Displaying publications 61 - 80 of 101 in total

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  1. Bonsu KO, Reidpath DD, Kadirvelu A
    Cardiovasc Ther, 2015 Dec;33(6):338-46.
    PMID: 26280110 DOI: 10.1111/1755-5922.12150
    Statins are known to prevent heart failure (HF). However, it is unclear whether statins as class or type (lipophilic or hydrophilic) improve outcomes of established HF.
  2. Naftalin CM, Wong NS, Chan DP, Wong KH, Reidpath DD, Lee SS
    Int J STD AIDS, 2015 Oct;26(11):803-9.
    PMID: 25281539 DOI: 10.1177/0956462414553826
    To explore the heterogeneity of CD4 responses following highly active antiretroviral therapy, the patterns of CD4 recovery of HIV-1-infected Chinese patients who have been on their first antiretroviral regimen for ≥5 years were analysed. The CD4 trajectories were traced, smoothed and differentiated into three defined profiles. Half (56.3%) were 'satisfactory responders', with CD4 gain of >100 cells/μL and a peak of >350 cells/μL, plateauing before the end of Year 5. Thirty-three (24.4%) were 'continuing responders' whose CD4 rise persisted at Year 4-5. The remaining 26 (19.3%) were 'poor responders'. Presentation with AIDS before therapy was common not just among 'poor' but also paradoxically the 'continuing' responders. While a majority had responded well to antiretroviral therapy, older patients and those with AIDS diagnosis before initiation of therapy may never achieve a satisfactory level even with effective treatment. Categorization of HIV patients by their CD4 trajectory may support the prediction of immunological outcome over time, and ultimately inform treatment choices.
  3. Aborigo RA, Allotey P, Reidpath DD
    Soc Sci Med, 2015 May;133:59-66.
    PMID: 25841096 DOI: 10.1016/j.socscimed.2015.03.046
    Traditional medical systems in low income countries remain the first line service of choice, particularly for rural communities. Although the role of traditional birth attendants (TBAs) is recognised in many primary health care systems in low income countries, other types of traditional practitioners have had less traction. We explored the role played by traditional healers in northern Ghana in managing pregnancy-related complications and examined their relevance to current initiatives to reduce maternal morbidity and mortality. A grounded theory qualitative approach was employed. Twenty focus group discussions were conducted with TBAs and 19 in-depth interviews with traditional healers with expertise in managing obstetric complications. Traditional healers are extensively consulted to manage obstetric complications within their communities. Their clientele includes families who for either reasons of access or traditional beliefs, will not use modern health care providers, or those who shop across multiple health systems. The traditional practitioners claim expertise in a range of complications that are related to witchcraft and other culturally defined syndromes; conditions for which modern health care providers are believed to lack expertise. Most healers expressed a willingness to work with the formal health services because they had unique knowledge, skills and the trust of the community. However this would require a stronger acknowledgement and integration within safe motherhood programs.
  4. Allotey PA, Reidpath DD, Evans NC, Devarajan N, Rajagobal K, Bachok R, et al.
    Glob Health Action, 2015 Jan;8(1):28219.
    PMID: 28156759 DOI: 10.3402/gha.v8.28219
    Background Verbal autopsies have gained considerable ground as an acceptable alternative to medically determined cause of death. Unlike with clinical or more administrative settings for data collection, verbal autopsies require significant involvement of families and communities, which introduces important social and cultural considerations. However, there is very little clear guidance about the methodological issues in data collection. The objectives of this case study were: to explore the range of bereavement rituals within the multi-ethnic, multi-faith population of the district; to investigate the preparedness of communities to talk about death; to describe the verbal autopsy process; to assess the effects of collecting verbal autopsy data on data collectors; and to determine the most accurate sources