Cost-effectiveness analysis of pegylated-liposomal doxorubicin and liposomal daunorubicin treatments in patients with Kaposi's sarcoma

Economic evaluations of new AIDS treatment drugs are important. For physicians treating patients with Kaposi's sarcoma, these issues are especially meaningful since cancer treatment costs for this group of patients are high. Kaposi's sarcoma is the most frequently occurring neoplasm in AIDS patients, affecting about 15% of this population. In our study, a retrospective economic evaluation has been made based on data from two randomized phase III clinical studies of severely immune-compromised HIV-infected individuals and which compares liposomal doxorubicin with liposomal daunorubicin. We have estimated the cost and cost effectiveness of the two drugs. The costs per complete or partial response are USS 18340 for daunorubicin and USS 8871 for doxorubicin. The incremental cost per additional responder by using liposomal doxorubicin instead of liposomal daunorubicin is USS 1910. Sensitivity analysis shows that these results hold over a wide range of assumptions.

Operation Safe Haven: an evaluation of health surveillance and monitoring in an acute setting

From May to June 1999, 3,920 ethnic Albanians from Kosovo arrived in Australia as part of Operation Safe Haven. These people were evacuated from refugee camps in the former Yugoslav Republic of Macedonia. Initial processing in Australia occurred at East Hills Reception Centre, and accommodation for the duration of stay was provided in eight Haven Centres in five States. The arrival of a large number of refugees in a short time frame is unprecedented in Australia. A health surveillance system was developed and critical health data were collected to assess health status and needs, plan care, monitor for potential outbreaks of communicable diseases, track service use, to meet international reporting requirements and document our response to this crisis. In this article the health surveillance system is evaluated and suggestions are offered for the formulation of specific guidelines necessary for health surveillance in acute settings.

Maximal androgen blockade for advanced prostate cancer

OBJECTIVES

This systematic review assessed the effect of maximal androgen blockade (MAB) on survival when compared to castration (medical or surgical) alone for patients with advanced prostate cancer.

SEARCH STRATEGY

Randomized controlled trials were searched in general and specialized databases (MEDLINE, EMBASE, Cancerlit, Cochrane Library, VA Cochrane Prostate Disease register) and by reviewing bibliographies.

SELECTION CRITERIA

All published randomized trials were eligible for inclusion provided they (1) randomized men with advanced prostate cancer to receive a non-steroidal anti-androgen (NSAA) medication in addition to castration (medical or surgical) or to castration alone, and (2) reported overall survival, progression-free survival, cancer-specific survival, and/or adverse events. Eligibility was assessed by two independent reviewers.

DATA COLLECTION AND ANALYSIS

Information on patients, interventions, and outcomes were extracted by two independent reviewers using a standardized form. The main outcome measure for comparing effectiveness was overall survival at 1, 2, and 5 years. Secondary outcome measures included progression-free survival and cancer-specific survival. The relationship of specific NSAA on outcome was evaluated. Additionally, the incidence of adverse effects was measured.

MAIN RESULTS

Twenty trials enrolling 6,320 patients were included. The pooled OR for overall survival was 1.03 (95% CI:0.85 to 1.25), 1.16 (95% CI:1.00 to 1.33), and 1.29 (95% CI:1.11 to 1.50) at 1, 2, and 5 years respectively. Overall survival was only significant at 5 years. The risk difference at 5 years was 0.048 (95% CI:0.02 to 0.077) and NNT at 5 years 20.8. Progression-free survival was improved only at 1 year follow-up (OR=1.38) and cancer-free survival was improved only at 5 years (OR=1.22). Adverse events occurred more frequently in those assigned to MAB and resulted in withdrawal in 10%. Quality of life was measured in only one study favored orchiectomy alone (less diarrhea and better emotional functioning in the first 6 months).

REVIEWER'S CONCLUSIONS

MAB produces a modest overall and cancer-specific survival at 5 years but is associated with increased adverse events and reduced quality of life.

Aldose reductase inhibitors for the prevention and treatment of diabetic peripheral neuropathy

OBJECTIVES

To assess the efficacy of aldose reductase inhibitors in the prevention, reversal or delay in the progression of diabetic peripheral neuropathy.

SEARCH STRATEGY

The Cochrane Diabetes Group's database was searched and the citation lists of identified trials and previous reviews checked. Investigators identified as active in the field were approached for overlooked studies.

SELECTION CRITERIA

Randomised controlled trials of aldose reductase inhibitors versus placebo, no treatment or other treatment in diabetic patients with or without clinical neuropathy.

