Quantifying the potential role of unmeasured confounders: The example of influenza vaccination

International Journal of Epidemiology

Volumn 37, Issue 6, 2008, Pages 1422-1429

  Groenwold, R H H ^a   Hoes, Aw ^a   Nichol, K L ^b   Hak, E ^a  

^a UNIVERSITY MEDICAL CENTER UTRECHT   (Netherlands)

^b VETERANS AFFAIRS MEDICAL CENTER   (United States)

Author keywords

Bias; Confounding; Influenza vaccines

Indexed keywords

ANTIDIABETIC AGENT; CARDIOVASCULAR AGENT; HYDROXYMETHYLGLUTARYL COENZYME A REDUCTASE INHIBITOR; INFLUENZA VACCINE; RESPIRATORY TRACT AGENT;

ASSESSMENT METHOD; COVARIANCE ANALYSIS; HEALTH CARE; HEALTH STATUS; INFLUENZA; MULTIVARIATE ANALYSIS; QUESTIONNAIRE SURVEY; REGRESSION ANALYSIS; SOCIOECONOMIC STATUS; VACCINATION;

AGED; ALCOHOL CONSUMPTION; ARTICLE; COMMUNITY LIVING; COMORBIDITY; CONFOUNDING VARIABLE; CONTROLLED STUDY; DATA BASE; FUNCTIONAL STATUS; HUMAN; INFLUENZA VACCINATION; MAJOR CLINICAL STUDY; MALE; MORTALITY; MULTIVARIATE LOGISTIC REGRESSION ANALYSIS; NETHERLANDS; PREDICTION; PRIORITY JOURNAL; QUANTITATIVE ANALYSIS; QUESTIONNAIRE; RANDOM SAMPLE; SMOKING;

AGED; CONFOUNDING FACTORS (EPIDEMIOLOGY); DATABASES, FACTUAL; FEMALE; HEALTH STATUS; HUMANS; INFLUENZA VACCINES; INFLUENZA, HUMAN; LOGISTIC MODELS; MALE; RISK FACTORS; SENSITIVITY AND SPECIFICITY; TREATMENT OUTCOME;

BENELUX; EURASIA; EUROPE; NETHERLANDS; UTRECHT; WESTERN EUROPE;

EID: 57349146580     PISSN: 03005771     EISSN: 14643685     Source Type: Journal    
DOI: 10.1093/ije/dyn173     Document Type: Article

References (21)

1. Miettinen OS, Cook EF. Confounding: Essence and detection. Am J Epidemiol 1981;114:593-603.
2. Nichol KL, Nordin JD, Nelson DB, Mullooly JP, Hak E. Effectiveness of influenza vaccination in the community-dwelling elderly. N Engl J Med 2007;357:1373-81.
3. Salas M, Hofman A, Stricker BH. Confounding by indication: An example of variation in the use of epidemiologic terminology. Am J Epidemiol 1999; 149:981-83.
4. Hak E, Verheij ThJM, Grobbee DE, Nichol KL, Hoes AW. Confounding by indication in non-experimental evaluation of vaccine effectiveness: The example of prevention of influenza complications. J Epidemiol Community Health 2002;56:951-55.
5. Hak E, Hoes AW, Nordin J, Nichol KL. Benefits of influenza vaccine in US elderly-appreciating issues of confounding bias and precision. Int J Epidemiol 2006; 35:800-02.
6. Toh S, Hernandez-Diaz S. Statins and fracture risk. A systematic review. Pharmacoepidemiol Drug Saf 2007; 16:627-40.
7. Klungel OH, Martens EP, Psaty BM et al. Methods to assess intended effects of drug treatment in observational studies are reviewed. J Clin Epidemiol 2004; 57:1223-31.
8. Stram DO, Huberman M, Wu AH. Is residual confounding a reasonable explanation for the apparent protective effects of beta-carotene found in epidemiologic studies of lung cancer in smokers? Am J Epidemiol 2002; 155:622-28.
9. Vandenbroucke JP. When are observational studies as credible as randomised trials? Lancet 2004;363:1728-31.
10. Hak E, Buskens E, van Essen GA et al. Clinical effectiveness of influenza vaccination in persons younger than 65 years with high-risk medical conditions: The PRISMA study. Arch Intern Med 2005;165 274-80.
11. Hak E, Wei F, Nordin J, Mullooly J, Poblete S, Nichol KL. Development and validation of a clinical prediction rule for hospitalization due to pneumonia or influenza or death during influenza epidemics among community-dwelling elderly persons. J Infect Dis 2004;189 450-58.
12. Jackson LA, Nelson JC, Benson P et al. Functional status is a confounder of the association of influenza vaccine and risk of all cause mortality in seniors. Int J Epidemiol 2006;35:345-52.
13. Hak E, van Loon S, Buskens E et al. Design of the Dutch prevention of influenza, surveillance and management (PRISMA) study. Vaccine 2003;21:1719-24.
14. Ware JE Jr, Sherbourne CD. The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection. Med Care 1992;30:473-83.
15. Kempen GI. [Assessment of health status of the elderly. Application of a Dutch version of the MOS scale]. Tijdschr Gerontol Geriatr 1992; 23:132-40.
16. Franks P, Gold MR, Fiscella K. Sociodemographics, self-related health, and mortality in the US. Soc Sci Med 2003;56:2505-14.
17. Crawford SL, Tennstedt SL, McKinlay JB. A omparison of analytic methods for non-random missingness of outcome data. J Clin Epidemiol 1995;48:209-19.
18. Greenland S, Finkle WD. A critical look at methods handling missing covariates in epidemiologic regression analyses. Am J Epidemiol 1995;142:1255-64.
19. van Buuren S, Oudshoorn C. Available at: http://web.inter.nl.net/users/ S.van.Buuren/mi/hmtl/mice.htm (Accessed on October 30, 2007).
20. Clark TG, Altman DG. Developing a prognostic model n the presence of missing data: An ovarian cancer case study. J Clin Epidemiol 2003;56:28-37.
21. Simonsen L. Taylor RJ, Viboud C, Miller MA, Jackson LA. Mortality benefits of influenza vaccination in elderly people: An ongoing controversy. Lancet Infect Dis 2007;7:658-66.