of information about deaths in the community. Methods A case study approach was used, using focus group discussions, indepth interviews and field notes. Thematic analyses were undertaken using NVivo. Results Consideration of cultural bereavement practices is importance to acceptance and response rates to verbal autopsies. They are also important to the timing of verbal autopsy interviews. Well trained data collectors, regardless of health qualifications are able to collect good quality data, but debriefing is important to their health and well being. This article contributes to guidance on the data collection procedures for verbal autopsies within community settings.
  5. Allotey P, Reidpath DD, Devarajan N, Rajagobal K, Yasin S, Arunachalam D, et al.
    Glob Health Action, 2014 Dec;7(1):23176.
    PMID: 28672450 DOI: 10.3402/gha.v7.23176
    Background Community engagement is an increasingly important requirement of public health research and plays an important role in the informed consent and recruitment process. However, there is very little guidance about how it should be done, the indicators for assessing effectiveness of the community engagement process and the impact it has on recruitment, retention, and ultimately on the quality of the data collected as part of longitudinal cohort studies. Methods An instrumental case study approach, with data from field notes, policy documents, unstructured interviews, and focus group discussions with key community stakeholders and informants, was used to explore systematically the implementation and outcomes of the community engagement strategy for recruitment of an entire community into a demographic and health surveillance site in Malaysia. Results For a dynamic cohort, community engagement needs to be an ongoing process. The community engagement process has likely helped to facilitate the current response rate of 85% in the research communities. The case study highlights the importance of systematic documentation of the community engagement process to ensure an understanding of the effects of the research on recruitment and the community. Conclusions A critical lesson from the case study data is the importance of relationships in the recruitment process for large population-based studies, and the need for ongoing documentation and analysis of the impact of cumulative interactions between research and community engagement.
  6. Komahan K, Reidpath DD
    Am J Epidemiol, 2014 Aug 1;180(3):325-9.
    PMID: 24944286 DOI: 10.1093/aje/kwu129
    Correct identification of ethnicity is central to many epidemiologic analyses. Unfortunately, ethnicity data are often missing. Successful classification typically relies on large databases (n > 500,000 names) of known name-ethnicity associations. We propose an alternative naïve Bayesian strategy that uses substrings of full names. Name and ethnicity data for Malays, Indians, and Chinese were provided by a health and demographic surveillance site operating in Malaysia from 2011-2013. The data comprised a training data set (n = 10,104) and a test data set (n = 9,992). Names were spliced into contiguous 3-letter substrings, and these were used as the basis for the Bayesian analysis. Performance was evaluated on both data sets using Cohen's κ and measures of sensitivity and specificity. There was little difference between the classification performance in the training and test data (κ = 0.93 and 0.94, respectively). For the test data, the sensitivity values for the Malay, Indian, and Chinese names were 0.997, 0.855, and 0.932, respectively, and the specificity values were 0.907, 0.998, and 0.997, respectively. A naïve Bayesian strategy for the classification of ethnicity is promising. It performs at least as well as more sophisticated approaches. The possible application to smaller data sets is particularly appealing. Further research examining other substring lengths and other ethnic groups is warranted.
  7. Masood M, Masood Y, Reidpath DD, Newton T
    Lancet, 2014 Jun 14;383(9934):2046.
    PMID: 24931691 DOI: 10.1016/S0140-6736(14)60996-X
  8. Reidpath DD, Masood M, Allotey P
    Int J Public Health, 2014 Jun;59(3):503-7.
    PMID: 24045784 DOI: 10.1007/s00038-013-0510-1
    OBJECTIVES: Four metrics to characterise population overweight are described.