DATA COLLECTION AND ANALYSIS

Nerve conduction velocity was the only end point measured in all trials. Treatment effect was evaluated in terms of nerve conduction velocity mean difference in median and peroneal motor and median and sural sensory nerves.

MAIN RESULTS

19 trials, testing 4 different aldose reductase inhibitors for between 4 to 208 weeks duration (median 24 weeks), met the inclusion criteria for the meta-analysis. A small but statistically significant reduction in decline of median and peroneal motor nerve conduction velocities was present in the treated group when compared to the control group (weighted mean 0.66 m/s 95% CI 0.18-1.14 m/s and 0.53 m/s 95% CI 0.02-1.04m/s respectively). No clear benefit of aldose reductase inhibitor treatment was observed in either of the sensory nerves.

REVIEWER'S CONCLUSIONS

Although aldose reductase inhibitor treatment has been demonstrated to diminsh the reduction in motor nerve conduction velocity, the clinical relevance of such a change in this outcome measure is uncertain. There was no effect in terms of this outcome measure in the smaller sensory fibres, degeneration of which is primarily responsible for the most common neuropathic syndrome associated with diabetes, that of severe pain and loss of sensation in the extremity leading in some cases to ulceration and eventual amputation.

Reduced baroreflex sensitivity in elderly humans is not due to efferent autonomic dysfunction

A progressive decline in baroreflex sensitivity (BRS) is a characteristic feature of human aging, the basis of which is poorly understood. The purpose of the present study was to determine whether alterations in efferent baroreflex function might contribute to the age-related decrease in BRS. We studied 10 healthy young (mean age 30.5 years; age range 22-40 years; six male) and 10 healthy elderly (mean age 70.7 years; age range 67-75 years; five male) volunteers. We tested efferent cardiac vagal function using the bradycardiac response to the cold face test, and efferent sympathetic function using heart rate and blood pressure responses to four stress tests: (i) low-level cognitive stress, (ii) high-level cognitive stress, (iii) hand immersion in ice water (cold pressor test) and (iv) isometric sustained hand-grip. Haemodynamic responses to these stresses are mediated via efferent baroreflex pathways, whereas the afferent components of each reflex response are independent of afferent baroreflex pathways. BRS was measured from simultaneous Finapres-derived continuous blood pressure and digital ECG R-R interval data using the sequence analysis paradigm. As expected, BRS was significantly reduced in the elderly group (7. 29+/-0.74 ms/mmHg; mean+/-S.E.M.) compared with the young group (13. 84+/-1.13 ms/mmHg; P<0.001). However, neither the bradycardiac responses to the cold face test nor the efferent sympathetically mediated heart rate/blood pressure responses to the stress test battery were significantly different between the young and elderly groups. We conclude that the age-related decrease in BRS is not attributable to impairments in the efferent sympathetic or parasympathetic system components of the baroreceptor reflex pathway.

Costs of care associated with high-dose therapy and autologous transplantation for non-Hodgkin's lymphoma: results from the University of Nebraska Medical Center 1989 to 1995

The purpose of this paper was to (1) comprehensively analyze transplant-related costs for predicted temporal cost shifting and (2) to evaluate whether previous findings of decreasing costs of care persisted using a cost analysis of 353 NHL patients who received autologous stem cell transplantation (SCT) at the University of Nebraska Medical Center. All transplant-related costs between the patient's initial consult and program dismissal were obtained and inflated to constant 1995 dollars. Homogeneous resources were categorized into six cost-drivers and subdivided into outpatient, transplant, and additional inpatient time periods in order to evaluate resource utilization and cost shifting patterns. Between 1989 and 1991 both the average length of stay and comprehensive costs decreased 4.9 days and 14%, respectively. By 1995 additional decreases of 25.7 days and 51% led to an overall 7 year cost decline of 65%. Percent contributions of the six cost-drivers remained similar demonstrating uniformed suppression in transplant-related resource consumption. In contrast, the timing of resource utilization changed dramatically, with transplant hospitalization costs accounting for 83% of the overall costs in 1989, 71% by 1992, and only 45% in 1995, while total outpatient's contribution was 14%, 26% and 49%. Before 1991 ebbing costs were likely related to the development of new technologies such as hematopoietic growth factors and peripheral SCT, while the three-fold larger improvement in costs reported by 1995 are presumably associated with learning curve effects such as organizational changes, increased use of coordinated outpatient facilities, and the more cost-effective use of laboratory tests and pharmaceuticals.

