Inter-rater reliability of the APD, SFU and UTD grading systems in fetal sonography and MRI

INTRODUCTION

Antenatal hydronephrosis (ANH) is frequently detected on screening obstetric ultrasonography. Common ANH grading systems include the anterior-posterior diameter (APD) and the Society for Fetal Urology (SFU) grading system. Recent developments in the management of ANH include the use of fetal magnetic resonance imaging (MRI), and a new grading system - Urinary Tract Dilation (UTD). This study reviewed patients who underwent fetal MRI and ultrasound, and compared the grading systems across these imaging modalities.

MATERIALS AND METHODS

Patients who underwent paired fetal MRI and ultrasound studies between January 2012 and January 2014 were included. Two pediatric urologists and a pediatric radiologist reviewed the studies. Data collected included APD, SFU grade, and UTD grade. Fleiss' kappa statistic determined the inter-rater reliability (IRR) of the SFU and UTD grading within each imaging modality. Intra-class correlation assessed the consistency of the APD measurements.

RESULTS

Forty-seven patients and 88 renal units were evaluated. Median gestational age was 22 weeks. Kappa values of the SFU grading system indicated fair IRR for ultrasound imaging and moderate IRR for MRI imaging, while the UTD grading system reached moderate IRR for both. The IRR of the SFU grading system was improved with the use of MRI, while the UTD grading system was no different. The APD intraclass correlation coefficient improved significantly when measured by MRI. As the ultrasound SFU grade increased, the odds of the MRI SFU grade being scored higher increased by a factor of 3.7. There was no difference between ultrasound and MRI when using the UTD grading system.

DISCUSSION

This study was the first to assess the UTD system in a cohort of patients who underwent paired ultrasound and MRI studies. The results suggested that the UTD system might improve IRR, compared with the SFU system. The use of fetal MRI may improve the IRR of the SFU grading system. It also found that the proportion of SFU grades was affected by the imaging modality, raising the possibility that MRI 'overcalls' the SFU grade, compared with ultrasound. This difference was not observed using the UTD grading system. The most important limitation was the selection bias favoring complex pathology with severe ANH diagnosed at an early gestational age.

CONCLUSIONS

In this unique cohort, the UTD system improved IRR when compared to the SFU grading system. Fetal MRI improved the IRR of the SFU grading system, and improved the APD intraclass correlation. The SFU grading was likely to be higher when assessed by MRI vs ultrasound, but the UTD grade was not affected by the imaging modality.

How do I do it: Continuous local anesthetic infusion for children with spinal dysraphism undergoing major reconstruction of the lower urinary tract

Postoperative pain control is a fundamental aspect of contemporary pediatric surgery. While many options for analgesia are available to the general patient population, choices are limited for individuals with spinal dysraphism who undergo major urologic procedures. Continuous infusion of local anesthetics has been shown to improve postoperative pain scores and decreases the need for systemic analgesia. We present our technique for continuous local anesthetic infusion utilizing readily available equipment with limited additional cost.

Injury to recreational and professional cricket players: circumstances, type and potential for intervention

This paper describes injury (circumstances and type) experienced by sub-populations at all levels of cricket and, where possible, the type of protective equipment used. The sample differs to that generally examined in the literature in that it is not restricted to evaluation of elite and professional players only. Over a 6-year period (2000-2005), 498 cases were identified. The average age of injury was 27 years and 86% of those injured were male. The population incidence rate was 2.3 per 100,000 per year, and participation incidence rate 39 per 100,000 per year. Over all age groups upper limb (36%) and lower limb (31%) were most commonly injured. Fracture was the main type of injury. Differences among age groups were identified. Children (<10 years) most commonly suffered head injury (contact with the bat); 10-19 year olds, head, upper and lower limb injury (in similar proportions) generally from contact with bat/ball; those over 20 years mainly had upper and lower limb injuries. Contact with the bat/ball was the dominant mechanism of injury for those under 50 years of age while overexertion, strenuous or repetitive movements, slips and falls were the mechanisms for those over 50. The large number of head injuries to children is of concern and both these, and the substantial number of injuries to the hand/phalanges (63% of all upper limb injuries), are important targets for injury prevention. The difference in injury patterns between children and adults is indicative of a need to develop, and use, different types of PPE at different skill/age levels.

An evaluation of mouthguard requirements and dental injuries in New Zealand rugby union

OBJECTIVES

To document the effects of compulsory mouthguard wearing on rugby related dental injury claims made to ACC, the administrator of New Zealand's accident compensation scheme.

METHODS

An ecological study was conducted. Estimates of mouthguard wearing rates were available from prospective studies conducted in 1993, 2002, and 2003. Rugby related dental injury claims were available for the period 1995-2003. Player numbers were available from 1998. Mouthguard wearing was made compulsory during match play for rugby players at under 19 level and below at the beginning of the 1997 season, and for all grades of domestic rugby at the beginning of the 1998 season. Greater powers of enforcement were provided to referees at the beginning of the 2003 season.

RESULTS

The self reported rate of mouthguard use was 67% of player-weeks in 1993 and 93% in 2003. A total of 2644 claims was reported in 1995. There was a 43% (90% confidence interval 39% to 46%) reduction in dental claims from 1995 to 2003. On the reasonable assumption that the number of players and player-matches remained constant throughout the study period, the relative rate of injury claims for non-wearers versus wearers was 4.6 (90% confidence interval 3.8 to 5.6). The cumulative savings in claim costs compared with the cost per year if claim numbers had remained constant from 1995 is 1.87 million NZD.

CONCLUSION

Although ecological studies have acknowledged weaknesses, the findings provide evidence that mouthguard use is a simple and effective injury prevention strategy for rugby players. The use of mouthguards for all players in both matches and contact practice situations is strongly recommended.

Playing conditions, player preparation and rugby injury: a case-control study

This paper investigates the effect of player preparation, ground conditions and weather conditions upon the injury risk for Rugby Union players. A population-based case-control study was performed using a sample (n= 1043) of New Zealand Rugby Union players aged 16 y and above. Details concerning game preparation (warm-up and usual position), and ground and weather conditions (precipitation, wind and temperature) were obtained from the players. If players were injured during the season (n= 624) they were asked to provide details about the game in which they were last injured. Uninjured players (n= 419) provided details about the last game in which they played. Injuries were more likely to occur when games were played on hard grounds or in calm or warm conditions. Playing out of position and the duration of warming up did not significantly alter the risk of injury. When player preparation, ground and weather conditions, grade, age, playing position and rugby experience were simultaneously controlled for, hard ground and the absence of wind were associated with increased risk. The influence of these factors may be indirect, through adaptation to the conditions in which a game is played.

Tackling Rugby injury: lessons learned from the implementation of a five-year sports injury prevention program

Rugby Union football is a very popular sport in New Zealand but of all the major sports played in that country, it has the highest reported incidence of injury. In 1995, a national rugby injury prevention program was instigated to address this problem. Known as Tackling Rugby Injury, this multifaceted program was implemented over a five-year period. The program was based on the results of a prospective cohort study of rugby injury, known as the Rugby Injury and Performance Project (RIPP), and was organised around seven themes, five relating to the prevention of injury: coaching, fitness, injury management, tackling, and foul play, and two relating to the implementation and evaluation of the program. The purpose of this paper is to describe the lessons learned from the implementation of Tackling Rugby Injury. Qualitative research methods were used to describe the process of implementation, including informant interviews, participant observation, and the scrutiny of written, visual and archival material. Among the lessons learned were the importance of basing injury prevention strategies on scientific evidence rather than popular belief, the difficulty in implementing complex interventions, the advantages of a formal agreement between partners in the implementation of a program, the central role played by coaches in promoting injury prevention strategies, and the value of describing the process of implementation as well as monitoring injury outcomes and changes in knowledge, attitudes and behaviour. It is hoped that other sports wishing to develop injury prevention programs can learn from this experience.

