Differences in outcomes of mandatory motorcycle helmet legislation by country income level: A systematic review and meta-analysis.

BACKGROUND: The recent Lancet Commission on Legal Determinants of Global Health argues that governance can provide the framework for achieving sustainable development goals. Even though over 90% of fatal road traffic injuries occur in low- and middle-income countries (LMICs) primarily affecting motorcyclists, the utility of helmet laws outside of high-income settings has not been well characterized. We sought to evaluate the differences in outcomes of mandatory motorcycle helmet legislation and determine whether these varied across country income levels. METHODS AND FINDINGS: A systematic review and meta-analysis were completed using the PRISMA checklist. A search for relevant articles was conducted using the PubMed, Embase, and Web of Science databases from January 1, 1990 to August 8, 2021. Studies were included if they evaluated helmet usage, mortality from motorcycle crash, or traumatic brain injury (TBI) incidence, with and without enactment of a mandatory helmet law as the intervention. The Newcastle-Ottawa Scale (NOS) was used to rate study quality and funnel plots, and Begg's and Egger's tests were used to assess for small study bias. Pooled odds ratios (ORs) and their 95% confidence intervals (CIs) were stratified by high-income countries (HICs) versus LMICs using the random-effects model. Twenty-five articles were included in the final analysis encompassing a total study population of 31,949,418 people. There were 17 retrospective cohort studies, 2 prospective cohort studies, 1 case-control study, and 5 pre-post design studies. There were 16 studies from HICs and 9 from LMICs. The median NOS score was 6 with a range of 4 to 9. All studies demonstrated higher odds of helmet usage after implementation of helmet law; however, the results were statistically significantly greater in HICs (OR: 53.5; 95% CI: 28.4; 100.7) than in LMICs (OR: 4.82; 95% CI: 3.58; 6.49), p-value comparing both strata < 0.0001. There were significantly lower odds of motorcycle fatalities after enactment of helmet legislation (OR: 0.71; 95% CI: 0.61; 0.83) with no significant difference by income classification, p-value: 0.27. Odds of TBI were statistically significantly lower in HICs (OR: 0.61, 95% CI 0.54 to 0.69) than in LMICs (0.79, 95% CI 0.72 to 0.86) after enactment of law (p-value: 0.0001). Limitations of this study include variability in the methodologies and data sources in the studies included in the meta-analysis as well as the lack of available literature from the lowest income countries or from the African WHO region, in which helmet laws are least commonly present. CONCLUSIONS: In this study, we observed that mandatory helmet laws had substantial public health benefits in all income contexts, but some outcomes were diminished in LMIC settings where additional measures such as public education and law enforcement might play critical roles.

Helmet use among motorcycle accident victims in the north-east region of Jamaica.

Currently in Jamaica, motorcyclists account for the largest group of fatalities among all road users. Between 2016 and 2018, a cross sectional study was conducted at the Saint Ann's Bay Regional Hospital involving 155 participants. There were 98.7% males, ages ranged from 14-64 years and more than two thirds of the motorcyclists were under 40 years. Only 29.4% wore helmets, and of those motorcyclists, 52.8% indicated they were only riding for a short distance. Increasing age correlated with increased helmet compliance. Persons with motorcycles greater than 150 cubic centimetres were also more likely to wear a helmet. Interventions to promote increased helmet compliance should take these factors into account in conjunction with enhancing law enforcement.

Unhelmeted Motorcycle Riders Have Increased Injury Burden: A Need to Revisit Universal Helmet Laws.

BACKGROUND: The aim of this study was to compare hospital outcomes for patients in a motorcycle collision with and without helmet use. The study was conducted as a retrospective analysis of the National Trauma Data Bank's 2013 data set, which included reported data from 100 hospitals across the United States. METHODS: Inclusion criterion for this study is a motorcycle crash involving a driver or passenger. The total number of patients in motorcycle crashes as reported by the National Trauma Data Bank in 2013 was 10,345. Helmet use, hospital stay, ICU and ventilation days, mortality, Glasgow Coma Score, Injury Severity Score, patient payer mix, and complication data were obtained. RESULTS: Patients were divided into two groups: those wearing a helmet (n = 6250) and those without (n = 4095). Patients not wearing a helmet had an increased risk of admission to the ICU (OR = 1.36, P < 0.001, CI 1.25-1.48), requiring ventilation support (OR = 1.55, P < 0.001, CI 1.39-1.72), presenting with a Glasgow Coma Score of eight or below (OR = 2.15, P < 0.001), and in-patient mortality (OR = 2.00, P < 0.001, CI 1.58-2.54). Unhelmeted patients were more likely to have government insurance or be uninsured than those patients wearing a helmet (P < 0.001). CONCLUSIONS: It is not well understood why many states are repealing or have repealed universal helmet laws. Lack of helmet use increases the severity of injury in traumatized patients leading to a substantial financial impact on health care costs. Our analysis suggests the need to revisit the issue regarding laws that require protective headwear while riding motorcycles because of the individual and societal impact. LEVEL OF EVIDENCE: III.