An evidence-based analysis of the effect of busulfan, hydroxyurea, interferon, and allogeneic bone marrow transplantation in treating the chronic phase of chronic myeloid leukemia: developed for the American Society of Hematology

Because there are differing opinions regarding treatment of patients in the chronic phase of chronic myeloid leukemia (CML), the American Society of Hematology convened an expert panel to review and document evidence-based benefits and harms of treatment of CML with busulfan (BUS), hydroxyurea (HU), recombinant interferon-alpha (rIFN-alpha), and bone marrow transplantation (BMT). The primary measure for defining efficacy was survival. Analysis indicated a survival advantage for HU over BUS. Observational studies of rIFN-alpha suffer from numerous biases including sample size, variations in study populations, definitions of hematologic and cytogenetic remissions, and dose. That rIFN-alpha is more efficacious than chemotherapy is demonstrated by 6 prospective randomized trials. For patients with favorable clinical features in chronic phase, compared to HU and BUS, rIFN-alpha improves survival by a median of about 20 months. Most evidence suggests that rIFN-alpha is most effective when combined with other drugs and when given during the earliest stage of the chronic phase. Adding cytarabine to rIFN-alpha adds further survival benefit but increases toxicity. Limitations for evaluating the long-term benefits of allogeneic BMT include the retrospective nature of most studies, incomplete documentation of the clinical characteristics of the patients, paucity of the details on patient selection, lack of control groups, and limitations of survival calculations. Survival curves for BMT show that at least half of the patients transplanted remain alive 5 to 10 years after treatment, whereas similar curves for rIFN-alpha show a continuous relapse rate over time with the curves crossing at about 7 to 8 years. Estimates of long-term survival may be confounded by the selection biases mentioned and the analytic methods used. The magnitude of the incremental increase in benefit with BMT must be weighed against the potential serious harm and death that may accompany the procedure in the short term. The best results with BMT have been obtained when it is performed within 1 to 2 years from diagnosis. Since each treatment option involves tradeoffs between benefit and harm, patient choice must be based on the examination of facts presented in an unbiased fashion. Newly diagnosed younger patients and older patients who are candidates for BMT should also be offered information about IFN-based regimens, the tradeoffs involved, and, if possible, share in the treatment decision. Hopefully this analysis will provide the stimulus for evaluation of other important aspects of CML.

Valuing clinical strategies early in development: a cost analysis of allogeneic peripheral blood stem cell transplantation

Allogeneic peripheral blood stem cell transplantation (alloPBSCT) is an emerging technology. As this technology develops, transplant centers are concerned with looking for technologic advances that will result in improvements in clinical outcomes and lower costs. We provide comparative estimates of costs and resource use for alloPBSCT in comparison to allogeneic bone marrow transplantation (alloBMT) for persons with hematologic malignancies from the time of harvest to 100 days post transplant. A retrospective, cost-identification analysis was conducted for patients in two consecutive phase II clinical trials at the University of Nebraska Medical Center. Identical preparative regimens, graft-versus-host disease prophylaxis, post-transplant hematopoietic colony-stimulating factor treatment regimens, and discharge criteria were used. Total median costs were $18,304 lower for alloPBSCT, with lower costs during recovery; specifically for hospitalization, platelet products, hematopoietic growth factors, intravenous hyperalimentation, supportive care agents, supplies, and antibacterial agents. This study provides preliminary evidence for short-term cost savings associated with alloPBSCT. However, concerns exist over the potential for higher costs due to preliminary reports of higher rates of chronic graft-versus-host disease, as well as more intensive induction regimens that may result in lower relapse rates. The premature adoption of new technologies based on short-term economic factors, in the absence of adequate clinical trial data, may prove to be ill-advised, particularly for complex medical treatments such as allogeneic transplantation.

Quality of life in low-income patients with metastatic prostate cancer: divergent and convergent validity of three instruments

Few studies have evaluated Quality Of Life (QOL) among low-income patients with cancer. Information is needed about the feasibility and psychometric characteristics of QOL instruments in these populations. The purpose of this study was to examine the convergent and discriminant relationships between scales of three QOL instruments: European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC), Functional Assessment of Cancer Therapy--General (FACT), and Quality of Life Index (QLI). Participants included 110 men with metastatic prostate cancer of whom 94% were low income and 62% were African-American. Interviewers administered the questionnaires. Cronbach alpha internal consistency reliabilities were 0.57 to 0.90 for the EORTC, 0.65 to 0.86 for the FACT, and 0.63 for the QLI. Convergent validity was supported for the EORTC and FACT scales measuring emotional, physical, and role/functional dimensions (r = 0.54 to 0.72), but not on scales measuring social function (r = 0.12). Divergent validity was supported between dissimilar scales (r = 0.14 to 0.38). Analysis with receiver operating characteristics curves provided empirical support for the EORTC and FACT as multidimensional measures. These findings suggest that, even in busy clinical settings with low literacy patients, interviewer-administered EORTC and FACT QOL instruments can provide valid and reliable information.