Examining child restraint use and barriers to their use: lessons from a pilot study

OBJECTIVE

To determine the suitability of four research methods to measure the rate of child restraint device (CRD) use and incorrect use in New Zealand and obtain data on barriers to CRD use.

DESIGN AND SETTING

To assess the rates of CRD use among vehicles carrying children 8 years of age and under, two methods were piloted-namely, an unobtrusive observational survey and a short interview and close inspection. A self administered questionnaire and focus group interviews were also piloted to assess CRD use, reasons for use and non-use, and to obtain information on barriers to their use. Respondents to all methods except the focus groups were approached in supermarket car park sites at randomly selected times. Focus groups were established with parents identified through early childhood organisations. All methods were assessed on criteria related to efficiency, representativeness, and ability to obtain the necessary data.

RESULTS

The observational survey provided a simple method for identifying rates of CRD use, while the self administered questionnaire obtained data on demographic characteristics and reported the installation and use/non-use of CRDs. The interview/inspection addressed all the questions of both the above methods and enabled incorrect CRD use to be examined. The focus groups provided the most meaningful information of all methods on barriers to CRD use.

DISCUSSION

and conclusion: Advantages and limitations of these methods are discussed and some refinements of the original instruments are proposed. The interview/inspection and focus group methods were identified as being more appropriate for efficiently obtaining reliable data on CRD use and identification of barriers to CRD use.

Rugby headgear study

A two year randomised controlled trial of headgear in Rugby Union football is being conducted in Sydney, Australia. This paper gives an overview of this study in progress and presents results related to the development and laboratory performance of the headgear. The study commenced in 2002. Participants recruited to the study are in the under 13, 15, school open (U18) and colts age groups. There are three study arms: control, IRB-approved headgear, and modified headgear. The IRB approved headgear is a popular model in rugby, the Canterbury Honeycomb model manufactured by BodyArmour in New Zealand. The dimensions of this model were altered by increasing foam density and thickness to produce the modified headgear. In impact energy attenuation tests of 15 and 20 Joules onto a flat anvil, the modified headgear demonstrated average maximum headform accelerations of 23% and 33% of the standard model, respectively. Whether or not this improvement translates into reductions in injury will be determined by a comparison of the rates and severities of head injuries across study arms. Furthermore, these dimensional changes may not be acceptable to rugby players. Player attitudes towards safety and the use of protective clothing, injury history, experience and on-field behaviour will be examined via structured pre- and end of season surveys and analysis of match video.

Biomechanical analysis of arm fracture in obese boys

OBJECTIVE

To determine the role of the biomechanical factors of force of impact, bone strength, fall height and surface stiffness on the risk of forearm fracture in obese children compared to non-obese children.

METHODOLOGY

Anthropometric and dual-energy X-ray absorptiometry bone density data from 50 boys (25 obese pair-matched with 25 non-obese subjects) aged 4-17 years were entered into a rheological-stochastic simulation model of arm impact.

RESULTS

Obese children were shown to be at 1.7 times greater risk of fracture compared to non-obese children. Lower fall heights and softer impact surfaces were found not to reduce the relative risk of fracture between obese and non-obese children.

CONCLUSIONS

Environmental modifications are unlikely to lower the risk of arm fracture in obese children to the same levels experienced by non-obese children. The best option available for obese children to reduce fracture risk is to take steps to attain a healthy bodyweight.

Injury prevention in sport: not yet part of the game?

BACKGROUND

There is a saying in sport that "injury is just part of the game". In other words, injury in sport is seen as inevitable.

OBJECTIVE

To examine progress toward reaching the contrary position that "injury prevention is just part of the game".

METHODS

The four steps of van Mechelen's "sequence of prevention" model provide a structure for examining progress.

RESULTS

What is known about the size of the problem (step 1)? Most is known about more serious injuries and about injuries in élite and professional sport. Least is known about less serious injuries, injury in community level and amateur sport, and injury occurring in recreational activities. What is known about risk factors (step 2)? Despite calls for analytic studies since the early 1980s, few such studies have been reported in the literature. What is known about the effectiveness of preventive measures (step 3)? Few randomized controlled trials have been reported in the literature. Are there systems in place to monitor sports injury (step 4)? Examples are given of systems in North America, Europe, and Australasia.

CONCLUSIONS

With a few exceptions, progress has not gone beyond step 1 in van Mechelen's model. Challenges for the future include: deciding where research efforts should be placed, standardization of definitions and methods of data collection and reporting, identification of risk factors and mechanisms of injury, and the evaluation of interventions. Finally, if the field of sports injury prevention is to advance, multidisciplinary collaboration will be required, along with the involvement of the sports community.

Infant-furniture-related injuries among preschool children in New Zealand, 1987-1996

OBJECTIVE

To describe the epidemiology of infant-furniture-related fatalities and hospitalizations in New Zealand, for children aged 0-4 years.

METHODS

Infant-furniture-related deaths and hospitalizations were selected from the New Zealand Health Information Service databases for the 10-year period 1987-1996. Intentional injuries were excluded.

RESULTS

Forty-three fatalities were identified. Twenty-two fatalities (51%) occurred in cots, while 13 (30%) occurred in beds. Other products involved were prams, push chairs, high chairs, car seats, portable cots and walkers. A total of 1679 infants were hospitalized through infant-furniture-related injuries. Increasing trends in hospitalizations for baby walkers, beds and bunks were observed.

CONCLUSIONS

On average, four infants die each year from injuries related to infant furniture, and hospitalizations from injuries associated with infant furniture use are increasing. Mandatory standards are one measure to reduce these numbers, but education is also necessary.

Adolescent injury morbidity in New Zealand, 1987-96

OBJECTIVES

Adolescents are over-represented in injury statistics. New Zealand is privileged in having a hospital discharge database allowing for analysis of non-fatal injury data at a national level. An epidemiological description of adolescent injury morbidity is provided and options for prevention are discussed.

METHOD

People aged 15-19 years admitted to hospital for their injuries in the period 1 987-96 were identified from the New Zealand Health Information Service morbidity data files. The manner, causes, and nature of injury were examined. Injury prevention strategies were reviewed.

RESULTS

The incidence of hospitalised injury was 1,886 per 100,000 person years. The victims were male (70%). The leading causes of injury were road traffic crashes, sports injuries, and self poisoning. The most common injury diagnoses were head injuries (29%) and limb fractures (21%). Road traffic crashes produced the highest proportion of serious injuries.

CONCLUSIONS

Road traffic crashes, sports injuries, and self inflicted poisoning, stood out as areas with the greatest potential for reducing the burden of injury in late adolescence. Graduated driver licensing shows promise as an injury prevention measure but remains inadequately implemented. Policies to reduce self inflicted poisoning are of unknown efficacy, and evidence is awaited on the effectiveness of measures to reduce injury in sport.

Shopping trolley-related injuries to children in New Zealand, 1988-97

OBJECTIVE

To describe the epidemiology of shopping trolley related injuries (fatalities and hospitalizations) to children in New Zealand prior to the introduction of a voluntary standard for shopping trolleys.