MOPEDS: The high cost of cheap and poorly legislated transportation for negligent drivers.

INTRODUCTION: This study evaluates the impact of moped crashes in North Carolina, a state with lenient moped legislation by(1) describing the characteristics of moped crashes and (2) estimating the cost burden of moped-related injuries. METHODS: Health and public records of moped crash subjects treated at our hospital were reviewed. Direct costs were billed hospital charges. Indirect costs based on age and outcomes were calculated. RESULTS: Between 2008-2013, 368 subjects were involved in 373 moped crashes. 52% of drivers were intoxicated. 38% of drivers had prior DWIs and 26% had prior revoked licenses. Hospitalized subjects (n = 305) had a combined 2687 hospital days, 695 ICU days and 449 trips to the operating room for treatment of their injuries. Average hospital charges were $70,561 per subject. Total direct and indirect costs of moped injuries were over $26 million and $81 million respectively. Medicaid absorbed most of the direct cost ($13.7 M). Estimated direct cost of moped crashes across the state totaled $133 million. CONCLUSION: Healthcare and financial ramifications of moped collisions are substantial. Laws governing moped drivers and stricter penalties for intoxicated drivers are needed.

Emergency department visits by pediatric patients sustained as a passenger on a motorcycle.

OBJECTIVE: Currently only 5 out of the 50 states in the United States have laws restricting the age of passengers permitted to ride on a motorcycle. This study sought to characterize the visits by patients under the age of 16 to U.S. emergency departments (EDs) for injuries sustained as a passenger on a motorcycle. METHODS: In this retrospective cohort study, data were obtained from the Nationwide Emergency Department Sample (NEDS) for the years 2006 to 2011. Pediatric patients who were passengers on a motorcycle that was involved in a crash were identified using International Classification of Diseases, Ninth Revision (ICD-9) External Cause of Injury codes. We also examined gender, age, disposition, regional differences, common injuries, and charges. RESULTS: Between 2006 and 2011 there were an estimated 9,689 visits to U.S. EDs by patients under the age of 16 who were passengers on a motorcycle involved in a crash. The overall average patient age was 9.4 years, and they were predominately male (54.5%). The majority (85%) of these patients were treated and released. The average charges for discharged patients were $2,116.50 and amounted to roughly $17,500,000 during the 6 years. The average cost for admission was $51,446 per patient and totaled over $54 million. The most common primary injuries included superficial contusions; sprains and strains; upper limb fractures; open wounds of head, neck, and trunk; and intracranial injuries. CONCLUSION: Although there were only about 9,700 visits to U.S. EDs for motorcycle crashes involving passengers less than 16 years old for 2006 to 2011, the total cost of visits that resulted in either ED discharge or hospital admission amounted to over $71 million.

Has the great recession and its aftermath reduced traffic fatalities?

An analysis of state-level data from 1984 to 2014 provides evidence on the relationship between economic recessions and US traffic fatalities. While there are large reductions associated with decreases in household median income, other policy variables tend to have additional and in some cases, larger effects. An increase in the inequality of the income distribution, measured by the Gini index, has reduced traffic fatalities. Graduated licensing policies, cell phone laws, and motorcycle helmet requirements are all associated with reductions in fatalities. Other factors include a proxy for medical technology, and access to emergency medical services (based on the percent of vehicle miles traveled in rural areas); reductions in the latter accounted for a substantial reduction in fatalities and is likely another indicator of reduced economic activity. Changes in the road network, mainly increases in the percent of collector roads has increased fatalities. Population growth is associated with increased traffic fatalities and changes in age cohorts has a small negative effect. Overall, results suggest that there has been a beneficial impact on traffic fatalities from reduced economic activity, but various policies adopted by the states have also reduced traffic fatalities.

Challenges to validity in single-group interrupted time series analysis.

