Understanding the Roles of Remoteness and Indigenous Status in Rural and Remote Road Trauma in North Queensland: Using a Mixed-Methods Approach.

Road trauma is a significant health problem in rural and remote regions of Australia, particularly for Indigenous communities. This study aims to identify and compare the circumstances leading to (proximal causation) and social determinants of (distal causation) crashes of Indigenous and non-Indigenous people in these regions and their relation to remoteness. This is a topic seriously under-researched in Australia. Modelled on an earlier study, 229 persons injured in crashes were recruited from local health facilities in rural and remote North Queensland and interviewed, mainly by telephone, according to a fixed protocol which included a detailed narrative of the circumstances of the crash. A qualitative analysis of these narratives identified several core themes, further explored statistically in this sample, supplemented by participants in the earlier study with compatible questionnaire data, designed to determine which factors were more closely associated with Indigenous status and which with remoteness. Indigenous participants were less often vehicle controllers, more likely to have recently been a drink driver or passenger thereof; to be unemployed, unlicensed, distracted or fatigued before the crash, alcohol dependent and have lower perceived social, but not personal, locus of control in a traffic crash than non-Indigenous persons. Differences between Indigenous and non-Indigenous participants are largely ascribable to hardship and transport disadvantage due to lack of access to licensing and associated limitations on employment opportunities. Based on these findings, a number of policy recommendations relating to educational, enforcement and engineering issues have been made.

The impact of changes to the NSW graduated driver licensing system on subsequent crash and offense experience.

INTRODUCTION: In mid-2007 the State of New South Wales (NSW) in Australia introduced modifications to the existing graduated driver licensing system, lengthening the mandatory number of supervised hours for learner drivers aged under 25 years from 50 to 120 and extending the minimum learner period from 6 to 12 months. Additional driving restrictions were also introduced for young drivers in the two provisional licensed periods, P1, P2. This paper aims to evaluate this change by comparing the crash and offense experiences of young learner drivers before and after it occurred. METHOD: From driver licensing files supplied by the NSW transport authority two cohorts of persons obtaining their initial learner's permits in the year prior to the changes and in the subsequent year were constructed with demographic data, dates of transition to the driving phases, dates of crashes, and dates and types of traffic offenses. Both cohorts comprised around 100,000 individuals. Crash rates per 100 years of person-time under observation post P1 with their standard errors were calculated. Using a survival-analytic approach the proportion of crashes of all types were graphed in three month periods post P1. Sexes were treated separately as were initial learner ages of 16, 17, 18-21, and 22-24 years. The distribution of traffic offense types during P1 and P2 phases were also compared. With such large numbers formal statistical testing was avoided. RESULTS: No meaningful differences in the crash or offense experiences of the two cohorts in either sex or at any age were observed. Delaying progress to unsupervised driving has road safety benefits. CONCLUSIONS: At least in conditions similar to those in NSW, requiring more than 50 h of supervised driving seems to have few road safety benefits. Practical applications: Licensing authorities should be cautious in extending the mandated number of supervised driving hours beyond 50.

Treatment of clozapine-associated obesity and diabetes with exenatide in adults with schizophrenia: A randomized controlled trial (CODEX).

Clozapine causes obesity and type 2 diabetes (T2DM). Glucagon-like peptide-1 (GLP-1) receptor agonists (e.g. exenatide) can counter clozapine-associated GLP-1 dysregulation in animals, and may be beneficial in people on clozapine. This randomized, controlled, open-label, pilot trial evaluated weekly exenatide for weight loss among clozapine-treated obese adults with schizophrenia, with or without T2DM. A total of 28 outpatients were randomized to once-weekly extended-release subcutaneous exenatide or usual care for 24 weeks. The primary outcome was proportion of participants with >5% weight loss. All 28 participants completed the study; 3/14 in the exenatide group and 2/14 in the usual care group had T2DM. Six people on exenatide achieved >5% weight loss vs one receiving usual care (P = .029). Compared with usual care, participants on exenatide had greater mean weight loss (-5.29 vs -1.12 kg; P = .015) and body mass index reduction (-1.78 vs -0.39 kg/m2 ; P = .019), and reduced fasting glucose (-0.34 vs 0.39 mmol/L; P = .036) and glycated haemoglobin levels (-0.21% vs 0.03%; P = .004). There were no significant differences in other metabolic syndrome components. Exenatide may be a promising therapeutic agent for glycaemic control and weight loss in clozapine-treated people with obesity, and could assist in reducing clozapine-associated cardio-metabolic morbidity and mortality.

