Emma H. Wyeth

Prospective outcomes of injury study

Background: In New Zealand (NZ), 20% of adults report a disability, of which one-third is caused by injury. No prospective epidemiological studies of predictors of disability following all-cause injury among New Zealanders have been undertaken. Internationally, studies have focused on a limited range of predictors or specific injuries. Although these studies provide useful insights, applicability to NZ is limited given the importance of NZ’s unique macro-social factors, such as NZ’s no-fault accident compensation and rehabilitation scheme, the Accident Compensation Corporation (ACC). Objectives: (1) To quantitatively determine the injury, rehabilitation, personal, social and economic factors leading to disability outcomes following injury in NZ. (2) To qualitatively explore experiences and perceptions of injury-related outcomes in face-to-face interviews with 15 Māori and 15 other New Zealanders, 6 and 12 months after injury. Setting: Four geographical regions within NZ. Design: Prospective cohort study with telephone interviews 1, 4 and 12 months after injury. Participants: 2500 people (including 460 Māori), aged 18–64 years, randomly selected from ACC’s entitlement claims register (people likely to be off work for at least 1 week or equivalent). Data: Telephone interviews, electronic hospital and ACC injury data. Exposures include demographic, social, economic, work-related, health status, participation and/or environmental factors. Outcome measures: Primary: disability (including WHODAS II) and health-related quality of life (including EQ-5D). Secondary: participation (paid and unpaid activities), life satisfaction and costs. Analysis: Separate regression models will be developed for each of the outcomes. Repeated measures outcomes will be modelled using general estimating equation models and generalised linear mixed models.

Prospective Outcomes of Injury Study: recruitment, and participant characteristics, health and disability status

The Prospective Outcomes of Injury Study aims to identify predictors of disability following injury. Participants were selected from the entitlement claims register of New Zealands no-fault compensation insurer, the Accident Compensation Corporation, and followed up by interview for 2 years. This report describes changes to intended Prospective Outcomes of Injury Study methods and key characteristics of the cohort, with an emphasis on general health and disability before injury and soon afterwards. There were 2856 injured participants in the first interview, which occurred 3.2 months (median) after injury. The recruitment period was extended to enable inclusion of sufficient Māori participants. At the first interview, most participants were experiencing worse health status and increased disability compared to before injury, despite less than one-third reporting admission to hospital because of their injury. Analysis of outcome predictors related to post-injury function, disability and return-to-work soon after injury and 1 year later is now under way.

Prevalence and predictors of sub-acute phase disability after injury among hospitalised and non-hospitalised groups: a longitudinal cohort study

Introduction To reduce the burden on injury survivors and their supporters, factors associated with poor outcomes need to be identified so that timely post-injury interventions can be implemented. To date, few studies have investigated outcomes for both those who were hospitalised and those who were not. Aim To describe the prevalence and to identify pre-injury and injury-related predictors of disability among hospitalised and non-hospitalised people, three months after injury. Methods Participants in the Prospective Outcomes of Injury Study were aged 18–64 years and on an injury entitlement claims register with New Zealands no-fault injury compensation insurer, following referral by healthcare professionals. A wide range of pre-injury demographic, health and injury-related characteristics were collected at interview. Participants were categorised as ‘hospitalised’ if they were placed on New Zealands National Minimum Data Set within seven days of the injury event. Injury severity scores (NISS) and 12 injury categories were derived from ICD-10 codes. WHODAS assessed disability. Multivariable analyses examined relationships between explanatory variables and disability. Results Of 2856 participants, 2752 (96%) had WHODAS scores available for multivariable analysis; 673 were hospitalised; 2079 were not. Disability was highly prevalent among hospitalised (53.6%) and non-hospitalised (39.4%) participants, three-months after injury. In both groups, pre-injury disability, obesity and higher injury severity were associated with increased odds of post-injury disability. A range of other factors were associated with disability in only one group: e.g. female, ≥2 chronic conditions and leg fracture among hospitalised; aged 35–54 years, trouble accessing healthcare, spine or lower extremity sprains/dislocations and assault among non-hospitalised. Significance Disability was highly prevalent among both groups yet, with a few exceptions, factors associated with disability were not common to both groups. Where possible, including a range of injured people in studies, hospitalised and not, will increase understanding of the burden of disability in the sub-acute phase.

Prevalence and predictors of disability 24-months after injury for hospitalised and non-hospitalised participants: results from a longitudinal cohort study in New Zealand.

