Observer bias

Biased treatment outcome assessment can result if people receiving or providing care, or others assessing treatment outcomes, know which participants have received which treatments. It is sometimes possible to conceal which treatments have been received by using placebos and in other ways.  See also Double Dummy.


JLL Essay
2.4 The need to avoid differences in the way treatment outcomes are assessed

Following up everyone in treatment comparisons

 

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Scadding JG (2002).
Reflections on my studies of the effects of sulphonamide drugs in bacillary dysentery in Egypt, 1943-1944. JLL Bulletin: Commentaries on the history of treatment evaluation.

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Senn SJ (2003).
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Tröhler U (2003).
Adolf Bingel (1879-1953). JLL Bulletin: Commentaries on the history of treatment evaluation.

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Clarke M (2004).
The 1944 patulin trial of the British Medical Research Council: an example of how concerted common purpose can get reliable answers to important questions very quickly. JLL Bulletin: Commentaries on the history of treatment evaluation.

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Kaptchuk TJ (2004).
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Spanager L (2005).
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Inventing the randomized double-blind trial: The Nürnberg salt test of 1835. JLL Bulletin: Commentaries on the history of treatment evaluation.

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Tröhler U (2010).
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Marušić A, Fatović-Ferenčić S (2012).
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Toth B (2015).
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Donaldson IML (2016).
Antoine de Lavoisier’s role in designing a single-blind trial to assess whether ‘Animal Magnetism’ exists. JLL Bulletin: Commentaries on the history of treatment evaluation.

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Zwarenstein M (2016).
‘Pragmatic’ and ‘Explanatory’ attitudes to randomized trials. JLL Bulletin: Commentaries on the history of treatment evaluation.

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2.4 The need to avoid differences in the way treatment outcomes are assessed

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الاختلافات بين الطريقة التي يجري بها تقيـيم المعالجات

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