Clozapine Response Rates among People with Treatment-Resistant Schizophrenia: Data from a Systematic Review and Meta-Analysis.

Clozapine is the most effective antipsychotic for the 25% to 33% of people with schizophrenia who are treatment resistant, but not all people achieve response. Using data from a previously published clozapine systematic review and meta-analysis, we explored the proportion of people who achieved response and examined the absolute and percentage change in Positive and Negative Syndrome Scale (PANSS) scores. Overall, 40.1% (95% confidence interval [CI], 36.8%-43.4%) responded, with a mean reduction in PANSS of 22.0 points (95% CI, 20.9-23.1), a reduction of 25.8% (95% CI, 24.7%-26.9%) from baseline. These reductions are clinically meaningful. A 40% response rate to clozapine suggests that 12% to 20% of people with schizophrenia will be ultra-resistant.

Patterns of Injury in Hospitalised One-Year-Old Children: Analysis by Trimester of Age Using Coded Data and Textual Description.

The second year of life is a time of rapid developmental changes. This paper aims to describe the pattern of unintentional injuries to one-year old children in three-month age bands to better understand the risks associated with developmental stages and, therefore, identify opportunities for proactive prevention. Injury surveillance data were used to identify children admitted to hospital in Queensland, Australia for an unintentional injury from 2002-2012. Falls were the most common injury, followed by burns and scalds, contact injuries and poisonings. Falls and contact injuries remained roughly constant by age, burns and scalds decreased and poisonings (by medications) increased. Animal- and transport-related injuries also became more common, immersions and other threats to breathing less common. Within the falls and contact categories falls from play equipment and injuries due to contact with persons increased, while falls down stairs and catching fingers in doors decreased. The pattern of injuries varies over the second year of life and is clearly linked to the child's increasing mobility and boldness. Preventive measures for young children need to be designed-and evaluated-with their developmental stage in mind, using a variety of strategies, including opportunistic, developmentally specific education of parents; and practitioners should also consider potential for lapses in supervision and possible intentional injury in all injury assessments.

Trial of the Primary Care Practice Improvement Tool: building organisational performance in Australian general practice and primary health care.

OBJECTIVE: To nationally trial the Primary Care Practice Improvement Tool (PC-PIT), an organisational performance improvement tool previously co-created with Australian primary care practices to increase their focus on relevant quality improvement (QI) activities. DESIGN: The study was conducted from March to December 2015 with volunteer general practices from a range of Australian primary care settings. We used a mixed-methods approach in two parts. Part 1 involved staff in Australian primary care practices assessing how they perceived their practice met (or did not meet) each of the 13 PC-PIT elements of high-performing practices, using a 1-5 Likert scale. In Part 2, two external raters conducted an independent practice visit to independently and objectively assess the subjective practice assessment from Part 1 against objective indicators for the 13 elements, using the same 1-5 Likert scale. Concordance between the raters was determined by comparing their ratings. In-depth interviews conducted during the independent practice visits explored practice managers' experiences and perceived support and resource needs to undertake organisational improvement in practice. RESULTS: Data were available for 34 general practices participating in Part 1. For Part 2, independent practice visits and the inter-rater comparison were conducted for a purposeful sample of 19 of the 34 practices. Overall concordance between the two raters for each of the assessed elements was excellent. Three practice types across a continuum of higher- to lower-scoring practices were identified, with each using the PC-PIT in a unique way. During the in-depth interviews, practice managers identified benefits of having additional QI tools that relate to the PC-PIT elements. CONCLUSIONS: The PC-PIT is an organisational performance tool that is acceptable, valid and relevant to our range of partners and the end users (general practices). Work is continuing with our partners and end users to embed the PC-PIT in existing organisational improvement programs.