METHODOLOGY

To identify cases, a key word search was conducted of national mortality and hospitalization databases for the years 1988-97. Cases were limited to children under 15 years of age.

RESULTS

For the 10 year period investigated, 282 hospitalizations and no fatalities were identified. A significant increasing trend for hospitalizations was detected (chi2 = 17.6, 1 d.f.; P < 0.001). Ninety-two per cent of children hospitalized were aged under 5 years and two-thirds were aged 2 years or younger. Ninety per cent of injuries resulted from falls from trolleys, 84% of injuries were to the head or face and 22% were rated serious (AIS-3) on the Abbreviated Injury Scale.

CONCLUSIONS

The incidence of injuries associated with shopping trolleys increased between 1988 and 1997. Following the introduction of a voluntary standard for shopping trolleys in 1999, which included specifications for child harnesses, trends in injury should be monitored.

Use of protective equipment in a cohort of rugby players

PURPOSE

To describe the level of usage of protective devices and equipment in a cohort of New Zealand rugby players.

METHODS

Male and female players (N = 327) from a range of competitive grades were followed over the course of the season. Participants were interviewed weekly about their participation in rugby and use of protective equipment. The main outcome measure was percentage of all player-weeks of follow-up for which each equipment item was used.

RESULTS

Mouthguards, the most commonly used equipment item, were worn for 64.9% of player-weeks. Mouthguard usage ranged from 55.0% of player-weeks in Schoolgirls grade to 72.9% of player-weeks in Senior A competition. The next most common item was taping of body joints (23.7% of player-weeks). The sites most commonly taped were the ankle, knee, and hand. Overall usage for the other protective equipment items studied (shin guards, padded headgear, head tape, support sleeves, and grease) was below 15%. In general, forwards had higher usage of protective equipment than backs, and male players had higher usage than female players. The most common self-reported reasons for using protective equipment were to prevent injury and because of a past injury. Players exhibited considerable week-to-week variation in their usage of protective equipment.

CONCLUSIONS

In general, equipment usage was highest in those at greatest risk of injury, namely, forwards, male players, and the senior grades. The high voluntary use of mouthguards is encouraging and indicative of a base of player support for their role in this sport.

The New Zealand rugby injury and performance project. VI. A prospective cohort study of risk factors for injury in rugby union football

OBJECTIVES

Although the nature of rugby injury has been well documented, little is known about key risk factors. A prospective cohort study was undertaken to examine the association between potential risk factors and injury risk, measured both as an injury incidence rate and as a proportion of the playing season missed. The latter measure incorporates a measure of injury severity.

METHODS

A cohort of 258 male players (mean (SD) age 20.6 (3.7) years) were followed through a full competitive season. At a preseason assessment, basic characteristics, health and lifestyle patterns, playing experience, injury experience, training patterns, and anthropometric characteristics were recorded, and then a battery of fitness tests were carried out.

RESULTS

A multiple regression model identified grade and previous injury experience as risk factors for in season injury, measured as an injury incidence rate. A second model identified previous injury experience, hours of strenuous physical activity a week, playing position, cigarette smoking status, body mass index, years of rugby participation, stress, aerobic and anaerobic performance, and number of push ups as risk factors for in season injury, measured as proportion of season missed.

CONCLUSIONS

The findings emphasise the importance of previous injury as a predictor of injury incidence and of missing play. They also show the importance of considering both the incidence rate and severity of injury when identifying risk factors for injury in sport.

Child injury morbidity in New Zealand, 1987-1996

OBJECTIVES

New Zealand is one of a small number of countries that has a national hospital discharge database. The aim of this study was to use these data to provide an epidemiological description of child injury morbidity and to discuss options for prevention.

METHODOLOGY

Using national data, all public hospital admissions for the fiscal year 1995/6 were identified and grouped according to cause. This allowed identification of all children (0-14 years) hospitalized for injury in the period 1987-1996. Causes of injury, diagnoses and injury severity were examined in four age groups.

RESULTS

Injury was the second leading cause of public hospital admissions. Children were hospitalized with injury at the rate of 1333 per 100 000 person-years. The victims were predominantly male (61%). In all age groups, falls were the leading cause of morbidity. 'Striking events', motor vehicle traffic crashes and poisoning were also major contributors to the child injury toll. The commonest injury diagnosis was a fracture of the upper limb (25%), followed by intracranial injury (18%).

CONCLUSIONS

The leading causes of injury morbidity were noted to differ from previously reported leading causes of injury mortality. Review of the data in light of research literature suggests the need for policy changes to make alternatives to motor vehicle transportation safer and to encourage increased use of child restraints in order to reduce road traffic trauma. Legislation requiring child-resistant packaging for all toxic medications and household products is necessary to reduce rates of child poisoning. Further research is required on policies concerning playground equipment heights and surfacing requirements, and on interventions for hot water scalds.

Compliance of Dunedin school playground equipment with the New Zealand playground standard

OBJECTIVE

Injuries resulting from falls from playground equipment are a public health concern in New Zealand. Like many other countries, New Zealand has a safety standard aimed at reducing the incidence and severity of these injuries by limiting the height from which children can fall from playground equipment and requiring the provision of impact-absorbing surfaces beneath equipment from which falls are possible. The purpose of this study was to examine progress towards achieving compliance with these requirements in Dunedin school playgrounds.

METHODS

Sixty-two schools were audited over the summer of 1997/98 and information recorded on equipment type, maximum fall height, surface type, and depth of loose-fill surface materials. Comparisons were made with audits conducted in 1989 and 1981.

RESULTS

Substantial increases in the amount of playground equipment and in the provision of impact-absorbing surfaces were observed. A small increase in compliance with the requirement that the maximum fall height of equipment not exceed 2.5 metres was also observed.

CONCLUSIONS

Any gains in safety achieved through increased compliance with the height and surface requirements of the New Zealand Standard have been counteracted by the substantial increase in the amount of equipment available in playgrounds.

IMPLICATIONS

A more drastic measure is needed to achieve a meaningful reduction in the incidence of injury following falls from playground equipment.

Child injury mortality in New Zealand 1986-95

OBJECTIVES

Injury has been described as 'the last major plague of the young'. We provide an epidemiological description of injury, as a leading cause of death in New Zealand, and identify options for prevention.

METHODS

We identified all deaths due to any cause for the period 1986-95 from the national data and calculated the potential years of life lost for each death. For the same period, we identified all injury deaths for children aged 0-14 years. Causes of injury were examined in four age groups.

RESULTS

In the population as a whole, injury was the fourth leading cause of death and the leading cause of potential years of life lost. Injury killed children at the rate of 16.8 per 100,000 person-years. The victims were predominantly male (62%) and 52% were under 5 years of age. In infancy (<1 year of age), suffocation was the leading cause of injury mortality. From 1 to 14 years of age, motor vehicle traffic incidents were the leading cause of mortality.

CONCLUSIONS

Motor vehicle traffic incidents, drowning, suffocation and suicide stood out as areas with the greatest potential for reducing child injury mortality. A number of existing prevention strategies show promise (e.g. child restraints), others are inadequately implemented (e.g. swimming pool fencing) or are of unknown efficacy (e.g. government suicide prevention policies). Strategies to reduce infant suffocation and child non-traffic pedestrian deaths remain to be developed and tested.