Sphincteric stent versus external sphincterotomy in spinal cord injured men: prospective randomized multicenter trial

PURPOSE

In a prospective randomized multicenter trial we compared the treatment results of conventional external sphincterotomy with those of UroLume sphincteric stent prosthesis placement in men with spinal cord injury and external detrusor-sphincter dyssynergia.

MATERIALS AND METHODS

We randomized 57 men with spinal cord injury in whom urodynamics verified external detrusor-sphincter dyssynergia into 2 groups to undergo either sphincter defeating procedure. We compared the primary urodynamic parameter of maximum detrusor pressure, and secondary urodynamic parameters of bladder capacity and post-void residual urine volume in men who underwent sphincterotomy or sphincteric stent placement. Parameters were measured preoperatively, and 3, 6, 12 and 24 months postoperatively. Patients completed questionnaires regarding voiding sensation and quality of life issues at each followup visit.

RESULTS

Demographic data of the 26 patients treated with sphincterotomy and the 31 treated with sphincteric stent placement were statistically similar. Preoperatively mean maximum detrusor pressure plus or minus standard deviation in sphincterotomy and stent cases was 98.3 +/- 27.6 and 95.7 +/- 27.7 cm. water, respectively (p = 0.73). At 12 months mean maximum detrusor pressure decreased to 48.9 +/- 16.4 and 52.6 +/- 31.6 cm. water in the sphincterotomy and stent groups, respectively (p = 0). Preoperatively mean bladder capacity in sphincterotomy and stent cases was 245 +/- 158 and 251 +/- 145 ml., respectively (p = 0.87). Bladder capacity did not change significantly in either treatment group throughout followup. Preoperatively mean post-void residual urine volume in the sphincterotomy and stent groups was 212 +/- 163 and 168 +/- 114 ml., respectively (p = 0.33). Residual urine volume decreased in each group at some but not all followup evaluations. The duration of hospitalization was greater for sphincterotomy than stenting (p = 0.036). Six stents required explantation.

CONCLUSIONS

The UroLume stent is as effective as conventional external sphincterotomy for treating external detrusor-sphincter dyssynergia. However, sphincteric stent placement is advantageous because it involves shorter hospitalization and is potentially reversible.

Relative effectiveness and cost-effectiveness of methods of androgen suppression in the treatment of advanced prostate cancer

OBJECTIVES

With 184,500 new cases and 39,200 deaths anticipated in 1998, prostate cancer is second only to lung cancer in cancer mortality for men. This report is a systematic review of the evidence from randomized controlled trials on the relative effectiveness of alternative strategies for androgen suppression as treatment of advanced prostate cancer. Three key issues are addressed: (1) the relative effectiveness of the available methods for monotherapy (orchiectomy, luteinizing hormone-releasing hormone [LHRH] agonists, and antiandrogens), (2) the effectiveness of combined androgen blockade compared to monotherapy, and (3) the effectiveness of immediate androgen suppression compared to androgen suppression deferred until clinical progression. Outcomes of interest are overall, cancer-specific, and progression-free survival; time to treatment failure; adverse effects; and quality of life. Two supplementary analyses were conducted for each key question: (1) meta-analysis of overall survival at 2 years (questions 1 and 2) and 5 years (questions 2 and 3), and (2) cost-effectiveness analysis.

SEARCH STRATEGY

The MEDLINE, CANCERLIT, and EMBASE databases were searched from 1966 to March 1998, and Current Contents to August 24, 1998, for the terms: leuprolide (Lupron); goserelin (Zoladex); buserelin (Suprefact); flutamide (Eulexin); nilutamide (Anandron, Nilandron); bicalutamide (Casodex); cyproterone acetate (Androcur); diethylstilbestrol (DES); and orchiectomy (castration, orchidectomy). The search was then limited to human studies indexed under the MeSH term "prostatic neoplasms" and by the UK Cochrane Center search strategy for randomized controlled trials. Total yield was 1,477 references.

