PSYC 203 - Quasi-Experimental Designs & Applied Research

Chapter 11

design problems in applied research

* ethical problems (study outside of the lab may produce challenges for consent and privacy, debriefing may not be possible)
* trade-off between internal and external validity (field = less methodological control = lower internal validity; field = real life = higher external validity)
* impossible to use random assignment to form random groups (reduces internal validity)

quasi-experimental design

design which occurs when subjects cannot be assigned randomly

benefits of QED

* degree of control
* serve a researchers goals when ethical or practical problems make random assignment impossible
* often produce results with clear benefits for people's lives

designs that may be considered QED

* single-factor ex post facto designs with two or more levels
* ex post facto factorial designs
* P x E factorial designs
* all of the correlational research

2 types of QED

* nonequivalent control groups designs
* interrupted time series designs

nonequivalent control groups designs

a between-subjects design in which participants have not been randomly assigned to conditions

groups differ and are not equivalent at the outset of the study and they experience different events in the study

interrupted time series designs

when a researcher is able to take measures for an extended period of time before and after an event expected to influence behavior which allows for the evaluation of trends

interrupted time series with switching replications 

when a program can be implemented in different locations at different times

same treatment/program is put into place in two locations at two points in time  

program evaluation

procedures for determining if a need exists for a program and who would benefit if the program was implemented and how/if programs are being run accoding to plan

components of program evaluation

* planning for programs; needs analysis
* monitoring programs; formative evaluation
* evaluating outcomes; summative evaluation
* weighing costs; cost-effectiveness

cost-effectiveness analysis

component of weighing the costs within program evaluation

monitoring the actual costs of a program and relating those costs the effectiveness of the program's outcomes

summative evaluations

component of evaluating outcomes within program evaluation

overall assessments of program effectiveness

formative evaluations

component of monitoring programs within program evaluation

form of program evaluation that monitors the functioning of a program while it is operating to determine if it is functioning as planned

needs analysis

component of planning for programs within program evaluation

a set of procedures for predicting whether a population of sufficient size exists that would benefit from the proposed program, whether the program could solve a clearly defined problem, and whether members of the population would actually use the program  

ways to identify need for a needs analysis

* census data
* surveys of available resources
* surveys of potential users
* key informants/focus groups/community forums 

key informants

way to identify need for a needs analysis

someone about the community that has a great deal of knowledge and specialized knowledge about the problem at hand that is otherwise unavailable to the researcher  

focus group

way to identify need for a needs analysis

a small group whose members respond to a set of open-ended questions about some topic 

community forum

way to identify need for a needs analysis

open meeting at which all members of a community affected by a potential program are invited to come and participate