Introduction Most studies investigating disability outcomes following injury have examined hospitalised patients. It is not known whether variables associated with disability outcomes are similar for injured people who are not hospitalised. Aims This paper compares the prevalence of disability 24 months after injury for participants in the Prospective Outcomes of Injury Study who were hospitalised and those non-hospitalised, and also seeks to identify pre-injury and injury-related predictors of disability among hospitalised and non-hospitalised participants. Methods Participants, aged 18–64 years, were recruited from an injury claims register managed by New Zealand’s no-fault injury compensation insurer after referral by health care professionals. A wide range of pre-injury socio-demographic, health and psychosocial characteristics were collected, as well as injury-related characteristics; outcome is assessed using the WHODAS. Multivariable models estimating relative risks of disability for hospitalised and non-hospitalised participants were developed using Poisson regression methods. Results Of 2856 participants, analyses were restricted to 2184 (76%) participants for whom both pre-injury and 24 month WHODAS data were available. Of these, 25% were hospitalised. In both hospitalised and non-hospitalised groups, 13% experience disability (WHODAS≥10) 24 months after injury; higher than pre-injury (5%). Of 28 predictor variables, seven independently placed injured participants in the hospitalised group at increased risk of disability 24 months after injury; eight in the non-hospitalised. Only four predictors (pre-injury disability, two or more pre-injury chronic conditions, pre-injury BMI≥30 and trouble accessing healthcare services) were common to both the hospitalised and non-hospitalised groups. There is some evidence to suggest that among the hospitalised group, Māori have higher risk of disability relative to non-Māori. Conclusions At 24 months considerable disability is borne, equally, by hospitalised and non-hospitalised groups. However, predictors of disability are not necessarily consistent between the hospitalised and non-hospitalised groups, suggesting caution in generalising results from one group to the other.

Difficulties in functioning 1 year after injury: the role of preinjury sociodemographic and health characteristics, health care and injury-related factors.

OBJECTIVE To identify the role of preinjury sociodemographic and health characteristics, injury and injury-related health care characteristics in determining functional outcomes 12 months after injury. DESIGN Prospective cohort study involving 1-year follow-up. SETTING Community. PARTICIPANTS Study participants (N=2282; age range, 18-64y inclusive) were those in the Prospective Outcomes of Injury Study who completed the 12-month interview. The original cohort of 2856 were injured and registered with New Zealands national no-fault injury insurance agency. With the exception of injury and hospitalization, information on predictors and outcomes was obtained directly from the participants, primarily by telephone interviews, approximately 3 and 12 months after their injury. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES The functional outcomes of interest were the 5 dimensions of the EQ-5D plus a cognitive dimension. Our multivariate analyses included adjustment for preinjury EQ-5D status and time between injury and the 12-month interview. RESULTS Substantial portions of participants continued to have adverse outcomes, especially pain/discomfort, 12 months after their injury. The significance of factors varied by outcome. Factors adversely associated with at least 3 of the 6 outcomes were preinjury EQ-5D status, being female, aged 45 to 64 years, inadequate household income, preinjury disability, 2 or more prior chronic illnesses, smoking regularly, dislocation or sprains to the spine or upper extremities, and having a relatively severe injury. CONCLUSIONS A range of preinjury sociodemographic and health characteristics are associated with several adverse functional outcomes 1 year after injury, independent of the nature and severity of injury. The latter, however, also have independent effects on the outcomes.

Rangatiratanga and Oritetanga: responses to the Treaty of Waitangi in a New Zealand study.

Introduction. Although opportunities exist for positive experiences in research, Māori in New Zealand, like other indigenous people colonised by Europeans in the nineteenth century, have also been subject to research and associated policies that have had long-lasting negative consequences. Researchers have subsequently been challenged by Māori to conduct research that is acceptable, accountable and relevant. Much of this debate has taken place within the framework of the Treaty of Waitangi, a treaty of cession signed between Māori and British Crown representatives in 1840. Nowadays, health and health research statutes exist that require researchers to respond to the ‘principles’ of the Treaty. Few practical examples of how health researchers have undertaken this have been published. Aims. We examine how, in developing a national study of injury outcomes, we responded to the Treaty. Our study, the Prospective Outcomes of Injury Study, aims to quantitatively identify predictors of disability following injury and to qualitatively explore experiences and perceptions of injury outcomes. Discussion. Responses to the Treaty included: consultation with Māori groups, translation of the questionnaire into te reo Māori, appointment of interviewers fluent in te reo Māori, sufficient numbers of Māori participants to allow Māori-specific analyses and the inclusion of a Māori-specific qualitative component. While this article is located within the New Zealand context, we believe it will resonate with, and be of relevance to, health researchers in other former settler societies. We do not contend this project represents an ‘ideal’ model for undertaking population-based research. Instead, we hope that by describing our efforts at responding to the Treaty, we can prompt wider debate of the complex realities of the research environment, one which is scientifically, ethically and culturally located.