    METHODS: Behavioural Risk Factors Surveillance System data were used to estimate the weight the US population needed to lose to achieve a BMI 

  9. Masood M, Reidpath DD
    Curr Med Res Opin, 2014 May;30(5):857-63.
    PMID: 24328497 DOI: 10.1185/03007995.2013.875466
    BACKGROUND: The aim of this paper was to review the types of approaches currently utilized in the analysis of multi-country survey data, specifically focusing on design and modeling issues with a focus on analyses of significant multi-country surveys published in 2010.
    METHODS: A systematic search strategy was used to identify the 10 multi-country surveys and the articles published from them in 2010. The surveys were selected to reflect diverse topics and foci; and provide an insight into analytic approaches across research themes. The search identified 159 articles appropriate for full text review and data extraction.
    RESULTS: The analyses adopted in the multi-country surveys can be broadly classified as: univariate/bivariate analyses, and multivariate/multivariable analyses. Multivariate/multivariable analyses may be further divided into design- and model-based analyses. Of the 159 articles reviewed, 129 articles used model-based analysis, 30 articles used design-based analyses. Similar patterns could be seen in all the individual surveys.
    CONCLUSION: While there is general agreement among survey statisticians that complex surveys are most appropriately analyzed using design-based analyses, most researchers continued to use the more common model-based approaches. Recent developments in design-based multi-level analysis may be one approach to include all the survey design characteristics. This is a relatively new area, however, and there remains statistical, as well as applied analytic research required. An important limitation of this study relates to the selection of the surveys used and the choice of year for the analysis, i.e., year 2010 only. There is, however, no strong reason to believe that analytic strategies have changed radically in the past few years, and 2010 provides a credible snapshot of current practice.
  10. Reidpath DD, Davey TM, Kadirvelu A, Soyiri IN, Allotey P
    Prev Med, 2014 Feb;59:37-41.
    PMID: 24270054 DOI: 10.1016/j.ypmed.2013.11.011
    OBJECTIVES: Evidence that age of smoking initiation represents a risk factor for regular smoking in adolescence is complicated by inconsistencies in the operational definition of smoking initiation and simultaneous inclusion of age as an explanatory variable. The aim of this study was to examine the relationship between age, age of smoking initiation and subsequent regular smoking.
    METHODS: A secondary analysis was conducted of the U.S. Youth Risk Behavior Survey 2011. A sex stratified multivariable logistic regression analysis was used to model the likelihood of regular smoking with age and age of smoking initiation as explanatory variables and race/ethnicity as a covariate.
    RESULTS: After controlling for race/ethnicity, age and age of smoking initiation were independently associated with regular smoking in males and females. Independent of age, a one year's decrease in the age of smoking initiation was associated with a 1.27 times increase in odds of regular smoking in females (95% CI: 1.192-1.348); and similar associations for males (OR: 1.28; 95% CI: 1.216-1.341).
    CONCLUSION: While the majority of high school students do not become regular smokers after initiating smoking, earlier initiation of smoking is associated with subsequent regular smoking irrespective of sex or race/ethnicity. These findings have potentially important implications for intervention targeting.
    KEYWORDS: Adolescent; Epidemiology; Smoking
  11. Jahan N, Allotey P, Arunachalam D, Yasin S, Soyiri IN, Davey TM, et al.
    BMC Public Health, 2014;14 Suppl 2:S8.
    PMID: 25081203 DOI: 10.1186/1471-2458-14-S2-S8
    Health services can only be responsive if they are designed to service the needs of the population at hand. In many low and middle income countries, the rate of urbanisation can leave the profile of the rural population quite different from the urban population. As a consequence, the kinds of services required for an urban population may be quite different from that required for a rural population. This is examined using data from the South East Asia Community Observatory in rural Malaysia and contrasting it with the national Malaysia population profile.
  12. Reidpath DD, Ahmadi K
    PMID: 25126103 DOI: 10.1186/1742-7622-11-9
    BACKGROUND: Measures of household socio-economic position (SEP) are widely used in health research. There exist a number of approaches to their measurement, with Principal Components Analysis (PCA) applied to a basket of household assets being one of the most common. PCA, however, carries a number of assumptions about the distribution of the data which may be untenable, and alternative, non-parametric, approaches may be preferred. Mokken scale analysis is a non-parametric, item response theory approach to scale development which appears never to have been applied to household asset data. A Mokken scale can be used to rank order items (measures of wealth) as well as households. Using data on household asset ownership from a national sample of 4,154 consenting households in the World Health Survey from Vietnam, 2003, we construct two measures of household SEP. Seventeen items asking about assets, and utility and infrastructure use were used. Mokken Scaling and PCA were applied to the data. A single item measure of total household expenditure is used as a point of contrast.

    RESULTS: An 11 item scale, out of the 17 items, was identified that conformed to the assumptions of a Mokken Scale. All the items in the scale were identified as strong items (Hi > .5). Two PCA measures of SEP were developed as a point of contrast. One PCA measure was developed using all 17 available asset items, the other used the reduced set of 11 items identified in the Mokken scale analaysis. The Mokken Scale measure of SEP and the 17 item PCA measure had a very high correlation (r = .98), and they both correlated moderately with total household expenditure: r = .59 and r = .57 respectively. In contrast the 11 item PCA measure correlated moderately with the Mokken scale (r = .68), and weakly with the total household expenditure (r = .18).

