidosis type IIIB in emu (Dromaius novaehollandiae): an avian model of Sanfilippo syndrome type B

Sanfilippo syndrome type B, or mucopolysaccharidosis (MPS) IIIB, is an autosomal recessive disease caused by a deficiency of lysosomal alpha-N-acetylglucosaminidase (NAGLU). In Dromaius novaehollandiae (emu), a progressive neurologic disease was recently discovered, which was characterized by NAGLU deficiency and heparan sulfate accumulation. To define the molecular basis, the sequences of the normal emu NAGLU cDNA and gene were determined by PCR-based approaches using primers for highly conserved regions of evolutionarily distant NAGLU homologues. It was observed that the emu NAGLU gene is structurally similar to that of human and mouse, but the introns are considerably shorter. The cDNA had an open reading frame (ORF) of 2259 bp. The deduced amino acid sequence is estimated to share 64% identity with human, 63% with mouse, 41% with Drosophila, 39% with tobacco, and 35% with the Caenorhabditis elegans enzyme. Three normal and two affected emus were studied for nucleotide sequence covering the entire coding region and exon-intron boundaries. Unlike the human gene, emu NAGLU appeared to be highly polymorphic: 19 variations were found in the coding region alone. The two affected emus were found to be homozygous for a 2-bp deletion, 1098-1099delGG, in exon 6. The resulting frameshift predicts a longer ORF of 2370 bp encoding a polypeptide with 37 additional amino acids and 387 altered amino acids. The availability of mutation screening in emus now permits early detection of MPS IIIB in breeding stocks and is an important step in characterizing this unique, naturally occurring avian model for the development of gene transfer studies.

Soy protein isolate consumption protects against azoxymethane-induced colon tumors in male rats

Male Sprague-Dawley rats (F2 generation) that had been fed modified American Institute of Nutrition-93G diets formulated with a single protein source of either casein or soy protein isolate for their entire life received azoxymethane once a week for 2 weeks (s.c., 15 mg/kg) starting at age 90 days. Forty weeks later, all rats were euthanized, the colon was examined visually for masses and these were subsequently evaluated histologically. Rats fed the casein diet had a 50% incidence of colon tumors compared with 12% on soy protein-based diets (P<0.05). These results suggest that consumption of soy protein-containing diets may reduce the risk of developing colon tumors.

Dietary whey protein protects against azoxymethane-induced colon tumors in male rats

Epidemiological studies have suggested a relationship between diet and colon cancer incidence. Results from animal studies suggest that whey protein, but not casein protein, may provide protective effects against experimentally induced breast cancer in animals. In the current study, we investigated the effects of casein and whey diets on chemically induced colon cancer in male rats. Pregnant female Sprague Dawley rats (days 3-4 of gestation) were maintained on modified AIN-93G diets formulated with a single protein source of either casein or whey. Life-time exposure to these diets was studied in the F1 generation (experiment A) or the F2 generation (experiment B). Male offspring were weaned to the same diets as the dams and were maintained on these diets throughout the study. At age 90 days, all rats received azoxymethane once a week for 2 weeks (s.c., 15 mg/kg). Forty weeks after the last azoxymethane injection, all rats were euthanized, the colon was examined visually for tumors, and each tumor was histologically evaluated. The weights and distribution of all of the tumors were recorded. In experiment A, rats fed the casein diet had a 56% incidence of colon tumors compared with 30% of the rats on whey-based diets (P < 0.05). In experiment B, rats fed the casein diet had 50% incidence of colon tumors compared with 29% in the whey group (P < 0.05). There were no significant effects of diet on tumor multiplicity or mass. These results suggest that consumption of whey protein-containing diets may reduce the risk of developing colon tumors.

A prospective study of back belts for prevention of back pain and injury

CONTEXT

Despite scientific uncertainties about effectiveness, wearing back belts in the hopes of preventing costly and disabling low back injury in employees is becoming common in the workplace.

OBJECTIVE

To evaluate the effectiveness of using back belts in reducing back injury claims and low back pain.

DESIGN AND SETTING

Prospective cohort study. From April 1996 through April 1998, we identified material-handling employees in 160 new retail merchandise stores (89 required back belt use; 71 had voluntary back belt use) in 30 states (from New Hampshire to Michigan in the north and from Florida to Texas in the south); data collection ended December 1998, median follow-up was 6(1/2) months.

PARTICIPANTS

A referred sample of 13,873 material handling employees provided 9377 baseline interviews and 6311 (67%) follow-up interviews; 206 (1.4%) refused baseline interview.