Development and validation of a melanoma risk score based on pooled data from 16 case-control studies.

BACKGROUND: We report the development of a cutaneous melanoma risk algorithm based upon seven factors; hair color, skin type, family history, freckling, nevus count, number of large nevi, and history of sunburn, intended to form the basis of a self-assessment Web tool for the general public. METHODS: Predicted odds of melanoma were estimated by analyzing a pooled dataset from 16 case-control studies using logistic random coefficients models. Risk categories were defined based on the distribution of the predicted odds in the controls from these studies. Imputation was used to estimate missing data in the pooled datasets. The 30th, 60th, and 90th centiles were used to distribute individuals into four risk groups for their age, sex, and geographic location. Cross-validation was used to test the robustness of the thresholds for each group by leaving out each study one by one. Performance of the model was assessed in an independent UK case-control study dataset. RESULTS: Cross-validation confirmed the robustness of the threshold estimates. Cases and controls were well discriminated in the independent dataset [area under the curve, 0.75; 95% confidence interval (CI), 0.73-0.78]. Twenty-nine percent of cases were in the highest risk group compared with 7% of controls, and 43% of controls were in the lowest risk group compared with 13% of cases. CONCLUSION: We have identified a composite score representing an estimate of relative risk and successfully validated this score in an independent dataset. IMPACT: This score may be a useful tool to inform members of the public about their melanoma risk.

Development and pilot study of the Primary Care Practice Improvement Tool (PC-PIT): an innovative approach.

OBJECTIVE: To assess the usability and validity of the Primary Care Practice Improvement Tool (PC-PIT), a practice performance improvement tool based on 13 key elements identified by a systematic review. It was co-created with a range of partners and designed specifically for primary health care. DESIGN: This pilot study examined the PC-PIT using a formative assessment framework and mixed-methods research design. SETTING AND PARTICIPANTS: Six high-functioning general practices in Queensland, Australia, between February and July 2013. A total of 28 staff participated - 10 general practitioners, six practice or community nurses, 12 administrators (four practice managers; one business manager and eight reception or general administrative staff). MAIN OUTCOME MEASURES: Readability, content validity and staff perceptions of the PC-PIT. RESULTS: The PC-PIT offers an appropriate and acceptable approach to internal quality improvement in general practice. Quantitative assessment scores and qualitative data from all staff identified two areas in which the PC-PIT required modification: a reduction in the indicative reading age, and simplification of governance-related terms and concepts. CONCLUSION: The PC-PIT provides an innovative approach to address the complexity of organisational improvement in general practice and primary health care. This initial validation will be used to develop a suite of supporting, high-quality and free-to-access resources to enhance the use of the PC-PIT in general practice. Based on these findings, a national trial is now underway.

Nomograms to predict recurrence and survival in stage IIIB and IIIC melanoma after therapeutic lymphadenectomy.

BACKGROUND: Current staging algorithms in melanoma patients undergoing therapeutic lymph node dissection (LND) fail to accurately distinguish long-term survivors from those at risk of rapid relapse. Our goal was to establish and validate nomograms for predicting both recurrence and survival after LND. METHODS: A prospective cohort of stage IIIB and IIIC melanoma patients was ascertained from a tertiary hospital in Brisbane, Australia. Failure-time multivariate analysis identified key factors that, in adjusted combinations, generated nomograms to predict 2-year recurrence and 5-year melanoma-specific survival. The predictive value of these nomograms was further validated in a patient cohort from Rotterdam, The Netherlands. RESULTS: In 494 Australian patients, number of positive lymph nodes, extra-capsular extension and nodular histopathological subtype were the main independent predictors of 2-year recurrence while age, number of positive nodes and extra-capsular extension were the independent predictors of survival. Predictive value was confirmed in The Netherlands cohort of 331 patients. The nomograms were able to classify patients according to their 2-year recurrence and 5-year survival rates even within each stage III sub-class. CONCLUSIONS: Models that include extra-capsular extension predict outcomes in patients with clinically involved lymph nodes. This tool may help tailor treatment and monitoring of this group of patients.