Temporal patterns of injury during a rugby season

The aim of this study was to describe temporal patterns in the frequency, nature and circumstances of injuries occurring among a cohort of 356 rugby players during a club rugby season in New Zealand. It was found that the rate of injury in games decreased significantly over time in both males and females. The reduction in injury rate over the season was more pronounced in some grades, but no differences were found when examined by gender. playing position, age, ethnicity or by health and fitness types. Trends in injury rate were consistent over the rugby season and did not appear to be the result of a bias involving under-reporting of end-of-season injuries. The types and severity of injury remained relatively constant, but the proportion of injuries occurring in back play fell significantly over the season and injuries were more likely to occur in the trunk body region as the season progressed. This study supported the hypothesis that higher rates of injury occur at the start of the rugby season and decrease over the course of the season. This reduction is consistent over time and across player types, and is not attributable either to decreasing injury severity or to increasing player fitness.

The incidence, nature, and severity of injuries in New Zealand civil aviation

BACKGROUND

Strategies to improve aviation safety can be directed at the pre-crash, in-crash, or post-crash phases of aircraft crashes. For resources to be made available for in-crash interventions, and for these to be well designed, it is necessary in the first instance to have a detailed understanding of the injuries sustained in crashes. The purpose of this study was to describe the incidence, nature, and severity of injuries sustained in aircraft crashes and other related events in civil aviation in New Zealand.

METHODS

National injury databases were searched for fatalities and hospitalizations sustained in aircraft crashes and related events, and cases were linked with Civil Aviation Authority accident records to identify the aircraft involved. Rates were based on estimates of total hours flown by active pilots.

RESULTS

There were 104 fatalities identified for the period 1988-1992, giving a rate of 2.57 per 100,000 flight hours. There were 120 hospitalizations identified for the period 1988-1993, giving a rate of 2.45 per 100,000 flight hours. Most fatalities involved injury to multiple body regions, with at least one injury being sufficient in itself to cause death in 48% of cases. For hospitalizations, the lower extremities (23%), spine (20%), and head and face (18%) were the body regions most commonly injured, with fractures being predominant. While the majority of fatalities and hospitalizations occurred in fixed- and rotary-wing aircraft, the highest rates were for microlight and home-built aircraft.

CONCLUSIONS

Different patterns of injury were evident for fixed- and rotary-wing aircraft. Reasons for these are suggested. Future research will seek to determine the relative risk associated with potentially modifiable risk factors.

Coding the circumstances of injury: ICD-10 a step forward or backwards?

The International Classification of Diseases (ICD) E codes are the most widely used coding frame for categorising the circumstances of injury and poisoning. In 1992 major revisions to the E codes were released. The aim of this paper was to consider whether the changes made are a step forward or backwards in terms of facilitating injury prevention. The approach taken was to reflect on some former injury prevention research needs and the challenges they presented using data coded according to ICD-9, and then to consider how, if at all, ICD-10 has addressed these difficulties. As with ICD-9, there are essentially two axes associated with each cause: intent and mechanism of injury, and these are captured by one code. This approach can have the unintended effect of hiding the significance of some mechanisms of injury. While there have been significant improvements in some areas, such as falls, in others, such as injuries due to firearms, ICD-10 has taken a step backward. In addition the failure to produce mutually exclusive codes presents problems for determining the incidence of downing events. A welcome addition are "optional" activity codes which enable the identification of work related and sport related injury for the first time. Nevertheless, the limited range of codes and absence of coding guides limits their utility. The revised place of occurrence codes do not represent a significant improvement on ICD-9 in that they are limited to 10, they are not mutually exclusive, and they do not adequately cover a range of specific places of occurrence. In summary, relative to its predecessor, ICD-10 represents a significant improvement in many areas. Unfortunately, it still falls far short of the mark for many injury prevention needs.

Achieving compliance with pool fencing legislation in New Zealand: a survey of regulatory authorities

OBJECTIVES

To identify the status of compliance and enforcement of New Zealand's Fencing of Swimming Pools Act (FOSP Act), 10 years after its introduction, and to identify methods for improving both compliance with the act and the process of enforcement.

METHODS

A postal questionnaire was sent to all 74 authorities in New Zealand in which they were asked questions about their enforcement of the FOSP Act. Semistructured telephone interviews were conducted with 12 authorities to supplement the data obtained in the postal survey.

RESULTS

Based on responses to the survey, it was estimated that there are over 59,000 domestic swimming pools in New Zealand, giving rates of 46 pools/1000 dwellings and 16 pools/1000 persons. The authorities reported that 44% of pools complied with the act, and a further 4% had been granted exemptions. Nineteen per cent of pools were reported to not comply with the act, and the compliance status of a further 33% was not known, or not stated by the authority. Only 9% of authorities had procedures for locating and inspecting pools, while 28% had a programme of reinspection to ensure that pools continued to comply. Pool owner resistance was considered to be the main difficulty with enforcing the act, and nearly half of the authorities believed publicity or education was needed to overcome these barriers. Fifty two per cent of authorities had publicized the act during the 12 months preceding the survey.

CONCLUSIONS

Due to ambiguities within the legislation, and differing levels of commitment by authorities to locate pools and monitor compliance, compliance with the FOSP Act is not consistent nationally. If the act were less ambiguous, there would be greater consistency and more enforcement.

The nature and circumstances of tackle injuries in rugby union

This study describes the nature and circumstances of injury occurring in rugby union tackles (33% of 569 injury events) using data from the Rugby Injury and Performance Project (RIPP) and provides supplementary information on the nature of tackles involving injury from analysis of videotape of tackle injury events. The most common tackle injuries in the RIPP data were sprains/strains (41%) followed by haematomas/bruising (26%). The most frequently injured body sites were the head/neck/face (22%) and the knee (17%). The ball carrier and tackler were injured in tackles in similar proportions in both RIPP and New Zealand Rugby Football Union (NZRFU) video tackle incidents. Both players were most often in motion in the tackle at the time of injury with approximately 70% of injuries occurring when the injured player was running or diving/falling to the ground. Tackle injury was most often caused by impact with another player rather than impact with the ground. The use of protective padding may reduce the risk of impact injury. The majority of tackle injuries were associated with stopping tackles to the trunk which were from the front (63%), rather than from the side or behind. Thus consideration should be given to coaching strategies or to rule changes which reduce the likelihood or prohibit front-on tackles.

An intervention to reduce playground equipment hazards

OBJECTIVES

A community intervention trial was carried out to evaluate the relative effectiveness of two methods of reducing playground hazards in schools. The study hypotheses were: (1) a health promotion programme addressing barriers to implementing the New Zealand Playground Safety Standard will reduce playground hazards and (2) the intervention programme will be more successful than providing information alone.

METHODS

Twenty four schools in Wellington, New Zealand were randomly allocated into two groups of 12 and their playgrounds audited for hazards. After the audit, the intervention group received a health promotion programme consisting of information about the hazards, an engineer's report, regular contact and encouragement to act on the report, and assistance in obtaining funding. The control group only received information about hazards in their playground.

RESULTS

After 19 months, there was a significant fall in hazards in the intervention schools compared with the control schools (Mann-Whitney U test, p = 0.027). No intervention schools had increased hazards and eight out of 12 had reduced them by at least three. In contrast, only two of the control schools had reduced their hazards by this amount, with three others increasing their hazards in that time.

CONCLUSIONS

It is concluded that working intensively with schools to overcome barriers to upgrading playground equipment can lead to a reduction in hazards, and that this form of intensive intervention is more effective than providing information alone.