    CONCLUSION: The Mokken scale measure of household SEP performed at least as well as PCA, and outperformed the PCA measure developed with the 11 items used in the Mokken scale. Unlike PCA, Mokken scaling carries no assumptions about the underlying shape of the distribution of the data, and can be used simultaneous to order household SEP and items. The approach, however, has not been tested with data from other countries and remains an interesting, but under researched approach.

  13. Davey TM, Allotey P, Reidpath DD
    Public Health, 2013 Dec;127(12):1057-62.
    PMID: 24268545 DOI: 10.1016/j.puhe.2013.09.008
    Effective population-level solutions to the obesity pandemic have proved elusive. In low- and middle-income countries the problem may be further challenged by the perceived internal tension between economic development and sustainable solutions which create the optimal conditions for human health and well-being. This paper discusses some of the ecological obstacles to addressing the growing problem of obesity in 'aspiring' economies, using Malaysia as a case study. The authors conclude that current measures to stimulate economic growth in Malaysia may actually be exacerbating the problem of obesity in that country. Public health solutions which address the wider context in which obesity exists are needed to change the course of this burgeoning problem.
  14. Soyiri IN, Reidpath DD, Sarran C
    Int J Biometeorol, 2013 Jul;57(4):569-78.
    PMID: 22886344 DOI: 10.1007/s00484-012-0584-0
    Asthma is a chronic condition of great public health concern globally. The associated morbidity, mortality and healthcare utilisation place an enormous burden on healthcare infrastructure and services. This study demonstrates a multistage quantile regression approach to predicting excess demand for health care services in the form of asthma daily admissions in London, using retrospective data from the Hospital Episode Statistics, weather and air quality. Trivariate quantile regression models (QRM) of asthma daily admissions were fitted to a 14-day range of lags of environmental factors, accounting for seasonality in a hold-in sample of the data. Representative lags were pooled to form multivariate predictive models, selected through a systematic backward stepwise reduction approach. Models were cross-validated using a hold-out sample of the data, and their respective root mean square error measures, sensitivity, specificity and predictive values compared. Two of the predictive models were able to detect extreme number of daily asthma admissions at sensitivity levels of 76 % and 62 %, as well as specificities of 66 % and 76 %. Their positive predictive values were slightly higher for the hold-out sample (29 % and 28 %) than for the hold-in model development sample (16 % and 18 %). QRMs can be used in multistage to select suitable variables to forecast extreme asthma events. The associations between asthma and environmental factors, including temperature, ozone and carbon monoxide can be exploited in predicting future events using QRMs.
  15. Ahmadi K, Reidpath DD, Allotey P, Hassali MA
    BMJ Open, 2013 May 28;3(5).
    PMID: 23793653 DOI: 10.1136/bmjopen-2013-002755
    INTRODUCTION: HIV/AIDS-related stigma affects the access and utilisation of health services. Although HIV/AIDS-related stigma in the health services has been studied, little work has attended to the relationship between professional development and stigmatising attitudes. Hence, in this study, we will extend earlier research by examining the relationship between the stage of professional development and the kinds of stigmatising attitudes held about people living with HIV/AIDS.

    METHODS AND ANALYSIS: A serial cross-sectional design will be combined with a two-point in time longitudinal design to measure the levels of stigma among healthcare students from each year of undergraduate and graduate courses in Malaysia and Australia. In the absence of suitable measures, we will carry out a sequential mixed methods design to develop such a tool. The questionnaire data will be analysed using mixed effects linear models to manage the repeated measures.

    ETHICS AND DISSEMINATION: We have received ethical approval from the Monash MBBS executive committee as well as the Monash University Human Research Ethics Committee. We will keep the data in a locked filing cabinet in the Monash University (Sunway campus) premises for 5 years, after which the information will be shredded and disposed of in secure bins, and digital recordings will be erased in accordance with Monash University's regulations. Only the principal investigator and the researcher will have access to the filing cabinet. We aim to present and publish the results of this study in national and international conferences and peer-reviewed journals, respectively.

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