Using hospital discharge data for injury research or surveillance? An observational study illustrating the impact of administrative change.

INTRODUCTION: Hospital discharge data provide an important basis for determining priorities for injury prevention and monitoring trends in incidence. This study aims to illustrate the impact of a recent change in administrative practice on estimates of hospitalised injury incidence and to investigate the extent to which different case selection affects trends in injury incidence rates. METHODS: New Zealand (NZ) hospital discharges (2000-2014) with a primary diagnosis of injury were identified. Additional case selection criteria included first admissions only, and for serious injury, a high threat-to-life estimate. Comparisons were made, over time and by District Health Board, between hospitalised injury incidence estimates that included, or not, short-stay emergency department (SSED) discharges. RESULTS: Of the 1 229 772 injury hospital discharges, 365 114 were SSED; 16% of the annual total in 2000, 38% in 2014. Identification of readmissions prior to the exclusion of SSED discharges resulted in 30 724 cases being erroneously removed. Age-standardised rates of hospitalised injury over the 15-year period increased by, on average, 2.7% per year when SSED discharges were included; there was minimal secular change (-0.2%) when SSEDs were excluded. For serious hospitalised injury, the annual increase was 2.3% when SSED was included compared with 1.1% when SSEDs were excluded. CONCLUSION: Spurious trends in hospitalised injury incidence can result when administrative practices are not appropriately accounted for. Exclusion of SSED discharges before the identification of readmissions and the use of a severity threshold are recommended to minimise the reporting bias in NZ hospitalised injury incidence estimates.

Motorcyclists' perceptions and experiences of riding and risk and their advice for safety.

OBJECTIVE: To examine the knowledge, observations, and perceptions of motorcycle riders on the risks of on-road motorcycling and potential safety measures to give insight and guidance in developing policies, programs, and legislation to improve the safety of motorcyclists. METHODS: Individual and focus group interviews were conducted with dealers and a cross section of motorcyclists from selected regions across New Zealand. The interviews were analyzed and coded to identify common themes and diverse perspectives on why people rode motorcycles, riders' perceptions on risk, and possible safety strategies for on-road motorcycling. FINDINGS AND DISCUSSION: Motorcycling has major benefits for riders, although most riders perceived that the risks could be severe and they were susceptible to injury. Their observations on the threats and barriers to safety focused on 3 components: the rider, the motorcycle, and the environment. Risks included inexperience, not riding to the conditions, choice of motorcycle, protective clothing and conspicuity, and speed. The underlying risk of being on 2 wheels was accentuated by the availability of high-power motorcycles. The threats perceived in the environment included the behavior of other road users, especially car drivers, and the poor road conditions and surrounds encountered. CONCLUSIONS: Riders identified risks that have been recognized in the road safety literature as well as risks for which there are no engineering or scientific solutions. To effectively increase motorcyclist safety, recognition of the commonalities and the differences between motorcyclists' perspectives and proposed strategies is needed. This approach is more likely to engage riders and thus support positive behavior change among riders and drivers.

Preventing unintentional childhood injury at home: injury circumstances and interventions.

New Zealand's (NZ) preschoolers carry the greatest injury burden among children aged 0-14 years. These injuries commonly occur at home. To identify how NZ addresses child injury the 1990s national injury datasets and associated free text were examined retrospectively, NZ injury circumstances and interventions were compared to internationally recognised hazards and best practice, and whether NZ interventions addressed common circumstances of injury was assessed. Certain injuries, often associated with activities of daily living, were not addressed by interventions, although most interventions advocated internationally are implemented in NZ. Possible reasons for main injuries not being addressed were the specificity and variable effectiveness of interventions, normality of many injury circumstances, difficulties in evaluating complex environments, and the need for active intervention. There is considerable scope for NZ to improve its child safety. It is unlikely that simple solutions will be found for complex circumstances in which injury events occur. Strategies to address multifaceted problems requiring changes to personal, social and societal factors are required, with evaluation methods able to match their complexity.

Child home injury prevention: understanding the context of unintentional injuries to preschool children.

Injury to young children at home is a public health problem. In New Zealand, over half the injury deaths and hospitalisations among 0-4 year olds occur at home. Causes and risk factors for child injury have been identified, but their circumstances are not well described. Understanding the context, however, is important for developing and implementing effective prevention. To obtain the descriptions of injury events, semi-structured interviews were conducted with a convenience sample of 100 caregivers of 0-4 year olds attending an emergency department for a home injury. Analysis from this exploratory study indicated that most events occurred within usual family activity, but had multiple factors interacting. Injury was rarely the expected outcome. Findings concurred with findings from others' research that reported home injury to be complex and multifaceted. Factors related to the environment, the child, the parent, their behaviours and activity interacted, with common patterns preceding injury being evident such as times of day and disrupted routines. Factors were often found to occur regardless of the cause of injury. Complex parental factors were identified, such as not anticipating risk, having unrealistic expectations of children, lacking knowledge of child development and accepting injury as a norm. Directions for further research are identified.

Quality of hospital discharge data for injury prevention.

OBJECTIVE: To examine the use of unspecified codes for the circumstances of injury for New Zealand public hospital discharges at a district health board (DHB) level. METHODS: Hospital injury discharges for the period 2000-3 were examined. The use of the International Classification of Diseases unspecified categories was examined for mechanism of injury, activity and place of occurrence. RESULTS: For all DHBs, the combined age-adjusted and mechanism-adjusted usage of unspecified mechanism codes was 7% and ranged from 3% to 11%. Most (57%) of these cases were unspecified falls. The comparable usage for activity was 39% and ranged from 17% to 52%, and for place of occurrence the respective figures were 23% and 7-36%. Only 50% of hospital discharges were completely specified in terms of mechanism of injury, activity and place of occurrence; this varied from 36% to 74% between DHBs. For several DHBs a significant degree of inconsistency was found in performance across mechanism, activity and place of occurrence coding. CONCLUSIONS: Those DHBs with a high proportion of cases coded as unspecified would serve the prevention efforts of their communities better by making efforts to determine the cause of this situation and implement measures to reduce the problem.

The process and impact of implementing injury prevention projects in smaller communities in New Zealand.

It has been argued that developing community projects is an effective means by which to reduce injury. Two pilot community injury prevention projects (CIPPs) were established in small communities in New Zealand based on the World Health Organization (WHO) Safe Community model. The process and impact of the implementation of these CIPPs was monitored over 3 years. The setting was two small New Zealand communities with populations of <10 000. An external process and impact evaluation was conducted, with data gathered from written documentation, informant interviews and observation. The WHO Safe Community criteria formed the basis of the evaluation framework used. Other essential factors included were identified through the literature and the projects themselves. Findings from each CIPP were considered independently, followed by an examination of the differences observed. The findings from the evaluation of the implementation of these CIPPs are reported in relation to the themes identified in the evaluation framework, namely: community context, ownership and participation, focus and planning, data collection, leadership, management, sustainability and external links. Despite the different contexts, a common conclusion was that if the CIPPs' success was dependent on achieving a meaningful reduction of injury, they were unlikely to succeed. There were, however, a number of strategies and outputs for achieving change that could contribute to increasing safety for the population of interest. These were closely linked to community development strategies and needed greater acknowledgement in the evolution of the CIPPs. Critical to the development of the CIPPs were community capacity and the context in which the projects were operating. These conclusions are likely to apply to other projects in such settings, irrespective of the health outcomes sought.