A retrospective quasi-experimental study of a transitional housing program for patients with severe and persistent mental illness.

Transitional housing programs aim to improve living skills and housing stability for tenuously housed patients with mental illness. 113 consecutive Transitional Housing Team (THT) patients were matched to 139 controls on diagnosis, time of presentation, gender and prior psychiatric hospitalisation and compared using a difference-in-difference analysis for illness acuity and service use outcomes measured 1 year before and after THT entry/exit. There was a statistically significant difference-in-difference favouring THT participants for bed days (mean difference in difference -20.76 days, SE 9.59, p = 0.031) and living conditions (HoNOS Q11 mean difference in difference -0.93, SE 0.23, p < 0.001). THT cost less per participant (I$14,024) than the bed-days averted (I$17,348). The findings of reductions in bed days and improved living conditions suggest that transitional housing programs can have a significant positive impact for tenuously housed patients with high inpatient service usage, as well as saving costs for mental health services.

Virus-associated apoptosis of blood neutrophils as a risk factor for invasive meningococcal disease.

AIMS: To quantify a range of haematological indicators of viral infection (leucocyte apoptosis, cytopenia of normal lymphocytes, reactive lymphocyte increase, neutropenia) in patients with recent onset invasive meningococcal disease (IMD), with a view to test the association of viral infection with IMD and identify possible haematological risk factors for its development. SUBJECTS AND METHODS: 88 patients with recent onset IMD, classified on clinical severity as fatal (n=14), septic shock survived (n=26) and no shock (n=48), and 50 healthy controls were studied. Blood film microscopy and leucocyte counts were used to quantify the virus-associated indicators. Cocci-containing neutrophils were also quantified. RESULTS: All viral parameters were significantly more frequent or higher in patients than controls, with leucocyte apoptosis found only in the patients. A significant gradient in accord with clinical severity was found for neutrophil and lymphocyte apoptosis, neutropenia and cocci-containing neutrophils. Crucially, apoptotic neutrophils did not contain cocci, and cocci-containing neutrophils were not apoptotic. CONCLUSIONS: The correlation between magnitude of neutrophil apoptosis and severity of IMD suggests a cause-effect relationship. We propose that neutrophil apoptosis is more likely a facilitator rather than an effect of IMD for these reasons: (1) apoptotic neutrophils did not contain cocci and cocci-containing neutrophils were not apoptotic, (2) leucocyte apoptosis is a recognised viral effect and (3) Neisseria meningitidis is incapable of producing a Panton-Valentine type leucocidin. The lymphocyte apoptosis which accompanies neutrophil death may contribute to risk by impairing the generation of microbicidal antibody. Leucocyte apoptosis is a morphological expression of viral immunosuppression and, we suggest, is a likely contributor to a range of viral effects.

Injuries leading to hospitalisation in the first year of life: analysis by trimester of age using coded data and textual description.

OBJECTIVE: To describe unintentional injuries to children aged less than one year, using coded and textual information, in three-month age bands to reflect their development over the year. METHODS: Data from the Queensland Injury Surveillance Unit was used. The Unit collects demographic, clinical and circumstantial details about injured persons presenting to selected emergency departments across the State. Only injuries coded as unintentional in children admitted to hospital were included for this analysis. RESULTS: After editing, 1,082 children remained for analysis, 24 with transport-related injuries. Falls were the most common injury, but becoming proportionately less over the year, whereas burns and scalds and foreign body injuries increased. The proportion of injuries due to contact with persons or objects varied little, but poisonings were relatively more common in the first and fourth three-month periods. Descriptions indicated that family members were somehow causally involved in 16% of injuries. Our findings are in qualitative agreement with comparable previous studies. CONCLUSION: The pattern of injuries varies over the first year of life and is clearly linked to the child's increasing mobility. IMPLICATIONS: Injury patterns in the first year of life should be reported over shorter intervals. Preventive measures for young children need to be designed with their rapidly changing developmental stage in mind, using a variety of strategies, one of which could be opportunistic developmentally specific education of parents.