MAIN OUTCOME MEASURES

Incidence rate of material-handling back injury workers' compensation claims and 6-month incidence rate of self-reported low back pain.

RESULTS

Neither frequent back belt use nor a belt-requirement store policy was significantly associated with back injury claim rates or self-reported back pain. Rate ratios comparing back injury claims of those who reported wearing back belts usually every day and once or twice a week vs those who reported wearing belts never or once or twice a month were 1.22 (95% confidence interval [CI], 0.87-1.70) and 0.95 (95% CI, 0.56-1.59), respectively. The respective odds ratios for low back pain incidence were 0.97 (95% CI, 0.83-1.13) and 0.92 (95% CI, 0.73-1.16).

CONCLUSIONS

In the largest prospective cohort study of back belt use, adjusted for multiple individual risk factors, neither frequent back belt use nor a store policy that required belt use was associated with reduced incidence of back injury claims or low back pain. JAMA. 2000;284:2727-2732.

Relationships between cerebrovascular events, APOE polymorphism and Alzheimer's disease in a community sample

To investigate whether the APOE*4 allele modified the relationship between cerebrovascular events and Alzheimer's disease (AD), we collected evidence of previous stroke or transient ischemic attack (TIA) and determined APOE genotype among 102 subjects with AD and 375 nondemented subjects in a community-based study of dementia. Subjects with a history of stroke or TIA were twice as likely to have AD as subjects without such a history. However, APOE*4 carriers with a history of stroke/TIA were 5 times more likely than APOE*4 carriers without such a history to have AD (odds ratio = 5.3, 95% confidence interval = 1.4-20.9). History of stroke/TIA had little effect on the likelihood of having AD in subjects without an APOE*4 allele.

Pharmacokinetic, pharmacodynamic and clinical effects of a humanized IgG1 anti-CD4 monoclonal antibody in the peripheral blood and synovial fluid of rheumatoid arthritis patients

BACKGROUND

CD4(+) T cells are important mediators in the pathogenesis of rheumatoid arthritis (RA). In this open-label, dose-escalating study, we examined the pharmacokinetic (PK), clinical, biological and immunological effects of a humanized IgG1 anti-CD4 monoclonal antibody (mAb), 4162W94, in the peripheral blood (PB) and synovial fluid (SF) of RA patients.

METHOD

Twenty-four patients in four cohorts (six patients in each cohort) were allocated to be treated with five consecutive daily doses of 4162W94 (10, 30, 100 or 300 mg i.v.). Disease activity was measured by the American College of Rheumatology (ACR) criteria and disease activity score (DAS). We also measured 4162W94 concentration, the percentage of 4162W94-coated CD4(+) lymphocytes, percentage down-modulation of CD4, interleukin-6 (IL-6) and tumour necrosis factor alpha (TNFalpha) levels in the PB and SF.

RESULTS

A direct relationship between 4162W94 dose, biological response and clinical outcome was seen. Treatment with 10 and 30 mg of 4162W94 for 5 consecutive days resulted in transient coating and down-modulation of CD4(+) lymphocytes, with little effect observed beyond the final dose. However, treatment with 100 and 300 mg resulted in sustained coating and/or down-modulation for 3 weeks and 4 weeks, respectively, in PB and >4 weeks in SF in one patient from the 300 mg cohort. There was a dose-related moderate but transient depression in the CD4(+) lymphocyte count in most patients, with all but three returning to >0.40 x 10(9)/l or >75% baseline by the end of the study period. Significant clinical improvement (ACR 20%) was seen in only 1/6 patients in each of the 10- and 30-mg cohorts; however, 3/6 and 5/5 patients in the 100 and 300-mg cohorts, respectively, were ACR 20% responders. In addition, there were significant reductions in PB acute phase reactants as well as SF IL-6 and TNFalpha concentrations in parallel to clinical improvement.

CONCLUSION

Data from this pilot study suggest that 4162W94 is a clinically active novel immunotherapeutic agent that may suppress inflammation in RA.

Endoglin expression as a measure of microvessel density in cervical cancer

OBJECTIVE

To evaluate endoglin, a membrane protein and member of the transforming growth factor beta-1 receptor complex, as an endothelial marker of angiogenesis in cervical cancer tissues.