RATIONALE, AIMS AND OBJECTIVES: Single-group interrupted time series analysis (ITSA) is a popular evaluation methodology in which a single unit of observation is studied; the outcome variable is serially ordered as a time series, and the intervention is expected to "interrupt" the level and/or trend of the time series, subsequent to its introduction. The most common threat to validity is history-the possibility that some other event caused the observed effect in the time series. Although history limits the ability to draw causal inferences from single ITSA models, it can be controlled for by using a comparable control group to serve as the counterfactual. METHOD: Time series data from 2 natural experiments (effect of Florida's 2000 repeal of its motorcycle helmet law on motorcycle fatalities and California's 1988 Proposition 99 to reduce cigarette sales) are used to illustrate how history biases results of single-group ITSA results-as opposed to when that group's results are contrasted to those of a comparable control group. RESULTS: In the first example, an external event occurring at the same time as the helmet repeal appeared to be the cause of a rise in motorcycle deaths, but was only revealed when Florida was contrasted with comparable control states. Conversely, in the second example, a decreasing trend in cigarette sales prior to the intervention raised question about a treatment effect attributed to Proposition 99, but was reinforced when California was contrasted with comparable control states. CONCLUSIONS: Results of single-group ITSA should be considered preliminary, and interpreted with caution, until a more robust study design can be implemented.

Persistent threats to validity in single-group interrupted time series analysis with a cross over design.

RATIONALE, AIMS AND OBJECTIVES: The basic single-group interrupted time series analysis (ITSA) design has been shown to be susceptible to the most common threat to validity-history-the possibility that some other event caused the observed effect in the time series. A single-group ITSA with a crossover design (in which the intervention is introduced and withdrawn 1 or more times) should be more robust. In this paper, we describe and empirically assess the susceptibility of this design to bias from history. METHOD: Time series data from 2 natural experiments (the effect of multiple repeals and reinstatements of Louisiana's motorcycle helmet law on motorcycle fatalities and the association between the implementation and withdrawal of Gorbachev's antialcohol campaign with Russia's mortality crisis) are used to illustrate that history remains a threat to ITSA validity, even in a crossover design. RESULTS: Both empirical examples reveal that the single-group ITSA with a crossover design may be biased because of history. In the case of motorcycle fatalities, helmet laws appeared effective in reducing mortality (while repealing the law increased mortality), but when a control group was added, it was shown that this trend was similar in both groups. In the case of Gorbachev's antialcohol campaign, only when contrasting the results against those of a control group was the withdrawal of the campaign found to be the more likely culprit in explaining the Russian mortality crisis than the collapse of the Soviet Union. CONCLUSIONS: Even with a robust crossover design, single-group ITSA models remain susceptible to bias from history. Therefore, a comparable control group design should be included, whenever possible.

Examination of factors associated with use rates after transition from a universal to partial motorcycle helmet use law.

OBJECTIVES: Motorcycle riders account for a disproportionately high number of traffic injuries and fatalities compared to occupants of other vehicle types. Though research has demonstrated the benefits of helmet use in preventing serious and fatal injuries in the event of a crash, helmet use has remained relatively stable in the United States, where the most recent national estimates show a 64% use rate. Use rates have been markedly lower among those states that do not have a universal helmet law for all riders. In 2012, the state of Michigan repealed its longstanding mandatory helmet use law. In order to gain insights as to the effects of this legislative change, a study was conducted to examine short-term changes in helmet use and identify factors associated with use rates. METHODS: A statewide direct observation survey was conducted 1 year after the transition from a universal helmet law to a partial helmet law. A random parameters logistic regression model was estimated to identify motorcyclist, roadway, and environmental characteristics associated with helmet use. This modeling framework accounts for both intravehicle correlation (between riders and passengers on the same motorcycle) as well as unobserved heterogeneity across riders due to important unobserved factors. RESULTS: Helmet use was shown to vary across demographic segments of the motorcyclist population. Use rates were higher among Caucasian riders, as well as among those age 60 and above. No significant difference was observed between male and female riders. Use was also found to vary geographically, temporally, and with respect to various environmental characteristics. Geographically, helmet use rates tended to be correlated with historical restraint use trends, which may be reflective of riding environment and general differences in the riding population. To this end, rates were also highly variable based upon the type of motorcycle and whether the motorcyclist was wearing high-visibility gear. CONCLUSIONS: The study results demonstrate the short-term reduction in helmet use following transition from a universal to partial motorcycle helmet law. The reduction in use is somewhat less pronounced than has been experienced in other states, which may be reflective of general differences among Michigan motorcyclists because the state has also generally exhibited higher use rates of seat belts and other forms of occupant protection. The study results also highlight potential target areas for subsequent education and public awareness initiatives aimed at increasing helmet use.

