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T A Blakely

Publications and source records attributed to T A Blakely.

11 recordsLinked to original sources
PubMed2001

Socioeconomic inequality in voting participation and self-rated health.

OBJECTIVES: This study tested the hypothesis that disparities in political participation across socioeconomic status affect health. Specifically, the association of voting inequality at the state level with individual self-rated health was examined. METHODS: A multilevel study of 279,066 respondents to the Current Population Survey (CPS) was conducted. State-level inequality in voting turnout by socioeconomic status (family income and educational attainment) was derived from November CPS data for 1990, 1992, 1994, and 1996. RESULTS: Individuals living in the states with the highest voting inequality had an odds ratio of fair/poor self-rated health of 1.43 (95% confidence interval [CI] = 1.22, 1.68) compared with individuals living in the states with the lowest voting inequality. This odds ratio decreased to 1.34 (95% CI = 1.14, 1.56) when state income inequality was added and to 1.27 (95% CI = 1.10, 1.45) when state median income was included. The deleterious effect of low individual household income on self-rated health was most pronounced among states with the greatest voting and income inequality. CONCLUSIONS: Socioeconomic inequality in political participation (as measured by voter turnout) is associated with poor self-rated health, independently of both income inequality and state median household income.

Adult↗
PubMed2000

Ecological effects in multi-level studies.

Multi-level research that attempts to describe ecological effects in themselves (for example, the effect on individual health from living in deprived communities), while also including individual level effects (for example, the effect of personal socioeconomic disadvantage), is now prominent in research on the socioeconomic determinants of health and disease. Such research often involves the application of advanced statistical multi-level methods. It is hypothesised that such research is at risk of reaching beyond an epidemiological understanding of what constitutes an ecological effect, and what sources of error may be influencing any observed ecological effect. This paper aims to present such an epidemiological understanding. Three basic types of ecological effect are described: a direct cross level effect (for example, living in a deprived community directly affects individual personal health), cross level effect modification (for example, living in a deprived community modifies the effect of individual socioeconomic status on individual health), and an indirect cross level effect (for example, living in a deprived community increases the risk of smoking, which in turn affects individual health). Sources of error and weaknesses in study design that may affect estimates of ecological effects include: a lack of variation in the ecological exposure (and health outcome) in the available data; not allowing for intraclass correlation; selection bias; confounding at both the ecological and individual level; misclassification of variables; misclassification of units of analysis and assignment of individuals to those units; model mis-specification; and multicollinearity. Identification of ecological effects requires the minimisation of these sources of error, and a study design that captures sufficient variation in the ecological exposure of interest.

Bias↗
PubMed1999

The 1996 pertussis epidemic in New Zealand: vaccine effectiveness.

AIM: To assess if reduced vaccine effectiveness may have accounted for increased hospitalisations in the 1996 pertussis epidemic. METHODS: Vaccine effectiveness was estimated by comparing vaccine coverage of the population (derived from a literature review) with that of cases (from notification data available from 1 June 1996) -- the screening method. Only three doses of pertussis vaccine were in the immunisation schedule until 1996, so vaccine effectiveness was calculated for three or more doses. RESULTS: Most likely estimates of vaccine effectiveness for Europeans were 88% (95% confidence interval 71 to 95%) for 5- to 14-month-olds, 80% for 15-month to 4-year-olds (66 to 88%) but lower for children aged 5 years and older with confidence limits including zero. Vaccine effectiveness estimates for Maori were less for each age group but based on few observations. CONCLUSIONS: The increase in hospitalisations for young children in the 1996 epidemic cannot be directly attributed to a reduced vaccine effectiveness, as vaccine effectiveness estimates for preschool Europeans are in line with international evidence. Additionally, the vaccine effectiveness estimates in this study are likely to be underestimates due to bias. The lower estimates for vaccine effectiveness among Maori are likely to reflect increased pressure of these biases, although a biological basis for the difference or clustering of factors that cause failure are also possible. The vaccine effectiveness estimates decrease with age, a likely combination of waning vaccine immunity and the cross-sectional nature of the screening method itself for determining vaccine effectiveness.

Child↗
PubMed1999

Hepatitis B carriage explains the excess rate of hepatocellular carcinoma for Maori, Pacific Island and Asian people compared to Europeans in New Zealand.

BACKGROUND: The aim of this research was to determine the hepatitis B surface antigen (HBsAg) carrier prevalence among cases of hepatocellular carcinoma (HCC), and the population attributable risk of HBsAg carriage for HCC, by ethnicity in New Zealand. METHODS: The hospital notes of HCC cases registered with the New Zealand Cancer Registry, for the years 1987-1994 inclusive, were viewed to determine the HBsAg status. Results The HBsAg status was determined for 193 cases of HCC. The HBsAg carrier prevalence for non-Europeans with HCC was markedly higher than that for Europeans, being 76.7% for Maori, 80.0% for Pacific Island people, and 88.5% for Asians, compared to 6.0% for Europeans. In addition to the effect of ethnicity, HCC cases aged <60 years were more likely to be HBsAg carriers than those aged > or = 60 years. The estimated population attributable risk of HBsAg for HCC, within each ethnic group, was only marginally less than the HBsAg prevalence due to the high relative risk of HBsAg carriage for HCC. The standardized incidence rate ratios of HCC for Maori, Pacific Island people and Asians compared to Europeans were 9.6, 20.4, and 22.3, respectively. Hepatocellular carcinoma attributable to HBsAg carriage explained 79%, 83%, and 92% of the excess standardized rate of HCC, compared to Europeans, for Maori, Pacific Island people, and Asians, respectively. Conclusions The HBsAg carrier prevalence in non-European cases of HCC in New Zealand is between 75% and 90%. HBsAg carriage explains the majority of the excess rate of HCC in non-Europeans compared to Europeans in New Zealand.

Adolescent↗
PubMed1993

Mild head injury is not always mild; implications for damage litigation.

The traditional view that mild head injury involves an essentially reversible physiological process is examined and is found to be largely invalid. It is concluded that long-term impairment following mild head injury is fairly common and that the degree of impairment can be assessed clinically. Such an assessment involves a combination of objective electrophysiological and psychometric investigations as well as professional interpretation. With the use of this approach the possibility of malingering can be ruled out in most cases and significant impairment, when it exists, can be demonstrated beyond reasonable doubt.

Adult↗
PubMed1991

Orientation in time: implications for psychopathology and psychotherapy.

Considerations derived from the fields of physics, philosophy, anthropology, and psychology suggest that our popular conception of time as a unidirectional and uniform flow may not be an adequate description of the human experience of time. Indeed, other dimensions of temporality may constitute important aspects of human phenomenology with respect to both adaptive and maladaptive or psychopathological mental states. Exploration of the temporal aspect of experience and temporal reorientation may be helpful psychotherapeutic maneuvers that are greatly facilitated by hypnosis.

Adolescent↗