METHODS

Tumor tissue was collected from 31 surgically treated stage IB nonbulky (under 5 cm) cervical cancer subjects, and samples were fixed in formalin and embedded in paraffin. Endoglin was stained on 5-microm slide sections by the DAKO Catalyzed Signal Amplification method (DAKO Corporation, Carpinteria, CA). Factor VIII was stained by standard immunohistochemistry. Positively stained microvessels were counted in "hot spots" at 200x magnification. Clinical data were correlated with vessel counts by Spearman correlation. Mean differences in counts were tested using paired t tests.

RESULTS

This staining method for endoglin identified significantly more vessels than the factor VIII method (mean 92 +/- 45 versus 33 +/- 16, P <. 001). Endoglin and factor VIII counts correlated significantly with deep stromal invasion (Spearman rho 0.466 and 0.522, respectively, P <.05); however, only endoglin counts correlated significantly with lymph node metastases (rho =.495, P <.01).

CONCLUSION

Endoglin is stimulated in tumor angiogenesis and might be relatively more specific than commonly used endothelial markers. The endoglin system was more sensitive for staining capillaries in neoplastic cervical tissue, better predicted lymph node metastases, and should be widely applicable for the study of other tumors.

Apolipoprotein E polymorphism and Alzheimer disease: The Indo-US Cross-National Dementia Study

BACKGROUND

The APOE*E4 allele of the gene for apolipoprotein E (APOE) has been reported as a risk factor for Alzheimer disease (AD) to varying degrees in different ethnic groups.

OBJECTIVE

To compare APOE*E4-AD epidemiological associations in India and the United States in a cross-national epidemiological study.

DESIGN

Case-control design within 2 cohort studies, using standardized cognitive screening and clinical evaluation to identify AD and other dementias and polymerase chain reaction to identify APOE genotyping.

PARTICIPANTS

Rural community samples, aged 55 years or older (n=4450) in Ballabgarh, India, and 70 years or older (n=886) in the Monongahela Valley region of southwestern Pennsylvania.

MAIN OUTCOME MEASURES

Criteria of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association for probable and possible AD and Clinical Dementia Rating (CDR) scale for dementia staging.

RESULTS

Frequency of APOE*E4 was significantly lower (P<.001) in Ballabgarh vs the Monongahela Valley (0.07 vs 0.11). Frequency of probable or possible AD, with CDR of at least 1.0, in the Indian vs US samples, was as follows: aged 55 to 69 years, 0.1% (Indian sample only); aged 70 to 79 years, 0.7% vs 3.1%; aged 80 years or older, 4.0% vs 15.7%. Among those aged 70 years or older, adjusted odds ratios (95% confidence interval) for AD among carriers of APOE*E4 vs noncarriers were 3.4 (1.2-9.3) and 2.3 (1.3-4.0) in the Indian and US samples, respectively, and not significantly different between cohorts (P=. 20).

CONCLUSION

This first report of APOE*E4 and AD from the Indian subcontinent shows very low prevalence of AD in Ballabgarh, India, but association of APOE*E4 with AD at similar strength in Indian and US samples. Arch Neurol. 2000.

Altered binding of mutated presenilin with cytoskeleton-interacting proteins

The majority of familial Alzheimer's disease (AD) cases are linked to mutations on presenilin 1 and 2 genes (PS1 and PS2). The normal function of the proteins and the mechanisms underlying early-onset AD are currently unknown. To address this, we screened an expression library for proteins that bind differentially to the wild-type PS1 and mutant in the large cytoplasmic loop (PS1L). Thus we isolated the C-terminal tail of the 170 kDa cytoplasmic linker protein (CLIP-170) and Reed-Sternberg cells of Hodgkin's disease-expressed intermediate filament-associated protein (Restin), cytoplasmic proteins linking vesicles to the cytoskeleton. PS1L binding to CLIP-170/restin requires Ca(2+). Treating cells with thapsigargin or ionomycin increased the mutated PS1 in CLIP-170 immunoprecipitates. Further, PS1 and CLIP-170 co-localize in transfected cells and neuronal cultures.

Preventable hospitalization and avoidable maternity outcomes: implications for access to health services for Medicaid recipients

This study demonstrates how readily available hospital discharge data and small area methods can be used to identify potential problems of access to primary and prenatal outpatient health services for Medicaid populations. We examine whether rates of preventable hospitalization and avoidable maternity outcomes differ across geographic areas by their concentration of Medicaid recipients. Five county and twenty-four intra-county areas in Upstate New York are examined. Individuals living in Medicaid intra-county areas had significantly higher rates of these hospitalizations than persons living in non-Medicaid areas. Public health managers can use these methods to identify and compare areas in which access problems exist and to target and evaluate programs designed to improve access.