Risk factors for lentigo maligna melanoma compared with superficial spreading melanoma: a case-control study in Australia.

OBJECTIVE: To investigate risk factors for lentigo maligna melanoma (LMM) compared with superficial spreading melanoma (SSM). DESIGN: Population-based case-control study in Queensland, Australia. SETTING: General community. PARTICIPANTS: Population-based sample of 49 patients with LMM and 141 with SSM (in situ or invasive) aged 14 to 86 years at diagnosis in 1979 and 1980 and 232 control subjects. Response rates were 97.1% in cases and 91.8% in controls. MAIN OUTCOME MEASURES: Risks of both subtypes in relation to phenotypic and environmental factors, estimated by multinomial logistic regression. RESULTS: The number of solar lentigines was the strongest determinant for LMM (odds ratio [OR], 15.93; P < .001 for trend) and significantly weaker for SSM (4.61; P < .001 for trend; P = .04 for homogeneity). Skin cancer history was significantly associated with LMM (OR, 2.84) but not with SSM (1.33; P = .07 for homogeneity). In contrast, the number of nevi was the strongest determinant for SSM (OR, 23.22; P < .001 for trend) while significantly weaker for LMM (3.60; P = .02 for trend; P < .001 for homogeneity). Multiple lifetime sunburns almost tripled the risk for SSM, whereas no association was detected with LMM (P = .04 for homogeneity). Shared risk factors for both subtypes were the number of solar keratoses (P < .001 for trend for both) and sun-sensitive complexion (ie, light eye/hair colors, sunburn propensity, and freckling) (2-fold to 5-fold increased risks). CONCLUSIONS: A propensity to lentigines is a stronger predictor of LMM, whereas high nevus propensity is a stronger predictor of SSM. Skin cancer history appears to determine LMM risk only, whereas the number of lifetime sunburns determines SSM only. Prevention strategies could be tailored differently given these distinctive points of difference.

Risk factors for limb melanomas compared with trunk melanomas in Queensland.

The objective of this study was to investigate the risk factors for melanoma on the arms and legs in comparison with well-known risk factors for trunk melanoma. The study was a population-based case-control study of 77 individuals with limb (25 arm; 52 leg) and 86 with trunk melanoma, who were representative of all the individuals newly-diagnosed with primary limb melanomas in Queensland during 1979-1980 and 232 controls. A single physician interviewed and examined all individuals and assessed complexion type, sun exposure history and other potential risk factors and clinical features. After multivariate analysis, the strongest risk factor for both limb and trunk melanomas was the presence of more than 10 naevi on the arm (odds ratio limb melanoma=41.4, 95% confidence interval 10.4-164), though on histology, a preexisting naevus was more strongly associated with trunk than limb melanoma (P<0.004). Associations with blonde/light brown hair, propensity to freckle and sunburn were similar for melanoma on both sites. A lifetime history of painful sunburns significantly raised the risk of trunk but not limb melanoma, whereas solar keratoses on the arm or face were more strongly associated with limb than with trunk melanoma (marginally significant, P(homogeneity)=0.056). High ambient solar ultraviolet radiation in adolescence was also a stronger risk factor for limb than for trunk melanoma. In conclusion, this population-based investigation into specific differences in causes of limb versus melanomas of other sites suggests that the risk factor profile is intermediate between the profiles for head/neck melanoma (mostly cumulative sun damage) and for trunk melanomas (most strongly related to naevi).

Dermoscopic naevus patterns in people at high versus moderate/low melanoma risk in Queensland.

