Research participation effects: a skeleton in the methodological cupboard.
OBJECTIVE
There have been concerns about impacts of various aspects of taking part in research studies for a century. The concerns have not, however, been sufficiently well conceptualized to form traditions of study capable of defining and elaborating the nature of these problems. In this article we present a new way of thinking about a set of issues attracting long-standing attention.


METHODS
We briefly review existing concepts and empirical work on well-known biases in surveys and cohort studies and propose that they are connected.


RESULTS
We offer the construct of "research participation effects" (RPE) as a vehicle for advancing multi-disciplinary understanding of biases. Empirical studies are needed to identify conditions in which RPE may be sufficiently large to warrant modifications of study design, analytic methods, or interpretation. We consider the value of adopting a more participant-centred view of the research process as a way of thinking about these issues, which may also have benefits in relation to research methodology more broadly.


CONCLUSIONS
Researchers may too readily overlook the extent to which research studies are unusual contexts, and that people may react in unexpected ways to what we invite them to do, introducing a range of biases.
Faculty of Public Health & Policy, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK. Electronic address: Jim.McCambridge@lshtm.ac.uk.
Jim
J
McCambridge
Centre for Clinical Epidemiology and Biostatistics, School of Medicine and Public Health, University of Newcastle, HMRI Building, Callaghan NSW 2308, Australia.
Kypros
K
Kypri
Department of Medical Statistics, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
Diana
D
Elbourne
D015982:Bias; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000379:methods* / Q000523:psychology* / Q000592:standards; D012107:Research Design / Q000592:standards*; D035842:Research Subjects / Q000523:psychology*
Bias; Cohort studies; Hawthorne effect; Mixed methods; Research assessment; Research methods; Research participation; Surveys