The private label grocery choice: consumer drivers to purchase

Private label products have increased in quality and range in recent years and now make up 17% of grocery sales in New Zealand. These changes mean that private label goods are no longer seen as a ‘budget’ alternative to branded goods, but a legitimate choice for consumers in the supermarket environment. Consumer motivations for private label grocery purchases are examined in this article, with findings suggesting that product category is the most important factor in determining choice between a private label and a branded good, with different levels of purchase risk attributed to different categories of product. The study documents a two-level decision process for consumers of grocery products – pre-purchase and in-store, finding that rational drivers tend to promote pre-purchase preferences and emotional drivers are more active in the store environment.

Factors predictive of subsequent injury in a longitudinal cohort study

Objectives The aims are to: (1) Determine the cumulative incidence of self-reported subsequent injury (of any anatomical site or injury type) occurring between 3 months and 12 months after a sentinel injury among participants in the Prospective Outcomes of Injury Study in New Zealand and (2) Examine the preinjury and injury-related predictors of subsequent injury. Methods Prospective Outcomes of Injury Study participants (n=2282) were interviewed 3 months, 5 months and 12 months after a sentinel injury event. Data were collected about a range of preinjury and injury-related factors at the 3-month interview and about subsequent injury at the 5-month and 12-month interviews. Poisson regression modelling was used to determine the preinjury and injury-related predictors of subsequent injury. Results Between the 3-month and 12 month interviews 28% of the participants reported at least one subsequent injury. Subsequent injury was 34% more likely among participants with a prior injury affecting them at the time of the sentinel injury compared with participants without a prior injury affecting them, and more likely among non-workers (31% more likely) and trade/manual workers (32% more likely) compared with professionals. Participants whose sentinel injury was due to assault were 43% more likely to report a subsequent injury compared with those whose sentinel injury was accidental. A subsequent injury was 23% less likely if the sentinel injury was a lower extremity fracture compared with other injuries, and 21% less likely if the sentinel injury event involved hospitalisation. Conclusions Among general injury populations it may be possible to identify people at increased risk for subsequent injury.

Factors associated with non-participation in one or two follow-up phases in a cohort study of injured adults

Objective To identify factors associated with non-participation at the 12-month and 24-month follow-up phases of a prospective cohort study of injury outcomes. Methods Associations between non-participation at follow-up phases and a range of sociodemographic, injury, health, outcome and administrative factors were examined. Results An individuals non-participation at 12 months did not necessarily mean non-participation at 24 months. Sociodemographic factors were the most salient for non-participation, regardless of the number of follow-up phases or specific phase considered. Conclusions Retention rates in prospective cohort studies of injury outcome may be improved by follow-up of everyone irrespective of previous non-participation, focusing resources to retain men, young adults, indigenous people and those living with people other than family members, and by ensuring that multiple alternative participant contacts are obtained. There is sufficient evidence to be concerned about potential bias given that several of the factors we, and others, have identified as associated with non-participation are also associated with various functional and disability outcomes following injury. This suggests detailed investigations are warranted into the effect non-participation may be having on the estimates for various outcomes.

Indigenous injury outcomes: life satisfaction among injured Māori in New Zealand three months after injury

BackgroundMāori, the indigenous population of New Zealand, experience numerous and consistent health disparities when compared to non-Māori. Injury is no exception, yet there is a paucity of published literature that examines outcomes following a wide variety of injury types and severities for this population. This paper aims to identify pre-injury and injury-related predictors of life satisfaction three months after injury for a group of injured Māori.MethodsThe Māori sample (n = 566) were all participants in the Prospective Outcomes of Injury Study (POIS). POIS is a longitudinal study of 2856 injured New Zealanders aged 18–64 years who were on an injury entitlement claims’ register with New Zealand’s no-fault compensation insurer. The well-known Te Whare Tapa Whā model of overall health and well-being was used to help inform the selection of post-injury life satisfaction predictor variables. Multivariable analyses were used to examine the relationships between potential predictors and life satisfaction.ResultsOf the 566 Māori participants, post-injury life satisfaction data was available for 563 (99%) participants. Of these, 71% reported satisfaction with life three months after injury (compared to 93% pre-injury). Those with a higher injury severity score, not satisfied with pre-injury social relationships or poor self-efficacy pre-injury were less likely to be satisfied with life three months after injury.ConclusionsThe large majority of Māori participants reported being satisfied with life three months after injury; however, nearly a third did not. This suggests that further research investigating outcomes after injury for Māori, and predictors of these, is necessary. Results show that healthcare providers could perhaps put greater effort into working alongside injured Māori who have more severe injuries, report poor self-efficacy and were not satisfied with their pre-injury social relationships to ensure increased likelihood of satisfaction with life soon after injury.