INTRODUCTION: Dermoscopic understanding of naevus characteristics is essential baseline knowledge for identifying early malignant changes. METHOD: This cross-sectional study includes 34 patients (56% female, mean age 48 years) at high risk of melanoma (personal or a first degree family member with history of melanoma) and 31 moderate/low melanoma risk volunteers (55% female, mean age 37 years) recruited at the Princess Alexandra Hospital, Brisbane, between October 2009 and March 2010. Participants received full body and individual dermoscopic imaging of clinically significant naevi (≥2 mm on the back of male/female and lower limbs of female and ≥5 mm at other body sites). Dermoscopic patterns of naevi were compared between people at high versus moderate/low melanoma risk according to age and body site. RESULTS: In both high and moderate/low risk groups, globular naevi predominated on the head/neck and abdomen/chest, reticular and non-specific naevi on the back, and non-specific pattern on the upper and lower limbs. Non-specific naevi were the most common in all age groups. In both risk groups, globular naevi were more frequent in the younger age bracket, and reticular naevi were more frequent in the older age bracket. Mixed naevus patterns were infrequent and were more common in the younger age brackets of both risk groups. CONCLUSION: Our preliminary data shows that dermoscopic naevus patterns were similar for age and body site in people at different levels of melanoma risk, suggesting high melanoma risk does not influence dermoscopic naevus patterns.

Risk factors for fatal crashes in rural Australia.

This paper presents findings from the rural and remote road safety study, conducted in Queensland, Australia, from March 2004 till June 2007, and compares fatal crashes and non-fatal but serious crashes in respect of their environmental, vehicle and operator factors. During the study period there were 613 non-fatal crashes resulting in 684 hospitalised casualties and 119 fatal crashes resulting in 130 fatalities. Additional information from police sources was available on 103 fatal and 309 non-fatal serious crashes. Over three quarters of both fatal and hospitalised casualties were male and the median age in both groups was 34 years. Fatal crashes were more likely to involve speed, alcohol and violations of road rules and fatal crash victims were 2½ times more likely to be unrestrained inside the vehicle than non-fatal casualties, consistent with current international evidence. After controlling for human factors, vehicle and road conditions made a minimal contribution to the seriousness of the crash outcome. Targeted interventions to prevent fatalities on rural and remote roads should focus on reducing speed and drink driving and promoting seatbelt wearing.

Nevi, family history, and fair skin increase the risk of second primary melanoma.

Although risk factors for primary cutaneous melanoma are well defined, relatively little is known about predictors for second primary melanoma. Given the rising incidence of this cancer, coupled with improvements in survival, there is a prevalent and growing pool of patients at risk of second primary melanomas. To identify the predictors of second primary melanoma, we followed a cohort of 1,083 Queensland patients diagnosed with incident melanoma between 1982 and 1990 and who completed a baseline questionnaire. During a median follow-up of 16.5 years, 221 patients were diagnosed with at least one additional primary melanoma. In multivariate analyses, second primary melanomas were associated with high nevus count (hazard ratio (HR), 2.91; 95% confidence interval (CI) 1.94-4.35), high familial melanoma risk (HR, 2.12; 95% CI 1.34-3.36), fair skin (HR, 1.51; 95% CI 1.06-2.16), inability to tan (HR, 1.66; 95% CI 1.13-2.43), an in situ first primary melanoma (HR, 1.36; 95% CI 0.99-1.87), and male sex (HR, 1.49; 95% CI 1.12-2.00). Patients whose first primary was lentigo maligna melanoma (HR, 1.80; 95% CI 1.05-3.07) or nodular melanoma (HR, 2.13; 95% CI 1.21-3.74) had higher risks of subsequent primaries than patients whose first primary tumor was superficial spreading melanoma. These characteristics could be assessed in patients presenting with first primary melanoma to evaluate risk of developing a second primary.

Breastfeeding and risk of epithelial ovarian cancer.

OBJECTIVE: Several studies have found inverse associations between breastfeeding and ovarian cancer occurrence but there are inconsistencies. The relationship with breastfeeding duration is unclear, and it is uncertain whether the association varies according to histological subtype of ovarian cancer. We sought to clarify these issues. METHODS: Parous women who participated in an Australia-wide population-based case-control study of epithelial ovarian cancer between 2001 and 2005 (1,092 cases and 1,288 controls) completed a reproductive/lifestyle questionnaire. Logistic regression was used to calculate odds ratios and 95% confidence intervals to investigate relations between breastfeeding and ovarian cancer. RESULTS: We found a strong inverse association between total duration of breastfeeding (all episodes combined) and ovarian cancer occurrence (OR = 0.986, 95% CI 0.978-0.994 per month of breastfeeding) that appeared to be independent of parity. However, individual episodes of lactation beyond 12 months conferred no appreciable additional benefit. The relation with breastfeeding appeared to vary by histological subtype such that we saw no association between duration of breastfeeding and borderline serous cancers or mucinous cancers, but inverse associations for the other subtypes, although these were not always statistically significant. CONCLUSIONS: A long total duration of breastfeeding appears to be associated with a substantial reduction in the overall risk of ovarian cancer, independent of the decrease in risk due to childbirth, but this may vary according to histological subtype.

