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Taane Clark

Publications and source records attributed to Taane Clark.

6 recordsLinked to original sources

The genetic basis for smoking behavior: a systematic review and meta-analysis.

Considerable evidence indicates that smoking behavior is under a degree of genetic influence. We conducted a systematic review of candidate gene studies of smoking behavior and, where sufficient studies existed, combined reported data using meta-analytic techniques. A total of 41 studies were identified by the search strategy, of which 28 contributed to the meta-analysis. The meta-analysis included data on the DRD2, DAT, 5HTT, and CYP2A6 genes and smoking behavior. Categorical data were extracted on smoking status (never-smoker, ex-smoker, current smoker). Continuous data were extracted on number of cigarettes smoked per day. Evidence indicated effects of the DRD2 Taq1A polymorphism and smoking initiation, the 5HTT LPR and CYP2A6 reduced-activity polymorphisms and smoking cessation, and the DRD2 Taq1A and CYP2A6 reduced-activity polymorphisms and cigarette consumption. The evidence for an effect of specific genes was modest, however, and evidence indicated substantial between-study heterogeneity in most cases, with the exception of the effects of the 5HTT and CYP2A6 genes on smoking cessation. When a random-effects model was applied to analyses in which evidence indicated significant heterogeneity, the effects were in all cases no longer statistically significant. The evidence for a contribution of specific genes to smoking behavior remains modest. Implications for the design of future studies are discussed, such as the need for the development of more specific phenotypes to increase the genetic signal in candidate gene studies.

Genetic Predisposition to Disease↗

Missing... presumed at random: cost-analysis of incomplete data.

When collecting patient-level resource use data for statistical analysis, for some patients and in some categories of resource use, the required count will not be observed. Although this problem must arise in most reported economic evaluations containing patient-level data, it is rare for authors to detail how the problem was overcome. Statistical packages may default to handling missing data through a so-called 'complete case analysis', while some recent cost-analyses have appeared to favour an 'available case' approach. Both of these methods are problematic: complete case analysis is inefficient and is likely to be biased; available case analysis, by employing different numbers of observations for each resource use item, generates severe problems for standard statistical inference. Instead we explore imputation methods for generating 'replacement' values for missing data that will permit complete case analysis using the whole data set and we illustrate these methods using two data sets that had incomplete resource use information.

Algorithms↗

Expression profile of wild-type ETV6 in childhood acute leukaemia.

Comparative expression analysis of wild-typeETV6 in the disease state showed an absence of expression in ETV6-CBFA2 acute lymphoblastic leukaemia (ALL) when compared with non-ETV6-CBFA2 ALL and acute myeloid leukaemia. Fluorescent in-situ hybridization and loss of heterozygosity studies showed that 73% of the ETV6-CBFA2 samples had a fully or partially deleted second ETV6 allele, explaining the lack of wild-type expression in these patients. Although the second ETV6 allele was identified in the remaining patients, no ETV6 expression was detected. These observations support the hypothesis that loss of ETV6 expression is a critical secondary event for leukaemogenesis in ETV6-CBFA2 ALL.

Acute Disease↗

Is body mass index a risk factor for motor vehicle driver injury? A cohort study with prospective and retrospective outcomes.

OBJECTIVE: To investigate the association between risk of motor vehicle driver injury and body mass index (BMI). METHODS: In a cohort study of 10 525 New Zealand men and women, BMI was assessed in 1992-1993 (baseline), and data on deaths and hospitalizations for motor vehicle driver injury were obtained by record linkage to national health databases for the period 1988-1998. Hazard ratios (HR) and CI were estimated by Cox regression. RESULTS: During a mean 10.3 years of follow-up, 139 fatal and non-fatal driver injury cases occurred (85 before baseline and 54 after). A U-shaped association was observed between driver injury risk and BMI, both crudely and after adjustment for covariates, which included age, sex, driving exposure, and alcohol intake (P-values for quadratic trend </=0.02). Participants in the highest (>/=28.7 kg/m(2); HR = 2.00, 95% CI: 1.18-3.39) and lowest (<23.5 kg/m(2); HR = 2.17, 95% CI: 1.27-3.73) quartiles of BMI were twice as likely to have experienced a driver injury during the follow-up period as participants in the reference quartile (25.9-28.6 kg/m(2); HR = 1.00). CONCLUSION: Further research is needed to corroborate or refute the hypothesis that BMI is a risk factor for serious motor vehicle driver injury.

Accidents, Traffic↗

Recurrence after abdominal surgery for Crohn's disease: relationship to disease site and surgical procedure.

PURPOSE: We investigated the hypothesis that there is an "aggressive" subtype of Crohn's disease characterized by early recurrence and that disease location and surgical procedure are associated with differing patterns of recurrence. METHODS: We analyzed 280 patient records totaling 482 major abdominal operations from a prospectively compiled Crohn's disease database. Patterns of recurrence, as defined by reoperation, were analyzed by Kaplan-Meier plots and log-rank tests for the group as a whole, as well as according to disease location and operation performed using log-rank and Cox regression analysis. RESULTS: The overall survival curve followed a simple curve with no apparent early rise in recurrence. There was a significantly higher recurrence rate for ileal disease than for ileocolic or colic disease (median reoperation-free survival, 37.8 vs. 47.8 and 54.7 months, respectively; log-rank test = 13.6; P = 0.001), and there was a significantly shorter reoperation-free survival for those patients treated by strictureplasty alone or stricture-plasty combined with resection than for those treated by resection alone (41.7 and 48.6 vs. 51 months, respectively; log-rank test = 12; P = 0.002), but only disease site was confirmed as an independent risk factor for recurrence by multiple regression analysis. CONCLUSIONS: These data suggest that there is no evidence for the existence of a separate, early recurring, aggressive disease type. Shorter reoperation-free survival after strictureplasty may reflect patterns of recurrence in ileal disease.

Adolescent↗