Oldal 96 [96]
ZSUZSANNA MIRNICS
community members. Ihese may include data on work performance, work
absence, fluctuation statistics etc. Community data or other objective data
may be taken as well, about a client’s economic contribution to his or her
community."
To be useful in an effectiveness analysis, measures of supervision outcome
must be both reliable and valid. Reliability means that the measure gives
the same finding over multiple uses (assuming no change in what is being
measured) and provides the same findings when used by different researchers.
Validity means that the measure assesses the outcomes that it is supposed
to measure and provides data that are generalizable. Neither reliability nor
validity is intended as a theoretical concept; each is established by pre-testing
the measuring instrument".
Experimental designs are also highly recommended. The classical type
assigns clients either to receive intervention or not to receive it, according to
a random selection procedure. The functioning of each subject is measured
following the process. Client functioning under the control condition is used
to “subtract” the “effects” due to intervention from the “effects” due to other
factors. When this type of supervision versus no-supervision research de¬
sign is used, explanations of apparent improvements by factors other than
supervision itself can be rejected with reasonable confidence. As long as clients
have been assigned randomly to the different conditions, it can be assumed
(within identifiable probability limits) that the obtained “effects” are due to the
intervention. Control groups are necessary; otherwise such inferences about
causal factors are extremely difficult to develop. A multiple group (supervision
vs. supervision) design is slightly different: here, superiority of one intervention
or method over another can be tested. In such comparison studies clients are
assigned randomly to method A, method B etc.!?
Another suggested approach is use so-called mediator variables in statistical
analyses. Mediators show important relations between an intervention and
outcome, but may not explain the precise process of change." Establishing a
mediator has several reguirements. First, I would not want multiple mediators
10 Ibid.; Office of Technology Assessment, Washington D.C., Congress of the United States. Seri¬
es of papers on technology assessment, Background paper 3, The Efficacy and Cost Effectiveness
of Psychotherapy, October 1980, www.princeton.edu/~ota/disk3/1980/8020/802005.PDF,
accessed 1 September 2015.
See for instance: J. C. Nunnally — H. Bernstein, Psychometric theory, 3rd ed., New York,
McGraw-Hill, 1994.
Office of Technology Assessment, The Efficacy and Cost Effectiveness of Psychotherapy.
A.E. Kazdin, Mediators and mechanisms of change in psychotherapy research, Annual Review
of Clinical Psychology 3 (2007) 1-27.
+ 94 +