Federally mandating motorcycle helmets in the United States.

BACKGROUND: Motorcycle helmets reduce both motorcycle-related fatalities and head injuries. Motorcycle crashes are a major public health concern which place economic stress on the U.S. healthcare system. DISCUSSION: Although statewide universal motorcycle helmet laws effectively increase helmet use, most state helmet laws do not require every motorcycle rider to wear a helmet. Herein, we propose and outline the solution of implementing federal motorcycle helmet law, while addressing potential counterarguments. CONCLUSIONS: The decision to ride a motorcycle without a helmet has consequences that affect more than just the motorcyclist. In an effort to prevent unnecessary healthcare costs, injuries, and deaths, public health efforts to increase helmet use through education and legislation should be strongly considered. Helmet use on motorcycles fits squarely within the purview of the federal government public health and economic considerations.

Helmet regulation in Vietnam: impact on health, equity and medical impoverishment.

BACKGROUND: Vietnam's 2007 comprehensive motorcycle helmet policy increased helmet use from about 30% of riders to about 93%. We aimed to simulate the effect that this legislation might have on: (a) road traffic deaths and non-fatal injuries, (b) individuals' direct acute care injury treatment costs, (c) individuals' income losses from missed work and (d) individuals' protection against medical impoverishment. METHODS AND FINDINGS: We used published secondary data from the literature to perform a retrospective extended cost-effectiveness analysis simulation study of the policy. Our model indicates that in the year following its introduction a helmet policy employing standard helmets likely prevented approximately 2200 deaths and 29 000 head injuries, saved individuals US$18 million in acute care costs and averted US$31 million in income losses. From a societal perspective, such a comprehensive helmet policy would have saved $11 000 per averted death or $830 per averted non-fatal injury. In terms of financial risk protection, traffic injury is so expensive to treat that any injury averted would necessarily entail a case of catastrophic health expenditure averted. CONCLUSIONS: The high costs associated with traffic injury suggest that helmet legislation can decrease the burden of out-of-pocket payments and reduced injuries decrease the need for access to and coverage for treatment, allowing the government and individuals to spend resources elsewhere. These findings suggest that comprehensive motorcycle helmet policies should be adopted by low-income and middle-income countries where motorcycles are pervasive yet helmet use is less common.

Motorcycle Helmets: The Economic Burden of an Incomplete Helmet Law to Medical Care in the State of Connecticut.

The lack of a mandatory motorcycle helmet law leads to increased injury severity and increased health care costs. This study presents a financial model to estimate how the lack of a mandatory helmet law impacts the cost of health care in the state of Connecticut. The average cost to treat a helmeted rider and a nonhelmeted rider was $3,112 and $5,746 respectively (cost adjusted for year 2014). The total hospital treatment cost in the state of Connecticut from 2003 through 2012 was $73,106,197, with $51,508,804 attributed to nonhelmeted riders and $21,597,393 attributed to helmeted riders. The total Medicaid cost to the state of Connecticut for treating nonhelmeted patients was $18,277,317. This model demonstrates that the lack of a mandatory helmet law increases overall health care costs to the state of Connecticut, and provides a framework by which hospital costs can be reduced to contribute to the economic stability of health care economics in the state.

National mandatory motorcycle helmet laws may save $2.2 billion annually: An inpatient and value of statistical life analysis.