Evaluating Tackling Rugby Injury: the pilot phase for monitoring injury

OBJECTIVE

To assess the suitability of two previously unused data sources for monitoring rugby injury throughout New Zealand.

METHOD

Interviews were conducted with respondents sampled from players registered with the Rugby Football Unions (RFUs) and players claiming for rugby injuries from the Accident Rehabilitation and Compensation Insurance Corporation (ACC) in Auckland and Dunedin.

RESULTS

Of the 500 RFU players sampled, 63% were interviewed and of these 39 (12%) had been injured playing rugby union. Of the 456 ACC claimants sampled, 66% were interviewed and 265 (88%) had been injured playing rugby union.

CONCLUSION

Identifying injured players through ACC claims was more efficient, both procedurally and because a smaller sample size was required to detect changes in incidence.

IMPLICATIONS

With no routine surveillance of sports injury being undertaken, recording sporting codes in national injury surveillance systems would assist the monitoring of sports injury.

The New Zealand Rugby Injury and Performance Project: V. Epidemiology of a season of rugby injury

OBJECTIVE

To describe the incidence, nature, and circumstances of injury experienced by a cohort of rugby union players during a full competitive club season.

METHODS

A prospective cohort study followed up 356 male and female rugby players throughout the 1993 competitive club season. Players were interviewed by telephone each week to obtain information on the amount of rugby played and the injury experienced.

RESULTS

Detailed information was collected for 4403 player-games and 8653 player-practices. A total of 671 injury events were reported, of which 569 were rugby related. The injury rate for games was higher than that for practices (rate ratio 8.3). At 10.9 injuries per 100 player-games, males had a higher rate of injury than females at 6.1 injuries per 100 player-games (p<0.001). Injury rates varied by position, with male locks (13.0 injuries per 100 player-games) and female inside backs (12.3 injuries per 100 player-games) having the highest rate in their respective sexes. The lower limb was the body region most often injured in games (42.5%) and practices (58.4%). Sprains/strains were the most common type of injury in games (46.7%) and practices (76.1%). In games the tackle was the phase of play in which the most injuries occurred (40%), followed by rucks (17%) and mauls (12%). Thirteen per cent of game injury events were the result of foul play.

CONCLUSIONS

Rugby injury was common among the study subjects and varied according to grade and gender. Identifying the causes of injuries in the tackle, lower limb injuries, and dealing with the issue of foul play are priority areas for the prevention of rugby injury.

Mouthguards. Protection for the mouth in rugby union

The mouthguard is a resilient device or appliance which is placed inside the mouth to protect against injuries to the teeth, lacerations to the mouth and fractures and dislocations of the jaw. There is clear support in the scientific literature for the use of mouthguards in contact sports such as rugby. Moreover, there is evidence that mouthguards are effective in protecting against concussion and injuries to the cervical spine. There is a high level of acceptance of mouthguards by players and an increasing number are regularly wearing mouthguards. This is especially true among the elite players, but acceptance and wearing rates are moderately high among club players as well. There is strong support among players and researchers for mouthguard wearing to be made compulsory. It is generally recommended that: (i) mouthguards be worn during both practice sessions and games; (ii) the habit of wearing a mouthguard begins at an early age; (iii) mouthguards be regularly replaced while children are still growing; and (iv) adult players replace their mouthguards at least every 2 years. The selection of a mouthguard will depend on a number of factors including the age of the individual, effectiveness and cost. The type I (stock), or 'off-the-shelf', mouthguards are considered inferior when compared with the other available types, and their use is discouraged. Type II (mouth-formed) mouthguards come in 2 forms, the shell-liner version and the popular thermoplastic 'boil and bite' version. While the effectiveness of the shell-liner mouthguard was examined in one experimental study, no such research has been reported for the thermoplastic mouthguard. Type III (custom-fabricated) mouthguards are recommended for players playing in the more vulnerable positions and in the higher grades. Most experimental studies in which the effectiveness of mouthguards has been demonstrated have involved type III mouthguards.

Continuity and change in sporting and leisure time physical activities during adolescence

OBJECTIVES

To map the pattern of involvement in physical activities by adolescents at ages 15 and 18 years.

METHODS

Data from a longitudinal cohort study were used. Participants in the Dunedin Multidisciplinary Health and Development Study provided information about their sporting and similar physical activities during the 12 months before study assessments at ages 15 and 18 years.

RESULTS

Total participation time at age 18 was 63% of that reported at age 15. Mean participation time for girls decreased from 7.5 hours a week to 4.3 hours a week (p<0.001) whereas for boys it decreased from 11.7 hours a week to 7.8 hours a week (p<0.001). At both ages, boys spent significantly more time in physical activity than girls. More time in physical activity at age 18 was reported by participants who judged their fitness higher than their peers (odds ratio (OR) 1.7: 1.2, 2.5), those who played sport for their school (OR 1.8: 1.3, 2.4), and those reporting very good self assessed health (OR 1.4: 1.0, 1.8) at age 15. The overall median number of activities decreased from seven at age 15 to three at 18. Boys were involved in more activities at age 15 but there was no sex difference at age 18 in the number of different activities reported.

CONCLUSION

Although involvement in school sporting activities and high levels of fitness in mid-adolescence may protect against marked reductions in physical activity in late adolescence, social and organisational factors are also likely to be important. There is a need for innovative approaches to health promotion which will encourage adolescents to maintain higher levels of physical activity after they leave school.

Psychological and social predictors of motorcycle use by young adult males in New Zealand

Motorcycle riding is a significant cause of serious injuries to young males. Little is known about the psychological and social characteristics of these riders, despite such knowledge being potentially important for the targeting of appropriate injury prevention interventions. Using problem-behaviour theory to broadly guide and structure the research, the present study focused on identifying predictors of motorcycle riding. Previous research investigating differences between riders and non-riders has tended to be inconclusive, methodologically limited, and lacking in explicit theoretical foundations. The present research was based on the birth cohort enrolled in the Dunedin Multidisciplinary Health and Development Study (DMHDS), a comprehensive New Zealand longitudinal study of health, development, attitudes, and behaviours. Logistic regression models were built using prior measures of health risk behaviour, other psychological and social factors, and motorcycle riding history as potential predictors of any motorcycle use at the age of 18 years. The strongest predictors were early motorcycle riding, including illegal on-road driving at age 13 (OR 4.0; 95% CI 1.7, 9.1), below average reading skills (OR 2.4; 95% CI 1.3, 4.6) and fighting in a public place at age 15 (OR 2.9; 95% CI 1.2, 6.9). It was of particular interest that this profile tended to fit less well those subgroups of riders with greatest exposure to on-road motorcycle driving. Although based on small numbers, this finding was consistent with earlier cross-sectional research that linked casual and unlicensed driving with less protective motorcycling opinions and behaviours. Some implications for injury prevention and public policies regarding motorcycling are discussed. In particular, stricter enforcement of present licensing regulations and stronger penalties for their violation could help to reduce the number of less responsible riders.

Trampoline injury in New Zealand: emergency care

OBJECTIVE

To examine trampoline related injuries resulting in emergency department attendance.

METHODS

Cases were identified by searching free text descriptions of the circumstances of injury contained in the records of the emergency department of a large city hospital.