Sun exposure and melanoma risk at different latitudes: a pooled analysis of 5700 cases and 7216 controls.

BACKGROUND: Melanoma risk is related to sun exposure; we have investigated risk variation by tumour site and latitude. METHODS: We performed a pooled analysis of 15 case-control studies (5700 melanoma cases and 7216 controls), correlating patterns of sun exposure, sunburn and solar keratoses (three studies) with melanoma risk. Pooled odds ratios (pORs) and 95% Bayesian confidence intervals (CIs) were estimated using Bayesian unconditional polytomous logistic random-coefficients models. RESULTS: Recreational sun exposure was a risk factor for melanoma on the trunk (pOR = 1.7; 95% CI: 1.4-2.2) and limbs (pOR = 1.4; 95% CI: 1.1-1.7), but not head and neck (pOR = 1.1; 95% CI: 0.8-1.4), across latitudes. Occupational sun exposure was associated with risk of melanoma on the head and neck at low latitudes (pOR = 1.7; 95% CI: 1.0-3.0). Total sun exposure was associated with increased risk of melanoma on the limbs at low latitudes (pOR = 1.5; 95% CI: 1.0-2.2), but not at other body sites or other latitudes. The pORs for sunburn in childhood were 1.5 (95% CI: 1.3-1.7), 1.5 (95% CI: 1.3-1.7) and 1.4 (95% CI: 1.1-1.7) for melanoma on the trunk, limbs, and head and neck, respectively, showing little variation across latitudes. The presence of head and neck solar keratoses was associated with increased risk of melanoma on the head and neck (pOR = 4.0; 95% CI: 1.7-9.1) and limbs (pOR = 4.0; 95% CI: 1.9-8.4). CONCLUSION: Melanoma risk at different body sites is associated with different amounts and patterns of sun exposure. Recreational sun exposure and sunburn are strong predictors of melanoma at all latitudes, whereas measures of occupational and total sun exposure appear to predict melanoma predominately at low latitudes.

A pooled analysis of melanocytic nevus phenotype and the risk of cutaneous melanoma at different latitudes.

An abnormal nevus phenotype is associated with an increased risk of melanoma. We report a pooled analysis conducted using individual nevus data from 15 case-control studies (5,421 melanoma cases and 6,966 controls). The aims were to quantify the risk better and to determine whether relative risk is varied by latitude. Bayesian unconditional logistic random coefficients models were employed to study the risk associated with nevus characteristics. Participants with whole body nevus counts in the highest of 4 population-based categories had a greatly increased risk of melanoma compared with those in the lowest category (pooled odds ratio (pOR) 6.9 (95% confidence interval (CI): 4.4, 11.2) for those aged<50 years and pOR 5.1 (95% CI: 3.6, 7.5) for those aged>or=50). The pOR for presence compared with absence of any clinically atypical nevi was 4.0 (95% CI: 2.8, 5.8). The pORs for 1-2 and >or=3 large nevi on the body compared with none were 2.9 (95% CI: 1.9, 4.3) and 7.1 (95% CI: 4.7, 11.6), respectively. The relative heterogeneities among studies were small for most measures of nevus phenotype, except for the analysis of nevus counts on the arms, which may have been due to methodological differences among studies. The pooled analysis also suggested that an abnormal nevus phenotype is associated most with melanomas on intermittently sun-exposed sites. The presence of increased numbers of nevi, large nevi and clinically atypical nevi on the body are robust risk factors for melanoma showing little variation in relative risk among studies performed at different latitudes.