Zelen’s design

a type of randomized clinical trial in which patients are assigned to experimental conditions before they have consented to participate in the research. There are two versions of the design, both of which remain ethically controversial: In the single-consent strategy, patients assigned to the experimental treatment are told there is an alternative (the control) available and offered the option to switch; those in the control group are not informed of their study participation. In the double-consent strategy, both the experimental and control groups are offered the option to switch from the treatment to which they initially were assigned. [Marvin Zelen (1927– ), U.S. biostatistician]

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Psychology term of the day

July 27th 2024

object constancy

1. in object relations theory, the ability of an infant to maintain an attachment that is relatively independent of gratification or frustration, based on a cognitive capacity to conceive of a mother who exists when she is out of sight and who has positive attributes when she is unsatisfying. Thus, an infant becomes attached to the mother herself rather than to her tension-reducing ministrations; she comes to exist continuously for the infant and not only during instances of need satisfaction. This investment by an infant in a specific libidinal object indicates that he or she no longer finds people to be interchangeable.

2. see perceptual constancy.