RESULTS

114 cases were identified for a 12 month period, giving an incidence rate of 108 per 100,000 population per year (95% confidence interval = 89 to 129) compared with 9.3 hospital admissions per 100,000 population per year (95% confidence interval = 8.3 to 10.4) for a corresponding period reported in earlier research from New Zealand. This suggested that for every one hospital admission there are approximately 12 emergency department attendances. Of the cases, 95% were aged less than 20 years. As for the earlier research, falls from the trampoline to the surrounding surface were the commonest cause of injury. In the present study, sprains and strains were the commonest type of injury (40%), and the body site most frequently involved was the lower limb (46%).

CONCLUSIONS

The findings support the conclusion from earlier research that although existing trampoline standards address many of the issues relating to trampoline safety, the need remains for measures to reduce the impact of falls from the trampoline to the ground surface and to prohibit the use of trampolines as unsupervised "play equipment".

Diastereoselective synthesis of all four isomers of 3-(4-chlorophenyl) glutamic acid: identification of the isomers responsible for the potentiation of L-homocysteic acid-evoked depolarizations in neonatal rat motoneurons

All four isomers of 3-(4-chlorophenyl)glutamic acid (5-8) were prepared by diastereoselective synthesis. Addition of (6S)-(+)-bis-lactim ether 15 to cis-4-chlorocinnamate 12 gave a mixture comprising mainly the (2R,3S)- and (2R,3R)-isomers 5 and 6, respectively (in a ratio of 56:40), while addition of (6R)-(-)-bis-lactim ether 16 to 4-chlorocinnamate 12 gave a mixture comprising mainly the (2S,3R)- and (2S,3S)-isomers 8 and 7, respectively (in a ratio of 56:42). The four stereoisomers (5-8) were therefore conveniently prepared by addition of either 3-lithio-(6S)- or -(6R)-bis-lactim ether (15 or 16, respectively) to 4-chlorocinnamate 12 and separation of the resultant mixtures of diastereoisomers (23-26) by flash silica gel chromatography. The absolute configurations of 6 and 7 were confirmed by X-ray crystallography. Both the (2S,3S)- and (2S,3R)-isomers (7 and 8, respectively) at a concentration of 100 microM significantly potentiated depolarizations induced by 10 microM L-homocysteic acid (L-HCA) (% control +/- sem: 130.4 +/- 3.6, n = 20 and 114.5 +/- 2.4, n = 11, respectively) while the (2R,3S)-isomer 5 significantly reduced L-HCA response amplitude (94.2 +/- 1.4, n = 9) and the (2R,3R)-isomer 6 was inactive. Experiments designed to compare the agonist-potentiating actions of 7 and 8 in the neonatal rat spinal cord with L-trans-pyrrolidine-2,4-dicarboxylic acid, the well-known L-Glu uptake inhibitor, provided additional evidence for the selective enhancement of depolarizations due to L-HCA and not those due to L-Glu. This selective action supports the existence of multiple excitatory amino acid uptake sites.

Rider training, reasons for riding, and the social context of riding among young on-road motorcyclists in New Zealand

Serious injuries to young motorcyclists represent an important public health problem. Little is known about the opinions and behaviours of the young riders at risk. We document the training experiences of young motorcyclists, and their reasons for riding or discontinuing riding, and identify the role models and sources of disapproval of motorcycling. The research was part of a longitudinal study of health, development, attitudes and behaviours of a birth cohort. At age 18 years, cohort members who had ridden a motorcycle during the past year completed a comprehensive questionnaire. Initial riding instruction was rarely received from a qualified instructor but was usually informal, from a male friend or father, and occurred off the road, usually on a farm. The most commonly given reasons for riding were excitement and economy. Most motorcyclists who had ceased riding attributed this to the lack of access to a motorcycle, and few mentioned safety. Mothers were the main source of disapproval. The young riders were not a homogeneous group. More licensed than unlicensed riders said manoeuvrability in traffic and ease of parking were reasons for riding. Licensed motorcyclists had more friends who rode and were more likely than unlicensed riders to have received paternal instruction. Early informal training off the road may establish attitudes and behaviours inappropriate in a traffic context. The main reasons for motorcycling (excitement, economical and manoeuvrable transport, freedom from supervision) and for discontinuing riding (lack of access) indicate motivations that should be considered before implementation of injury prevention interventions.

Height and surfacing as risk factors for injury in falls from playground equipment: a case-control study

OBJECTIVES

Despite the widespread promotion of safety standards no epidemiological studies have adequately evaluated their effectiveness in preventing injury in falls from playground equipment. This study evaluated the effectiveness of the height and surfacing requirements of the New Zealand standard for playgrounds and playground equipment.

SETTING

Early childhood education centres and schools in two major cities in the South Island of New Zealand.

METHODS

Data were collected on 300 children aged 14 years or less who had fallen from playground equipment. Of these, 110 (cases) had sustained injury and received medical attention, while 190 (controls) had not sustained injury requiring medical attention.

RESULTS

Logistic regression models fitted to the data indicated that the risk of injury being sustained in a fall was increased if the equipment failed to comply with the maximum fall height (odds ratio (OR) = 3.0; 95% confidence interval (CI) 0.7 to 13.1), surfacing (OR = 2.3; 95% CI 1.0 to 5.0), or safe fall height (OR = 2.1; 95% CI 1.1 to 4.0) requirements. Falls from heights in excess of 1.5 metres increased the risk of injury 4.1 times that of falls from 1.5 metres or less and it was estimated that a 45% reduction in children attending emergency departments could be achieved if the maximum fall height was lowered to 1.5 metres.

CONCLUSIONS

Although the height and surfacing requirements of the New Zealand standard are effective in preventing injury in falls from playground equipment, consideration should be given to lowering the maximum permissible fall height to 1.5 metres.

The risky and protective motorcycling opinions and behaviours of young on-road motorcyclists in New Zealand

This research documented the frequency of protective and risky motorcycling opinions and behaviours and investigated whether these opinions and behaviours were more frequently expressed by licensed than unlicensed riders and by riders with high rather than low exposure to motorcycling. Areas where there was scope for improvement were identified to help guide the promotion of protective strategies. As part of a broader study of a birth cohort, 217 18 year old motorcyclists were administered a motorcycling computer questionnaire. Evidence of positive protective opinions was found, but there was considerable scope for behavioural improvements. While 92% had worn a helmet, optimal protection was reported less frequently for other body areas: most often for the feet (54%), hands (47%) and upper body (35%) and least often for the legs (8%). Most (87%) riders considered conspicuity increased safety, 68% favoured mandatory day-time headlight use, and 66% used dipped headlights in day-time. While 55% favoured mandatory wearing of high-visibility clothing, only 15% of day-time and 20% of night-time riders reported doing this. During the past month, 16% had driven within two hours of drinking alcohol and 6% when too tired to be fully in control. Overall, 22% had been penalized for a motorcycle driving offence, most often speeding. While 46% said they agreed with the Graduated Driver Licensing System (GDLS), most licensed under that system reported breaking licence conditions and most were not apprehended. Licensed motorcyclists were significantly more likely than the unlicensed to favour mandatory day-time headlight usage, report using dipped headlights in day-time, and wear better protection for the head, upper body and hands, but were also more likely to report drinking and driving and traffic convictions--probably because of their greater exposure. Other, non-significant, results were in the same direction, except that fewer licensed than unlicensed riders were in favour of mandatory high visibility clothing or the GDLS. A similar pattern of more protective attitudes and behaviours was found for high rather than low exposure riders, though it was generally weaker, and high exposure was associated with drinking and driving, driving while tired and traffic convictions. The issues of representativeness and reliability are discussed and some implications for public policies towards motorcycling by young people are considered. Further research is recommended in order to determine which are the best predictors of motorcycling opinions and behaviours: personal characteristics, the formal training associated with licensure, or exposure to motorcycling.