SELECTION CRITERIA

We Reports of efficacy outcomes were limited to randomized controlled trials. Phase II studies that reported on withdrawals from therapy and all studies reporting on quality of life were also included.

DATA COLLECTION AND ANALYSIS

The systematic review used a prospectively designed protocol conducted by two independent reviewers, with disagreements resolved by consensus. The meta-analysis combined data on overall survival using a random effects model. The cost-effectiveness analysis used a decision analysis model of advanced prostate cancer with health states and transitions derived from the literature and estimates of effectiveness derived from the meta-analysis. The cost-effectiveness analysis is conducted from a societal perspective, consistent with the guidelines of the U.S. Public Health Service Panel on Cost-Effectiveness in Health and Medicine.

MAIN RESULTS

Survival after treatment with an LHRH agonist is equivalent to survival after orchiectomy. The available LHRH agonists are equally effective, and no LHRH agonist is superior to the other when adverse effects are considered. Survival may be somewhat lower with use of a nonsteroidal antiandrogen. There is no statistically significant difference in survival at 2 years between patients treated with combined androgen blockade or monotherapy. Meta-analysis of the limited data available shows a statistically significant difference in survival at 5 years that favors combined androgen blockade. However, the magnitude of this difference is of questionable clinical significance. For the subgroup of patients with good prognosis, there is no statistically significant difference in survival. Adverse effects leading to withdrawal from therapy occurred more often with combined androgen blockade. No evidence is yet available from randomized controlled trials of androgen suppression initiated at prostate-specific antigen (PSA) rise after definitive therapy for clinically localized disease. For patients who are newly diagnosed with locally advanced or asymptomatic metastatic disease, the evidence is insufficient to determine whether primary androgen suppression initiated at diagnosis improves outcomes. (ABSTRACT TRUNCATED)

Heparinase III limits rat arterial smooth muscle cell proliferation in vitro and in vivo

Heparinase III degrades heparan sulfate proteoglycans, which are co-receptors for growth factors that stimulate arterial proliferation. We assessed the ability of locally-delivered heparinase III to limit medial vascular smooth muscle cell proliferation induced by balloon catheter injury in rat carotid arteries. Whereas vehicle-treated arteries showed 12% of smooth muscle cells proliferating after 2 days, heparinase III (0.022-5.7 mg/kg) treated arteries showed 0.8-4%. Chemically-inactivated heparinase III did not limit proliferation. In isolated rat A10 vascular smooth muscle cells, heparinase III (1 IU/ml) inhibited both PDGF-BB and bFGF mediated increases in proliferation and migration. These results suggest that heparinase III can limit proliferation by affecting heparan sulfate proteoglycan binding growth factors following arterial injury.

Physical, chemical, and histologic changes in dentin caries lesions of primary teeth induced by regular use of polyol chewing gums

A previous clinical trial showed that long-term use of saliva-stimulating polyol (xylitol and sorbitol) chewing gums was associated with arrest of dental caries in young subjects. After a 20-22-month intervention (when the subjects were 8 years old), a total of 23 primary teeth with extensive dentin caries lesions whose surface in clinical examination was found to be totally rehardened (remineralized) could be removed because the teeth were near their physiologic exfoliation time. These teeth were subjected to histologic, microhardness, and electron microscopic tests. The majority of the specimens had been remineralized from the surface by a non-cellular-mediated process within the remaining collapsed, organic extracellular matrix associated with the remaining dentinal surface. Many of the underlying dentinal tubules were filled with a matrix that had been subsequently mineralized. Dental microanalyses showed that the topmost (outer) 20-microm-thick rehardened layer of the lesions exhibited the highest Ca:P ratio, which leveled off at a depth of approximately 150 microm. The rehardened surface layer (normally <0.1 mm in thickness) was significantly (P < 0.001) harder than sound dentin and nearly as hard as sound enamel. Although the main source of the mineral present in the rehardened layer was most likely of salivary origin, some extracellular remineralization was probably mediated by odontoblasts. The results complete the dinical diagnoses of the original trial and suggest that regular use of polyol chewing gums may induce changes in dentin caries lesions, which in histologic and physiochemical studies show typical characteristics of rehardening and mineralization.

Evidence for a common mutation in hereditary pancreatitis

Hereditary pancreatitis is an autosomal dominant disorder with incomplete penetrance. It is characterised by recurring episodes of severe abdominal pain and often presents in childhood. Recently, a mutation in the cationic trypsinogen gene was identified in this disease. Previously, only one mutation at residue 117 of the trypsinogen gene has been found in the five separate hereditary pancreatitis families, four from the USA and one from Italy. Alteration of the Arg117 site is believed to disrupt a fail-safe mechanism for the inactivation of trypsin, leading to autodigestion of the pancreas under certain conditions. Molecular analysis of the trypsinogen gene was carried out on a hereditary pancreatitis family from the UK. The same G to A mutation at residue 117 was identified in this family, suggesting that this is a common mutation in hereditary pancreatitis.