BACKGROUND: While statistics exist regarding the overall rate of fatalities in motorcyclists with and without helmets, a combined inpatient and value of statistical life (VSL) analysis has not previously been reported. METHODS: Statistical data of motorcycle collisions were obtained from the Centers for Disease Control, National Highway Transportation Safety Board, and Governors Highway Safety Association. The VSL estimate was obtained from the 2002 Department of Transportation calculation. Statistics on helmeted versus nonhelmeted motorcyclists, death at the scene, and inpatient death were obtained using the 2010 National Trauma Data Bank. Inpatient costs were obtained from the 2010 National Inpatient Sample. Population estimates were generated using weighted samples, and all costs are reported using 2010 US dollars using the Consumer Price Index. RESULTS: A total of 3,951 fatal motorcycle collisions were reported in 2010, of which 77% of patients died at the scene, 10% in the emergency department, and 13% as inpatients. Thirty-seven percent of all riders did not wear a helmet but accounted for 69% of all deaths. Of those motorcyclists who survived to the hospital, the odds ratio of surviving with a helmet was 1.51 compared with those without a helmet (p < 0.001). Total costs for nonhelmeted motorcyclists were 66% greater at $5.5 billion, compared with $3.3 billion for helmeted motorcyclists (p < 0.001). Direct inpatient costs were 16% greater for helmeted riders ($203,248 vs. $175,006) but led to more than 50% greater VSL generated (absolute benefit, $602,519 per helmeted survivor). CONCLUSION: A cost analysis of inpatient care and indirect costs of motorcycle riders who do not wear helmets leads to nearly $2.2 billion in losses per year, with almost 1.9 times as many deaths compared with helmeted motorcyclists. The per capita cost per fatality is more than $800,000. Institution of a mandatory helmet law could lead to an annual cost savings of almost $2.2 billion. LEVEL OF EVIDENCE: Economic analysis, level III.

The Economic Impact of Helmet Use on Motorcycle Accidents: A Systematic Review and Meta-analysis of the Literature from the Past 20 Years.

OBJECTIVE: The incidence and cost of motorcycle accidents are projected to increase. Motorcycle helmets are accepted as an effective strategy for reducing the morbidity and therefore the cost of motorcycle accidents. Despite this, states have continued to repeal helmet laws in the past 20 years. In addition, variations in the methodologies and outcomes of published reports have contributed to uncertainty regarding the health care dollars saved due to motorcycle helmet use. The purpose of this systematic review and meta-analysis is to clarify the economic impact of motorcycle helmet use. METHODS: Our primary source was Medline. Search terms included "motorcycle," "motorbike," "motorcycle helmet," "head protective devices," and "cost and cost analysis." The review only included articles that were primary studies, written in English, evaluations of periods after 1994, and published in a peer-reviewed journal. Two independent authors extracted data using predefined data fields. Meta-analysis was done using the R-metafor package. RESULTS: Twelve papers met the criteria for inclusion. Meta-analysis demonstrated that nonhelmeted patients required $12,239 more in hospital costs per patient. Nonhelmeted patients also required more postdischarge care and were more likely to use publicly funded insurance. Studies also found lower injury severity and better hospital course in the helmeted population. Study limitations included selection bias, unclear statistical assumptions, lack of precision measures, confounding variables, and lack of standardization to a common year. Meta-analysis demonstrated an I2 of 67%, attributing a significant proportion of outcome variation to study differences. CONCLUSIONS: Motorcycle helmet use reduces morbidity and contributes to significant health care cost savings. Continuing antihelmet legislation will impose a substantial economic burden to the health care system, the government, and the public.

Impact of North Carolina's motorcycle helmet law on hospital admissions and charges for care of traumatic brain injuries.

BACKGROUND North Carolina requires motorcyclists of all ages to wear federally approved safety helmets. The purpose of this article is to estimate the impact of this state law in terms of hospital admissions for traumatic brain injury (TBI) and associated hospital charges. METHODS Hospital admissions of North Carolina motorcyclists with TBIs and associated hospital charges in 2011 were extracted from the North Carolina Hospital Discharge Data system. We estimated hospital admissions and charges for the same year under the counterfactual condition of North Carolina without a universal motorcycle helmet law by using various substitutes (Florida, Pennsylvania, and South Carolina residents treated in North Carolina). RESULTS North Carolina's universal helmet law prevented an estimated 190 to 226 hospital admissions of North Carolina motorcyclists with TBI in 2011. Averted hospital charges to taxpayer-funded sources (ie, government and public charges) were estimated to be between $9.5 million and $11.6 million for 2011, and total averted hospital charges for 2011 were estimated to be between $25.3 million and $31.0 million. LIMITATIONS Cost estimates are limited to inpatients during the initial period of hospital care. This study was unable to capture long-term health care costs and productivity losses incurred by North Carolina's TBI patients and their caregivers. CONCLUSIONS North Carolina's universal motorcycle helmet law generates health and economic benefits for the state and its taxpayers.

Unlicensed motorcycling of high school adolescents in Dehaghan county (Isfahan Province of Iran).