The New Zealand rugby injury and performance project. III. Anthropometric and physical performance characteristics of players

OBJECTIVE

To investigate the anthropometric and physical performance characteristics of New Zealand rugby players of different ages and both sexes.

METHODS

356 rugby players (264 male, 92 female) took part in the study during a single season. Playing grade ranged from schoolboys and schoolgirls to senior men and women. Assessment of height, weight, neck circumference, and somatotype was performed before the competitive rugby season. A battery of six physical performance assessments was completed after the anthropometry. Analysis of variance was used to examine differences in these variables between field positions and grades.

RESULTS

Significant differences between forwards and backs on anthropometric and physical performance variables were apparent at all grades assessed. In terms of anthropometric characteristics, forwards of a given grade were generally taller, possessed greater body mass, and were more endomorphic and less ectomorphic than backs of the same grade. The backs tended to perform better on physical performance measures than forwards, being more aerobically fit, faster, more agile, and possessing a higher degree of muscular endurance. Differences in anthropometry and physical performance attributes were also apparent between players from the various grades. The players at higher levels were generally larger, and performed better on tests of physical performance than the players at lower levels. These differences were found in both sexes.

CONCLUSIONS

The greater body mass of the forwards allows them to obtain greater momentum than the backs when sprinting. The ability to obtain greater momentum is important in the body contact phases of the game. Forwards may compromise their aerobic fitness and speed to some extent in order to maintain a high body mass. The anthropometric and physical performance characteristics of players appear to reflect the demands placed on them by the sport.

Differential actions of 3-(4-chlorophenyl) glutamic acid stereoisomers and L-trans-pyrrolidine-2,4-dicarboxylic acid upon L-homocysteic acid- and L-glutamic acid-induced responses from rat spinal motoneurones

The four recently synthesized stereoisomers of 3-(4-chlorophenyl) glutamic acid (chlorpheg) were individually examined for their abilities to potentiate depolarizations of neonatal rat motoneurones evoked by L-homocysteic acid (L-HCA, 10 microM). This property had previously been observed using the racemate and is believed to be mediated by uptake inhibition. Both the (2S,3S)- and (2S,3R)- isomers were selective potentiators of L-HCA- (vs L-Glu) induced depolarizations although the (2S,3S)- isomer was more effective. The (2R,3S)- isomer had a slight but significant depressant action which could be attributed to N-methyl-D-aspartate (NMDA) receptor antagonism. Comparison of the potentiating properties of (2S,3S)- and (2S,3R)-chlorpheg with those of L-trans-pyrrolidine-2,4-dicarboxylic acid (tPDC, a L-Glu uptake inhibitor) upon L-HCA- and L-Glu-evoked responses revealed that both chlorpheg isomers (500 microM each) selectively potentiated responses evoked by L-HCA (10 microM) but had no significant effect upon those evoked by L-Glu (50 microM). On the other hand, use of tPDC at the same concentration significantly enhanced the depolarizations evoked by both amino acids, although its action on L-Glu-evoked responses was greater. It is concluded that (i) the (2S,3S)- isomer and to a lesser extent, the (2S,3R)- isomer of chlorpheg are responsible for the potentiating actions seen with the chlorpheg racemate used in previous studies and (ii) (2R,3S)-chlorpheg is a weak NMDA antagonist. The apparently selective action of (2S,3S)- and (2S,3R)-chlorpheg upon L-HCA-relative to L-Glu-induced depolarizations supports the existence of multiple excitatory amino acid uptake sites, some of which may yet be unidentified.

The New Zealand graduated driver licensing system: teenagers' attitudes towards and experiences with this car driver licensing system

OBJECTIVES

This study examined the attitudes of teenagers towards the New Zealand graduated driver licensing system (GDLS), and the extent to which it affected them.

METHOD

Teenagers, who are members of a longitudinal study of a birth cohort, were interviewed at 15 years of age when the GDLS was first introduced and before they had begun licensure, and again at 18 years of age after they had experience with this licensing system.

RESULTS

At both ages the majority (over 70%) agreed with the driving restrictions imposed by this system. After experience with the restrictions, however, significantly more reported being affected a lot by them, than had expected to be at age 15. This was especially true of the restrictions on the carrying of passengers and the night time curfew (10 pm - 5 am). However, few reported that they were affected by the alcohol restriction. Sixty eight per cent of those with a graduated licence reported breaking at least one of the conditions, most frequently carrying passengers. Very few were penalised by the police for this.

CONCLUSIONS

Generally these young drivers were positively disposed towards the driving restrictions, but noncompliance was common. A full evaluation of all aspects of this licensing system is recommended.

Young on-road motorcyclists in New Zealand: age of licensure, unlicensed riding, and motorcycle borrowing

OBJECTIVES

The study aimed to determine the prevalence of unlicensed riding and motorcycle borrowing among young motorcyclists, and to document their perceptions of how they would be affected if the minimum age of licensure were raised.

METHODS

Motorcycling was investigated as part of the Dunedin Multidisciplinary Health and Development Study, a broad longitudinal study of the health, development, attitudes, and behaviours of a birth cohort. Young motorcyclists, who had ridden on-road during the year before their interview at age 18 years, completed a computer administered questionnaire containing questions about licensure, riding frequency, and motorcycle borrowing.

RESULTS

Of the 217 motorcyclists identified, 36% were licensed, 54% had ridden once a month or less frequently, and 72% had usually ridden a borrowed motorcycle during the one year recall period. Significantly more licensed than unlicensed riders and owners than borrowers reported higher exposure and significantly more licensed than unlicensed riders were owners. Most licensed riders (86%) had ridden on public roads before licensure, and many (54%) thought that they would have been much affected by a higher minimum age of licensure.

CONCLUSIONS

More stringent enforcement of existing licensing regulations, tougher penalties for breaching graduated driver licensing restrictions, raising the minimum age for motorcycle licensure, and prohibiting the sale or lending of motorcycles to unlicensed riders are possible injury prevention strategies.

Injury from assault in New Zealand: an increasing public health problem

Injury purposely inflicted by other persons is a significant public health problem accounting for approximately 4 per cent of all injury hospitalisations in New Zealand. National injury morbidity data for the years 1979-1988 were examined. These data were used to identify the characteristics of victims of assault who were hospitalised, the nature of the injuries they sustained, and the circumstances in which the injuries were inflicted. The incidence of hospitalisations in 1988 was 73.7 per 100,000 persons per year. A significant increase in the rate of hospitalisations over the decade 1979-1988 was identified. The rates for males were higher than those for females, with males 20-24 years of age most at risk. Maori had higher rates than non-Maori. Fights or brawls were the leading cause of hospitalisation. The most common place of occurrence was private homes, followed by streets and highways, and licensed premises. The findings with regard to age, sex, employment status and use of weapons were consistent with earlier studies. A higher proportion of incidents occurring in the home was attributed to differences in selection of cases between studies. An indication of underreporting by women was attributed to concealment of intentionality, possible owing to fear of reprisal. Standard hospital reporting procedures were proposed as a means of improving identification.

