S W Duffy

Biographic Data

ID6160523
NAMES W Duffy
GIVEN NAMESS W
FAMILY NAMEDuffy
SIGNATUREDUFFY S W
AFFILIATIONSUniversity of Edinburgh
ORCID0000-0001-8793-943X
VERIFIEDYes
TOTAL WORKS8
TOTAL CITATIONS16
WORKS AS AUTHOR8
WORKS AS EDITOR0
FIRST PUBLICATION YEAR1983
LATEST PUBLICATION YEAR2004
H-INDEX2

  • A simple model for potential use with a misclassified binary outcome in epidemiology

    Stephen Duffy, S W Duffy et al.ARTICLEJournal of Epidemiology and…2004References: 13

    Study objective: Error in determination of disease outcome occurs in epidemiology, but such error is not usually corrected for in statistical analysis. A method of correction of risk estimates for misclassification of a binary disease outcome is developed here. Methods: The method is a simple, closed form correction to the logistic regression estimate. A closed form variance estimate is also developed. Setting: The method is illustrated in two st…

  • Evaluation by Markov chain models of a non-randomised breast cancer screening programme in women aged under 50 years in Sweden

    Chien‐jen Chen, H H Chen et al.ARTICLEJournal of Epidemiology and…1998References: 14

    STUDY OBJECTIVE: To apply Markov chain models that have previously been used on data in randomised trials of breast cancer screening to data from an uncontrolled service screening programme; to compare results with those from a randomised trial. DESIGN: A service screening programme in Uppsala county, Sweden, inviting 25,660 women aged 39-49 to mammographic screening every 20 months, and the Swedish Two-County Trial inviting 19,844 women aged 40-…

  • External validation, repeat determination, and precision of risk estimation in misclassified exposure data in epidemiology

    Stephen Duffy, S W Duffy et al.ARTICLEJournal of Epidemiology and…1992Cited by: 1References: 8

    STUDY OBJECTIVE--The aim was to quantify the difference in precision of risk estimates in epidemiology between the situations where misclassification of exposure is corrected for by external validation and where it is corrected for by internal repeat measurement. Precision was measured in terms of the expected width of the 95% confidence interval on the odds ratio. DESIGN--In a hypothetical case-control study, first with 100 cases and 100 control…

  • Risk factors for cancer of the buccal and labial mucosa in Kerala, southern India

    Rengaswamy Sankaranarayanan, S W Duffy et al.ARTICLEJournal of Epidemiology and…1990References: 12

    STUDY OBJECTIVE--The aim was to investigate risk factors for cancer of the buccal and labial mucosa in Kerala, southern India. DESIGN--The investigation was a case-control study. SETTING--Regional Cancer Centre, Trivandrum, Kerala, and local teaching hospitals. PARTICIPANTS--Cases were all those registered with oral cancers at the Regional Cancer Centre during 1983 and 1984 (n = 414). Controls (n = 895) were selected from admissions to the cancer…

  • The Swedish two county trial of mammographic screening for breast cancer

    Làszló Tabár, G Fagerberg et al.ARTICLEJournal of Epidemiology and…1989Cited by: 12References: 7

    The Swedish two county trial of breast cancer screening is now in its tenth year. This paper presents detailed results on mortality from breast cancer and from all other causes, and on the population denominators at risk for each of the first 8 years of follow up, for each county separately. These data represent a two year update on the last major report. Results show an increasingly significant deficit in deaths from breast cancer among the 77,0…

  • Alcohol Consumption By Patients Attending Outpatient Clinics

    Open AccessG Potamianos, Dennis M Gorman et al.ARTICLEInternational Journal of Social…1988

    Three hundred and twenty nine (329) patients aged between 18 and 60 years atten ding the diabetic, hypertension and fracture clinics were studied with regard to their alcohol consumption. The findings confirm the general view that a considerable number of patients atten ding the general medical services may be considered as problem drinkers, a factor which may contribute to their overall medical complaint

  • Risk factors for breast cancer

    S W Duffy, M M Roberts et al.ARTICLEJournal of Epidemiology and…1983Cited by: 3References: 8

    In a study of risk factors for breast cancer in women aged between 40 and 60 information was obtained from 236 cases identified at a diagnostic clinic and 2962 controls with no breast abnormality who attended a screening clinic. Statistical analysis of the data used information on a further 167 women who had attended both clinics to correct for possible between clinic bias in questionnaire responses. Relative risk was estimated in four 5 year age…

  • Risk factors relevant to cystic breast disease

    S W Duffy, M M Roberts et al.ARTICLEJournal of Epidemiology and…1983References: 14

    A total of 188 women aged 40-54 with cystic breast disease and 2213 asymptomatic controls were questioned in Edinburgh between 1974 and 1978 concerning marital, reproductive, and menstrual status, history of oral contraception use, history of previous breast complaints, and a family history of breast cancer. Women with a history of breast biopsy were at an increased risk of the disease and those past the menopause were at a decreased risk. These …