BACKGROUND: Unlicensed motorcycling increases the chances of accidents in adolescents. There are many behavioral and non-behavioral factors involved in adolescents' unlicensed motorcycling which were not addressed in research yet completely. METHODS: The cross-sectional study aimed to determine prevalence and related factors of unlicensed motorcycling on 500 unlicensed male high school adolescents in Dehaghan, who entered in the study by census. Demographic and motorcycling information were collected via self-report questionnaire, and its content validity was approved by a panel of experts. The statistical analyses of the data included Pearson Correlation Coefficient, chi-square, independent samples t-test and ANOVA with Tukey post hoc test. RESULTS: The prevalence of unlicensed motorcycling among participants was 74.2% and mean age at first motorcycling experience was 11.97±1.97 years ranged from 8 to 17. Of the motorcyclist participants, 59.6% owned their personal motorcycle. Most motorcycle passengers (62.8%) were adolescent's friends, and the most frequently expressed reason for use of motorcycle was fun and entertainment (54.2%). Age at first motorcycling experience was lower among rural adolescents than urban adolescents. However, unlicensed motorcycling was more prevalent among urban adolescents than rural ones. The relationship between living status, father's job, mother's job and age at first motorcycling experience was insignificant (P>0.05). However, mean age at first motorcycling experience among students of humanities, technical disciplines, and general first year was lower than that among students of natural sciences and math. CONCLUSION: High prevalence of unlicensed motorcycling and significant role of family and social environments on adolescents' high-risk motorcycling without license, is indicative of the need for interventions at all levels of peers, family, and schools and also establishing new driving regulations in Iran.

Costs of non-helmeted motorcycle riding in Connecticut.

Motorcycle-related head injuries and fatalities are a serious public health concern that can be reduced with helmet use. Caring for crash victims places additional economic stress on the healthcare system. The current Connecticut motorcycle helmet law does not require all motorcyclists to wear helmets. Universal motorcycle helmet laws increase helmet use. Efforts to increase helmet use through education and legislation should be considered for review, given the number of deaths and injuries that could be prevented.

Repeal of the Michigan helmet law: early clinical impacts.

BACKGROUND: Michigan repealed a 35-year mandatory helmet law on April 13, 2012. We examined the early clinical impacts at a level 1 trauma center in West Michigan. METHODS: Retrospective cohort study comparing outcomes among motorcycle crash victims in a 7-month period before and after the helmet law repeal. RESULTS: One hundred ninety-two patients were included. After the repeal, nonhelmeted motorcyclists rose from 7% to 29% (P < .01). There was no difference in mortality rate after admission; however, crash scene fatalities increased significantly. Intensive care unit length of stay, mechanical ventilation time, and cost of stay were also higher in the nonhelmeted cohort (P < .05). CONCLUSIONS: Our study highlights the negative ramifications of repealing a mandatory helmet law. Motorcyclists not wearing helmets increased significantly in a short period of time. Nonhelmeted motorcyclists more frequently died on the scene, spent more time in the intensive care unit, required longer ventilator support, and had higher medical costs.

The use of non-standard motorcycle helmets in low- and middle-income countries: a multicentre study.

BACKGROUND: The use of non-standard motorcycle helmets has the potential to undermine multinational efforts aimed at reducing the burden of road traffic injuries associated with motorcycle crashes. However, little is known about the prevalence or factors associated with their use. METHODS: Collaborating institutions in nine low- and middle-income countries undertook cross-sectional surveys, markets surveys, and reviewed legislation and enforcement practices around non-standard helmets. FINDINGS: 5563 helmet-wearing motorcyclists were observed; 54% of the helmets did not appear to have a marker/sticker indicating that the helmet met required standards and interviewers judged that 49% of the helmets were likely to be non-standard helmets. 5088 (91%) of the motorcyclists agreed to be interviewed; those who had spent less than US$10 on their helmet were found to be at the greatest risk of wearing a non-standard helmet. Data were collected across 126 different retail outlets; across all countries, regardless of outlet type, standard helmets were generally 2-3 times more expensive than non-standard helmets. While seven of the nine countries had legislation prohibiting the use of non-standard helmets, only four had legislation prohibiting their manufacture or sale and only three had legislation prohibiting their import. Enforcement of any legislation appeared to be minimal. INTERPRETATION: Our findings suggest that the widespread use of non-standard helmets in low- and middle-income countries may limit the potential gains of helmet use programmes. Strategies aimed at reducing the costs of standard helmets, combined with both legislation and enforcement, will be required to maximise the effects of existing campaigns.