Homicide in New Zealand: an increasing public health problem

Injury purposely inflicted by other persons is a significant public health problem as well as a criminal problem. It accounts for approximately 3 per cent of all deaths from injury in New Zealand. National injury mortality data for the period 1978 to 1987, supplemented by reference to files of the Coroner's Court and the High Court, were used to identify the characteristics of victims of homicide, the nature of the injuries they sustained, and the circumstances in which the injuries were inflicted. The mortality rate from homicide for the 10-year period was 1.6 per 100,000 persons per year. A significant increase in the rate of homicide was identified. The rates for males were higher (2.0) than those for females (1.2), with those 20 to 24 years of age most at risk. Maori had higher rates than non-Maori. Homicides were most frequently committed with cutting and piercing instruments, and most commonly occurred in private homes. Homicides were most likely to occur on Fridays or Saturdays, between the hours of 6 p.m. and 6 a.m. In 55 per cent of homicides the victim and assailant were known to one another. Unemployment, membership of ethnic minority groups, availability of weapons, the private nature of interactions in the home, alcohol consumption, and stress in personal relationships were all identified as factors associated with homicide in the decade under study. The implications of these findings for the prevention of injury from assault are discussed.

Trampolines in New Zealand: a decade of injuries

Despite international concern about the safety of trampolines, they have become increasingly popular in New Zealand. While internationally attention has centred on a relatively few cases of catastrophic cervical spine injury, little research effort has been directed at placing these incidents in a wider context. To redress this, a descriptive epidemiological study of trampoline-related injury in New Zealand was undertaken. National hospitalization and mortality data for a 10-year period revealed 2098 hospitalizations and two deaths. The incidence rate for hospitalizations increased from 3.1 per 100,000 population per year in 1979 to 9.3 in 1988. Of the hospitalized victims, 71% were injured on home trampolines and 80% fell from the trampoline to the surrounding surface. Fractures were the commonest type of injury (68%), and the body site most frequently involved was the upper limb (53%). There was no evidence of a high incidence of severe head and neck injuries. It was concluded that, although existing trampoline standards addressed many of the issues raised by this research, measures to reduce the impact of falls from trampolines to the ground and to prohibit the provision of trampolines as 'play equipment' are required.

New Zealand's Injury Prevention Research Unit: reducing sport and recreational injury

The Injury Prevention Research Unit was established in 1990 to reduce the incidence, severity and consequences of injury. Research into sport and recreational injury is one of five major areas of research being undertaken. National data sources have been used to estimate the overall size of the problem and to describe the nature and circumstances of injury associated with a variety of sport and recreational activities. Analytical studies are now being undertaken to identify significant risk and protective factors. Research activity is being directed toward the development, implementation and evaluation of preventive measures.

The New Zealand Rugby Injury and Performance Project: I. Design and methodology of a prospective follow-up study

Injury resulting from participation in sporting and physical recreational activities is a major contributor to the overall incidence of injury in the developed world. If sports injuries are to be reduced, a comprehensive approach must be taken to define the nature and magnitude of the problem, to establish models of relationships between risk factors, protective factors and injury experience, and to address injury through well designed intervention and evaluation programmes. The Rugby Injury and Performance Project (RIPP) is a prospective cohort study designed to examine the risk and protective factors for rugby injury. Data were collected on potential risk and protective factors from the RIPP cohort pre-season. Data on exposure to rugby, injury events and medical treatments were collected from the players each week during the season through telephone interviews. Pre-season measures were repeated post-season. A key feature of the design was that data were collected on both injured and non-injured players, allowing a longitudinal comparison of the injury experience of players with and without the factors of interest. A wealth of information was collected on each cohort member during the pre-season interview. A contact rate of 90% was achieved during the weekly follow-up phase. Post-season questionnaires were completed by 76% of the players and 88% of the coaches. Recommendations are made for the use of this methodology by other researchers and future directions for RIPP are described.

Utilization of the resolved L-isomer of 2-amino-6-phosphonohexanoic acid (L-AP6) as a selective agonist for a quisqualate-sensitized site in hippocampal CA1 pyramidal neurons

Brief exposure of rat hippocampal slices to quisqualic acid (QUIS) sensitizes neurons to depolarization by the alpha-amino-omega-phosphonate excitatory amino acid (EAA) analogues AP4, AP5 and AP6. These phosphonates interact with a novel QUIS-sensitized site. Whereas L-AP4 and D-AP5 cross-react with other EAA receptors, DL-AP6 has been shown to be relatively selective for the QUIS-sensitized site. This specificity of DL-AP6, in conjunction with the apparent preference of this site for L-isomers, suggested that the hitherto unavailable L-isomer of AP6 would be a potent and specific agonist. We report the resolution of the D- and L-enantiomers of AP6 by fractional crystallization of the L-lysine salt of DL-AP6. We also report the pharmacological responses of kainate/AMPA, NMDA, lateral perforant path L-AP4 receptors and the CA1 QUIS-sensitized site to D- and L-AP6, and compare these responses to the D- and L-isomers of AP3, AP4, AP5 and AP7. The D-isomers of AP4, AP5 and AP6 were 5-, 3- and 14-fold less potent for the QUIS-sensitized site than their respective L-isomers. While L-AP4 and L-AP5 cross-reacted with NMDA and L-AP4 receptors, L-AP6 was found to be highly potent and specific for the QUIS-sensitized site (IC50 = 40 microM). Its IC50 values for kainate/AMPA, NMDA and L-AP4 receptors were > 10, 3 and 0.8 mM, respectively. As with AP4 and AP5, sensitization to L-AP6 was reversed by L-alpha-aminoadipate.

Falls from moving motor vehicles in New Zealand

Injuries due to falls from moving motor vehicles have received relatively little attention from the research community. Injury events of this type in New Zealand were examined using national injury mortality and hospitalisation data from the New Zealand National Health Statistics Centre (NHSC). Also used were data obtained from the New Zealand Post Motor Registration Centre and from coroner's investigation reports held by the Department of Justice. Fifty-six fatal falls from moving motor vehicles occurred during the period 1977-1986 (0.18 per 100,000 population per year). The average age of fatalities was 23. The total potential years of life lost due to these fatalities was 2,696, or an average of 48 years per person. Thirty-nine persons (70%) fell while riding on the exterior of a vehicle. None of the 56 fatalities was using a belt restraint when he/she fell. Four hundred and twenty-three admissions to hospital occurred during 1986 and 1987 (6.5 per 100,000 persons per year). The average age of those hospitalised was 18. Incidence rates were highest in the 0-4, 15-19, and 20-24 year age groups. In the case of both deaths and hospitalisations, the incidence rate for males was approximately double the rate for females. In addition, the rate of falls (per unit registered motor vehicle) from trucks was significantly higher than the rate of falls from cars. Means of preventing falls from motor vehicles are discussed.

Injuries due to falls from horses

This study describes the epidemiology of injuries due to falls from horses in New Zealand. There were 54 fatalities from 1977 to 1986 (0.17 per 100,000 persons per year). There were 773 hospitalisations in 1987 (23.7 per 100,000 persons per year). Head injuries were predominant among both fatal and nonfatal injuries. The incidence of nonfatal head injury in the 10 to 19 age group was significantly higher than the incidence in all older groups (P = 0.003). Young people, particularly females, were the segment of the population most affected by the problem of falls from horses. Reference to data on horse-riding participation rates, however, did not indicate that young people were overrepresented in the series studied. Reference to the same data showed that the rate of hospitalisation due to falls from horses is comparable to the rate for injuries from playing rugby. The magnitude and severity of the problem indicates that there is a need need for helmet use, safe-riding practices, and further research.