Entrance qualifications and student performance in a hybrid problem based and traditional medical programme

A hybrid problem based learning (PBL) and traditional medical programme was started at the Trinidad campus of the University of the West Indies in 1989. Analyses were carried out to determine the extent to which the entrance qualifications of the students were related to their performances at the examinations in the Phase I (preclinical and paraclinical) and Phase II (clinical) programmes. Students who were admitted on the basis of their results in the secondary school General Certificate of Examination (GCE), 'A' level scored higher at the Phase I, but not at the Phase II, level than those who already had university education. Among the 'A' level students, there was positive correlation between the total 'A' level scores and the examination marks in the medical programme, particularly at the Phase I level. Furthermore, multiple regression analyses indicated that the grades in 'A' level Chemistry and, to a lesser extent in Biology, had the most influence on performances at the Phase I examinations, with much less influence on performances at the Phase II examinations. These results suggest that good grades at 'A' level examinations are significant factors, but not the only important ones, that favour high achievement in the initial stages of this type of PBL/traditional medical programme.

Visual Coping Scenarios to Facilitate Discussion of Coping Responses With Impoverished Women at Risk for AIDS

1. Impoverished and homeless women are prone to coping with life stresses through drug and alcohol use. 2. Visual coping scenarios are culturally sensitive strategies to help impoverished minority women discuss effective coping responses. 3. A visual coping scenario redirects attention from a negative emotional event to an effective problem-focused coping strategy.

HIV and AIDS awareness: an evaluation of a short training programme for midwives

In response to a Department of Health, England, circular encouraging policies of named voluntary antenatal HIV antibody testing, one West Midlands health authority in England introduced a policy of raising the issue proactively at the first antenatal attendance. In order to facilitate this policy a short staff education programme was provided for midwives. This paper reports on part of a study which aimed to evaluate the impact of the HIV awareness training programme. A sample of midwives (n = 65) was randomly selected for inclusion in the study. Thirty-three had attended training and 32 had not. Data were collected using a self-administered questionnaire exploring knowledge of aetiology of HIV/AIDS, knowledge of transmission, knowledge of obstetric and paediatric HIV, attitudes to HIV, issues related to antenatal HIV antibody testing and opinions about the HIV awareness training programme. Results indicated no significant difference in levels of knowledge or in attitude between those who had attended the training programme and those who had not. Similarly, no significant difference was found in terms of how midwives would react to women requesting HIV antibody testing. Many of the results contradict the current literature and as a conclusion it is suggested that there is a need to review HIV-related training for midwives.

An international study of the exposure of children to traffic

OBJECTIVES

To examine the extent of international differences in children's exposure to traffic as pedestrians or bicyclists.

DESIGN

Children's travel patterns were surveyed using a parent-child administered questionnaire. Children were sampled via primary schools, using a probability cluster sampling design.

SETTING

Six cities in five countries: Melbourne and Perth (Australia), Montreal (Canada), Auckland (New Zealand), Umeå (Sweden), and Baltimore (USA).

SUBJECTS

Children aged 6 and 9 years.

MAIN OUTCOME MEASURES

Modes of travel on the school-home journey, total daily time spent walking, and the average daily number of roads crossed.

MAIN FINDINGS

Responses were obtained from the parents of 13423 children. There are distinct patterns of children's travel in the six cities studied. Children's travel in the three Australasian cities, Melbourne, Perth and Auckland, is characterised by high car use, low levels of bicycling, and a steep decline in walking with increasing car ownership. In these cities, over a third of the children sampled spent less than five minutes walking per day. In Montreal, walking and public transport were the most common modes of travel. In Umeå, walking and bicycling predominated, with very low use of motorised transport. In comparison with children in the Australasian and North American cities, children in Umeå spend more time walking, with 87% of children walking for more than five minutes per day.

CONCLUSIONS

There are large international differences in the extent to which children walk and cycle. These findings would suggest that differences in 'exposure to risk' may be an important contributor to international differences in pedestrian injury rates. There are also substantial differences in pedestrian exposure to risk by levels of car ownership-differences that may explain socioeconomic differentials in pedestrian injury rates.